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于2026年10月14日向美国证券交易委员会提交

证券法文件编号 333-191151
\n投资公司法文件编号 811-22887

美国

证券交易委员会

华盛顿特区 20549

N-1A 表格

注册声明

\n \n \n \n \n \n \n \n \n \n \n \n \n

	*根据1933年证券法*	☐
	生效前修正案编号	☐
	生效后\n 修正案编号 93	☒

和/或

注册声明

\n \n \n \n \n

根据1940年投资公司法

☐

\n \n \n \n \n

修正案\n 编号 95

☒

(勾选适当的框)

Calamos ETF Trust

(注册人根据章程指定的全名)

2020 Calamos Court
\nNaperville, Illinois
\n(主要执行办公室地址)

60563
\n(邮政编码)

注册人的电话号码，包括区号：(630) 245-7200

Erik D. Ojala

2020 Calamos Court

Naperville, Illinois 60563

(服务代理人姓名和地址)

副本送达：

Paulita A. Pike 和 Rita Rubin
\nRopes & Gray LLP
\n191 North Wacker Drive, 32nd Floor
\nChicago, Illinois 60606

拟议公开发行的近似日期：

一旦注册声明生效，尽快进行。

拟议本文件将在以下时间生效：

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

	☒	在提交时立即生效\n 根据第(b)款
	☐	在，__________生效\n 根据第(b)款
	☐	提交后60天生效，根据第(a)(1)款
	☐	在[ ]生效，根据第(a)(1)款
	☐	提交后75天生效\n 根据第(a)(2)款
	☐	在[ ]生效，根据第(a)(2)款的规则 485。

如适用，请勾选以下框：

\n \n \n \n

☐	本生效后修正案为之前提交的生效后修正案指定了新的生效日期。

CALAMOS ETF TRUST

生效后修正案第93号的内容

本注册声明包括以下文件和资料：

封面表单

部分 A – Calamos 最小值自动回售收入ETF

部分 B – 附加信息声明

部分 C – 其他信息

签名页

附录索引

$\"\"$

\n\n

基金名称 \n	股票代码 \n	交易所 \n
Calamos 最小值自动回售收入ETF \n	CAYN \n	纽约证券交易所阿拉卡公司 \n

2026年10月14日的招募说明书

上述基金（“基金”）是Calamos ETF Trust（“信托”）的一个系列，也是一种交易所交易基金（“ETF”）。该基金在纽约证券交易所阿拉卡公司（“纽约证券交易所阿拉卡”或“交易所”）上市并主要交易其股份。

市场价格可能与股份的净资产值存在一定程度的差异。与共同基金不同，该基金仅以称为“创建单位”的大块股份为单位按净资产值发行和赎回。

除非以创建单位的形式聚合，否则股份不是该基金的可赎回证券。

美国证券交易委员会（“SEC”）和美国商品期货交易委员会（“CFTC”）并未批准或否决这些证券，也未对本招募说明书的真实性或充分性进行审查。与此相反的任何陈述都是犯罪行为。

\n\n\n\n\n\n\n\n\n\n\n\n\n\n

Calamos Least-Of Autocallable Income ETF	1
其他重要信息关于基金份额	15
关于投资策略及相关风险的更多信息	16
基金资料	33
	谁管理该基金？	33
	如何购买和出售份额	34
	股息、其他分配和税务	36
	净资产值	39
	基金服务提供商	40
	溢价/折价信息	40
	其他投资公司的投资	40
财务亮点	41
其他信息	42

Calamos Least-Of Autocallable Income ETF

投资目标

Calamos Least-Of Autocallable Income ETF (the “Fund”) seeks to generate high monthly income while providing reduced downside risk through exposure to the MerQube US Equity Least-Of Autocallable Index (the “Autocallable Index”). The Autocallable Index is designed to reflect the performance of a theoretical diversified portfolio of synthetic least-of autocallable notes (each an “Autocallable” and the theoretical portfolio of Autocallables, the “Index Portfolio”), the coupon, autocall and principal outcomes of which are determined by reference to the least-performing of a basket of three exchange-traded funds — the SPDR® S&P 500® ETF Trust (“SPY”), the Invesco QQQ TrustSM, Series 1 (“QQQ”) and the iShares® Russell 2000® ETF (“IWM”) (together, the “Underlying Reference Basket,” and each a “Constituent”). The reduced downside risk that the Fund seeks to deliver is relative to owning a single underlying least-of autocallable note (and not relative to the risk associated with investing in the Underlying Reference Basket or any Constituent), because exposure to the Autocallable Index is expected to provide benefits such as reduced timing risk, diversification across multiple Autocallable notes (i.e., not subject to a single maturity barrier), and contingent maturity barriers that may help preserve capital over time.

基金费用和开支

以下表格描述了您购买、持有和出售基金的份额（“基金份额”）时可能支付的费用。投资者可能支付其他费用，例如经纪佣金和其他向金融中介支付的费用，这些费用未反映在下面的表格和示例中。

\n\n\n\n\n\n\n\n\n

年度基金运营费用（您每年支付的费用，占您投资价值的百分比）：
管理费	0.74	%
分销和/或服务费用（12b-1）	0.00	%
其他费用1	0.00	%
收购基金费用和开支	0.12	%
年度总基金运营费用	0.86	%
费用减免和/或报销2	(0.12	)%
在减免和/或报销费用后的年度总基金运营费用	0.74	%

\n\n

1	“其他费用”是基于基金预计在本财年产生的费用的估算。

\n\n

2	Calamos Advisors LLC（“Calamos Advisors”或“Adviser”）已与基金签订合同，同意免除基金应向其支付的已购基金费用和开支，适用于基金投资的任何关联投资公司。该费用减免安排可在2029年12月1日或之后由Calamos Advisors LLC随时终止。

示例

本示例旨在帮助您比较投资该基金与其他基金的成本。该示例假设您在 indicated 的时间段内向该基金投资10,000美元，然后在这些时间段结束时卖出所有基金股份。该示例还假设您的投资每年有5%的回报，并且基金的运营费用保持不变。尽管您的实际成本可能更高或更低，但根据这些假设，无论您是卖出还是持有基金股份，您的成本将是：

\n\n

	第1年 \n		第3年 \n
	$76 \n		$237 \n

投资组合周转

该基金在购买和出售证券（或“周转”其投资组合）时会支付交易成本，如佣金。较高的投资组合周转率可能表明较高的交易成本，并且在基金股份持有于应税账户时可能导致更高的税款。这些成本未反映在年度基金运营费用或示例中，会影响基金的表现。由于该基金尚未开始运营，目前无法获得投资组合周转信息。

公开说明书 | 2026年10月14日

Calamos Least-Of Autocallable Income ETF

主要投资策略

该基金是一个非分散的、主动管理的交易所交易基金（“ETF”），在正常市场条件下，旨在将其总资产的至少80%投资于美国国债、现金、现金等价物、“箱式价差”（包括箱式价差ETF）和未认缴的总收益互换，以获得对MerQube美国股票Least-Of自动赎回指数（“自动赎回指数”）的敞口。该基金不会尝试复制或跟踪自动赎回指数，而是将使用总收益互换等金融工具来获得对自动赎回指数水平的敞口。该基金计划根据自动赎回指数的部分参考，每月向投资者分配金额。自动赎回指数旨在反映一个理论投资组合的综合表现，该投资组合包含大约52至156个合成Least-Of自动赎回票据，这些票据以阶梯结构排列，具有不同的进入点和类似的固定参数（“参数”），如下面“指数投资组合特征”部分所述。

自动赎回产品的票息支付、本金偿还时间和到期本金价值，以及最终基金的总回报，都是取决于条件的，并且就到期本金价值而言，取决于底层参考篮子（由SPY、QQQ或IWM组成）中表现最差的成分指数的表现。在每个观察日，表现最差的“成分”——即相对于该适用自动赎回产品被纳入指数投资组合时的水平，表现最差的成分——将决定该自动赎回产品的票息、自动赎回和本金结果。基金预计会将其大部分资产投资于剩余期限为一年（1年）或更短的美国国债、现金、现金等价物、“箱式价差”（可能包括投资于箱式价差ETF）以及提供对自动赎回指数敞口的未资金总收益互换（“互换协议”）。然而，为了满足互换协议的保证金要求，基金可能会将其所有或大部分现金分配到合格的抵押品工具上，例如：投资级固定收益和浮动利率债券；与政府和欧洲或美国投资级公司发行人发行的基准挂钩的可变利率票据；商业票据和货币市场基金。

每个自动赎回产品设计为在设定的每月观察日（“票息”）支付分配给该自动赎回产品的面值的一定百分比，前提是表现最差的成分在适用的观察日达到或超过预定水平（“票息障碍”）。如果在下文所述的不可赎回期结束后，指定的每月观察日表现最差的成分达到或超过预定水平（“自动赎回障碍”），则自动赎回产品将自动到期（被“赎回”）。如果在每月观察日表现最差的成分低于票息障碍（每个称为“观察日”），则该观察期不会支付票息；然而，每个自动赎回产品采用“记忆”（或“滚雪球”）功能，使得任何未支付的票息会累积并在（i）随后的每月观察日表现最差的成分再次达到或超过票息障碍时予以记入，或（ii）如果更早的话，在自动赎回产品被赎回时予以记入。例如，如果表现最差的成分在连续两个月的观察日低于票息障碍，但在第三个月的观察日达到或超过票息障碍，则第三个月的观察日将支付该月的票息以及之前未支付的两个月票息。

每个自动赎回产品自发行日起有一年的不可赎回期（“不可赎回期”）。每个自动赎回产品包含一项或有本金保护功能，因此，如果表现最差的成分股在预定到期日之前未导致自动赎回产品被赎回，那么在到期日表现最差的成分股的负面表现不会对自动赎回产品的本金回报产生任何负面影响，前提是到期时表现最差的成分股不低于某个预定水平（“到期门槛”）。只有在到期时表现最差的成分股低于该到期门槛时，自动赎回指数及随后的投资者才会在到期时面临表现最差的成分股的全部下行表现。因此，虽然在某些负面市场条件下自动赎回产品可能会保留本金（即，如果表现最差的成分股在到期时保持在或高于到期门槛），但股市的不利市场条件——特别是成分股出现大幅下跌或表现分化——可能导致基金出现负回报。

基金通过与一个或多个合格金融机构（“掉期交易对手”）签订一个或多个掉期协议来获得对自动赎回产品的敞口。这些掉期协议参考自动赎回指数，该指数旨在

CALAMOS 最低自动赎回收入 ETF

Calamos 最低自动赎回收入 ETF

反映整个指数投资组合的综合表现。通过这种方法，基金通过一个或多个衍生工具获得对自动赎回产品多样化组合的全面敞口。

鉴于基金将签订一个或多个无本金交割的总回报掉期，基金将面临变动保证金要求，并需要将其部分资产作为初始保证金进行抵押。除了上述内容外，基金预计还将投资于货币市场工具，包括美国国债、回购协议以及现金和现金等价物。基金还将利用由期权合约组合构成的箱式价差（“箱式价差”），其中包括合成多头头寸和通过期权合约组合的对冲合成空头头寸。基金还可能投资于其他主要投资于箱式价差的ETF。

基金可将其总资产的25%投资于一家全资子公司（“子公司”），该子公司根据开曼群岛法律设立。如果基金认为有必要或适当，对子公司的投资预计将在1986年《国内税收法典》（经修订）（“税法”）第M章和美国国税局指引的限制范围内，为基金提供对自动赎回指数的敞口。子公司主要投资于衍生工具，包括掉期协议。

投资结构概览。

该基金的投资策略核心是通过一个或多个参考自动赎回指数的互换协议，获得大约52至156个合成最少自动赎回产品的理论多样化组合的敞口。这些自动赎回产品中的每一个都与底层参考篮子中表现最差的成分（SPY、QQQ或IWM）的表现相关。为了有效实施这一策略，该基金与互换交易对手签订一个或多个互换协议。这些互换协议参考自动赎回指数，该指数旨在反映整个指数投资组合的综合表现，从而使基金能够通过每个互换交易对手的单一工具获得对理论合成最少自动赎回产品的全面敞口。收益基于下文“指数投资组合特性”部分中更详细描述的某些预定义的支付和回报特征。每个自动赎回产品的收益情况与底层参考篮子整体表现最差的成分相关，而不是查看任何成分所持有的个别证券。

由于每个自动赎回产品的票息、自动赎回和本金结果均参考表现最差的成分，因此参考三个成分的自动赎回产品通常比参考单一指数的类似自动赎回产品提供更高的票息，但需承担篮子分散风险——即一个成分可能明显落后于其他成分的风险。这是最少结构的核心权衡，下文“底层参考篮子——成分”部分有进一步说明。

该基金旨在通过ETF包装，提供一种历史上主要通过单独协商的结构化票据和场外合约向投资者提供的最少自动赎回收益策略的指数化实施方式。通过参考一个在总收益互换上交易的单一阶梯指数，而不是一组单独协商的票据或场外工具，该基金旨在相对于直接持有单独的最少票据或合约，提供标准化条款、每周阶梯式结构、更长的有效期限、更高效的定价和更高的税务效率。

指数投资组合特性

该基金为投资者提供对一个指数的敞口，该指数旨在反映大约52至156个合成最少自动赎回产品理论投资组合的综合总回报。指数投资组合中的每个自动赎回产品可能根据表现最差的成分的表现实现以下一种或两种支付和回报特征：

(a)

如果表现最差的成分的水平在指定观察日达到或高于票息障碍（如下所述），则在指定观察日获得固定的定期（每月）票息支付；

或

(b)

作为自动赎回产品回报的一部分，如果在到期时表现最差的成分的水平低于到期障碍，则自动赎回指数，进而该基金可能会受到表现最差的成分的负面表现的影响。

招募说明书 | 2026年10月14日

Calamos最少自动赎回收益ETF

指数投资组合中的每个自动赎回产品将具有以下关键特征/参数（“参数”）：

一、单个自动赎回产品：指数投资组合中的每个自动赎回产品具有（如下面的表格中更详细地说明）：

\n\n

•

3年期限（到期日）

\n\n

•	自发行日起1年的初始不可赎回期

\n\n

•

以美元计价

\n\n

•	70% 到期障碍（在到期时观察，应用于表现最差的成分股）

\n\n

•	100% 自动赎回障碍（每月观察，应用于表现最差的成分股）

\n\n

•	70% 票息障碍（每月观察，应用于表现最差的成分股）

\n\n

•	“记忆”（雪球）功能，未支付的票息将累积并在后续符合条件的每月观察日或在赎回时被计入

\n\n

•	收益参考底层参考篮子中最差表现的成分股（SPY、QQQ、IWM）

二、关键组成部分：指数投资组合中的每个自动赎回产品有四个主要组成部分：

\n\n

•	赎回功能：在每个自动赎回产品的不可赎回期到期后，如果在每月观察日，表现最差的成分股达到或超过自动赎回障碍，该自动赎回产品将在计划到期日之前自动被赎回。

\n\n

•	附条件票息：如果在每月观察日，表现最差的成分股处于或高于票息障碍，则每月向自动赎回产品支付票息。如果在观察日表现最差的成分股低于票息障碍，则该期间不会支付票息，但未支付的票息将累积，并在后续每月观察日，当表现最差的成分股再次处于或高于票息障碍时被计入（并且无论如何，在赎回时）。

\n\n

•	附条件本金保护：如果在到期前未赎回自动赎回产品，当到期时表现最差的成分股水平处于或高于到期障碍（70%）时，初始本金将得到完全保护。如果表现最差的成分股在到期时收盘低于到期障碍，该自动赎回产品的本金损失将等同于表现最差的成分股在整个自动赎回产品存续期内的负收益。

\n\n

•	记忆功能：如果在每月观察日表现最差的成分股低于票息障碍且未支付票息，该票息不会丢失，而是累积；所有之前未支付的票息将在（i）后续每月观察日，当表现最差的成分股再次处于或高于票息障碍时被计入，以及/或者（ii）如果更早的话，在自动赎回产品被赎回时被计入。

指数投资组合将每周重新平衡，采用每周滚动机制，即已自动赎回或到期的自动赎回产品将被新的自动赎回产品替换，任何支付的票息将重新投资于自动赎回产品。

三、实施机制：为了高效地获得对该理论多元化自动赎回产品组合的敞口，该基金利用：

\n\n

•	与交易对手的互换协议

\n\n

•	以自动赎回指数作为这些互换协议的参考，该指数旨在反映整个指数投资组合的综合表现。

一旦将自动赎回产品包含在指数投资组合中，该自动赎回产品的收益和回报特性将无法更改。因此，在每个自动赎回产品的收益过程中没有自由裁量权，因为该收益取决于在观察日篮子中表现最差的成分的表现是否低于到期障碍。关于到期障碍，如果在到期日，表现最差的成分的表现低于到期障碍，则偿还的本金金额将减少，如下例所示，这将对自动赎回指数的整体价值产生负面影响，进而对基金产生负面影响。

CALAMOS 最差成分自动赎回收入ETF

Calamos 最差成分自动赎回收入ETF

例如，注意自动赎回产品的到期障碍为该自动赎回产品发行日时最差成分水平的100%：

\n\n

•	如果最差成分仅下跌10%（这仍然高于到期障碍），那么最差成分的负面表现不会减少应偿还的本金金额；

\n\n

•	另一方面，如果最差成分下跌45%（即降至该自动赎回产品发行时水平的55%，低于到期障碍），那么在到期时应偿还的本金金额将减少45%。

由于基金通过掉期协议下的指数投资组合表现来接触自动赎回产品，因此指数投资组合中任何自动赎回产品的负面收益都将对自动赎回指数的水平产生负面影响，进而对基金产生负面影响。

下图说明了指数投资组合中单一合成最差成分自动赎回产品的收益情况，该收益取决于最差成分的表现。如果在每月观察日最差成分处于或高于票息障碍（即处于或高于其初始水平的70%），则会支付票息——通过记忆功能，还会支付之前错过的所有票息；如果最差成分低于该障碍，则不会支付票息。在不可赎回期之后，如果在每月观察日最差成分处于或高于其初始水平（100%），则会触发自动赎回。如果最差成分出现-30%的跌幅，将适用或有本金保护，超过该跌幅后，在到期时损失将与最差成分的表现一致。

单一合成最差成分自动赎回收入凭证的示例收益（不包括基金费用和开支）。虚线代表最差成分。仅用于说明；不表示任何自动赎回产品或基金的表现，也不一定表示实际的到期或票息障碍水平。

$\"\"$

组合管理与再平衡

自动赎回指数通过系统化流程进行管理，基金通过使用掉期协议来接触自动赎回指数。基础指数投资组合将每周进行再平衡，采用每周滚动方式

公开说明书 | 2026年10月14日

Calamos 最差成分自动赎回收入ETF

自动可赎回证券（Autocallables）在自动赎回或到期后会被新的自动可赎回证券替换，任何收到的票息都会被重新投资于自动可赎回证券。这种系统性方法旨在受益于（i）在不同市场周期中分散进入点；（ii）减少与单次投资相关的时机风险；以及（iii）保持对大约52至156个合成最低表现自动可赎回证券理论组合的一致性敞口。此外，通过借助自动可赎回指数对具有不同进入点的自动可赎回证券阶梯组合的总回报进行敞口，该基金旨在从一个理论上的多样化组合中获益，该组合旨在（i）在时间上平滑资本增值；（ii）减少任何单一市场进入点的集中风险；以及（iii）潜在降低整体组合波动性。

虽然自动可赎回指数遵循系统规则进行维护和替换，但顾问会主动监督掉期交易对手的敞口和信用状况、抵押品管理与优化、基金整体组合的风险特征以及掉期协议的执行质量和管理。由于该基金预计通过与多个掉期交易对手的掉期协议获得敞口，顾问还会监控基金名义掉期敞口在掉期交易对手之间的分配，并在容量、流动性和多样化需求出现时管理新增掉期交易对手的准入。

自动可赎回指数方法

自动可赎回指数旨在反映合成最低表现自动可赎回票据（“自动可赎回证券”）的理论组合的表现，其回报参考的是底层参考篮子中表现最差的成分股（SPY、QQQ或IWM）。理论组合中的自动可赎回证券遵循预定条款，包括从发行日起156周（3年）的到期期限、从发行日起52周（1年）的不可赎回期，以及每4周支付一次的票息。每个自动可赎回证券在特定的每月观察日具有条件现金流，支付取决于表现最差的成分股是否高于或低于特定阈值，包括100%的自动可赎回障碍和70%的本金和票息障碍百分比，同时还包括“记忆”功能，未支付的票息会累积并在后续符合条件的观察日或被赎回时进行计息。

自动可赎回指数提供方的定价模型会考虑当前市场状况，并考虑现金流的再投资，从而确定这些合成证券的现值。自动可赎回指数在预定时间间隔（每周）进行再平衡，每次再平衡日添加一个新的自动可赎回证券。为保持多样化，自动可赎回指数通过分配上限来应用集中度限制，将任何单个自动可赎回证券的权重限制在5%。已支付票息和到期或赎回证券的资金会根据预定义规则系统地重新分配到整个组合中。自动可赎回指数每日计算，每周再平衡，以美元计价，指数基础值设定为100。

该指数由具有以下特征的理论自动可赎回票据组合构成：

\n\n\n\n\n\n\n\n\n\n

规格 \n	自动赎回指数 \n
参考资产 \n	表现最差的 SPY、QQQ 和 IWM \n
面值 \n	100 \n
到期日 \n	自发行日起 156 周 \n
不可赎回期 \n	自发行日起 52 周 \n
红利支付日 \n	自发行日起每 4 周一次，直至到期日 \n
自动赎回障碍 \n	100% \n
本金障碍百分比 \n	70% \n
红利障碍百分比 \n	70% \n
记忆功能 \n	是 — 未支付的红利会在后续符合条件的观察期或赎回时计入 \n

Calamos 最差自动赎回收益 ETF

总收益互换 — 总收益互换是一种金融协议，双方约定一方根据固定或浮动利率向另一方支付单笔或定期支付，以换取基于标的资产总收益的单笔或定期支付，这包括资产产生的收入以及任何资本利得或损失。总收益互换也可用于在标的资产不可获得或基金无法拥有该资产的情况下获得市场敞口。\"总收益\"指的是标的参考资产的总收益的支付（或收取），然后与利率的收取（或支付）进行交换。如果标的资产的总收益超过或低于对冲利率义务，一方将向另一方支付或收取款项。总收益互换为基金提供了以更具成本效益的方式获得市场或行业指数敞口的额外灵活性。使用总收益互换可能会增加基金投资组合的杠杆率。

盒式价差 — 盒式价差是一种对冲期权组合，可能包括灵活交易所期权（“FLEX期权”）。盒式价差由一种合成多头头寸和一种通过同一参考资产在相同到期日的期权合约组合的对冲合成空头头寸组成。合成多头头寸包括（i）购买看涨期权和（ii）卖出看跌期权，每个都针对同一参考资产，且具有相同的行权价和到期日。合成空头头寸包括（i）购买看跌期权和（ii）卖出看涨期权，每个都针对同一参考资产，且到期日与合成多头头寸相同，但行权价与合成多头头寸不同。合成多头头寸和合成空头头寸的行权价之间的差异决定了盒式价差的到期价值（或到期时的价值）。盒式价差构建过程的一个重要特点是，它旨在消除与基础期权参考资产价格波动相关的市场风险。一旦盒式价差启动，其从启动日到到期日的收益将不会因基础期权参考资产的价格波动而改变。根据风险和收益的考虑，基金可能在各种指数或证券上购买盒式价差。预计盒式价差的收益特征类似于现金等价物。基金还可以投资于其他主要投资于盒式价差的ETF。

关于FLEX期权的一般信息

FLEX期权是可定制的、由期权清算公司（“OCC”）保证结算的交易所交易期权合约。OCC保证FLEX期权的每一方对手方的履约，成为“每个卖方的买方和每个买方的卖方”，以保护清算会员和期权交易者免受对手方风险的影响。如在基金的补充信息声明中更详细地描述，OCC可能对某些重大事件对FLEX期权进行调整。尽管由OCC保证结算，FLEX期权仍可能面临OCC的对手方风险，并且可能因破产或其他不利原因而无法履行FLEX期权的结算风险。基金将持有的参考SPDR S&P 500 ETF（“SPY”）的FLEX期权将使基金在期权到期日根据SPY的价值与行权价之间的差额，拥有接收或交付SPY份额的权利或义务，或者拥有接收或交付现金支付的权利或义务，具体取决于该期权是看跌期权还是看涨期权，以及基金是购买还是出售该期权。基金将购买看涨期权（使基金有权接收SPY份额或现金支付）和看跌期权（使基金有权交付SPY份额或现金支付），并在认为有必要或有益于构建箱式价差时，可能出售（即撰写）看涨期权（使基金有义务交付SPY份额或现金支付）和看跌期权（使基金有义务接收SPY份额或现金支付）。在购买的看涨期权和看跌期权实质上处于价内且箱式价差的合成多头和空头头寸可以有效构建而无需撰写看涨或看跌期权的情况下，基金可能会选择不撰写看涨或看跌期权。基金计划在构建箱式价差时使用FLEX期权。基金通过撰写FLEX期权获得期权费，通过购买FLEX期权支付期权费。OCC以及FLEX期权上市的证券交易所不会在期权合约存续期间对撰写者或购买者收取持续费用，但可能会收取交易费用。

招募说明书 | 2026年10月14日

Calamos最小值自动赎回收入ETF

标的参考篮子 — 组成部分

SPY

SPY 是一种交易所交易单位投资信托，采用复制策略，这意味着它尽可能投资于标准普尔 500® 指数中的尽可能多的股票。PDR Services, LLC（“PDR”）是 SPY 的发起人。SPY 的投资目标是在扣除费用前，一般与标准普尔 500® 指数（“指数”）的价格和收益率表现相对应。有关 SPY 的主要投资策略和风险的描述，请参见下方内容。您可以在以下网址在线找到 SPY 的招募说明书和其他有关该 ETF 的信息，包括附加信息声明和最近的股东报告：“https://www.ssga.com/us/en/intermediary/etfs/state-street-spdr-sp‑500-etf-trust-spy”。

以下关于 SPY 的摘要信息来自其向美国证券交易委员会（SEC）提交的文件。我们建议您参考 SPY 提交的 SEC 文件以及其他公开信息（例如 ETF 的年度报告），以了解 ETF 的业务和财务前景。以下关于 SPY 主要投资策略的描述直接摘自 SPY 于 2026 年 1 月 26 日发布的招募说明书（“SPY”指 SPY；其他定义的术语已进行修改，仅适用于本小节）。

SPY通过持有包含在指数（“组合”）中的普通股票组合来实现其投资目标，组合中每只股票的权重基本上与该股票在指数中的权重相对应。在SPY的说明书里，“组合证券”指的是SPY实际持有的构成SPY组合的普通股票，而“指数证券”指的是由指数提供商S&P Dow Jones Indices LLC（“S&P”）确定的包含在指数中的普通股票。在任何时候，SPY的组合将尽可能多地包含指数证券。为了保持组合证券和指数证券的构成和权重之间的对应关系，State Street Global Advisors Trust Company（“受托人”）或其母公司State Street Bank and Trust Company（“SSBT”）会不定期调整SPY的组合，以符合S&P对指数中指数证券的身份和/或相对权重的定期更改。受托人或SSBT会汇总这些调整，并至少每月一次，或在指数发生重大更改时更频繁地对SPY的组合进行更改。当SPY买卖证券（或“周转”其组合）时，可能会产生交易成本，例如经纪佣金。如果指数证券在指数中发生重大重新平衡，这些交易成本可能更高，这可能导致在SPY单位持有应税账户时产生更高的税款。这些成本未反映在SPY的估计年度信托普通运营费用中，会影响SPY的表现。在最近的财年中，SPY的组合周转率为组合平均价值的3%。SPY的组合周转率不包括通过处理SPY单位的创建或赎回而收到或交付的证券。组合周转率将取决于指数的变化以及SPY信托协议的要求。…尽管SPY可能在任何时候未能持有某些指数证券，但SPY通常会大量投资于指数证券，这应导致指数表现和SPY表现之间的紧密对应。…SPY不持有或交易期货或掉期，也不是商品基金。指数包含五百家（500）选定的公司，所有这些公司都在全国性证券交易所上市，并涵盖广泛的行业。…自1968年以来，该指数一直是美国商务部“领先指标”清单的一部分，用于跟踪美国经济的关键领域。有关指数市场价值的最新信息可从市场信息服务中获得。该指数的确定、组成和计算均不考虑SPY。

截至2026年9月30日，SPY在信息技术公司有重大投资。

QQQ

QQQ 是一种交易所交易的开放式管理投资公司。在 2025 年 12 月 19 日重新分类之前，该基金以单位投资信托的形式运作。QQQ 采用完全复制策略，这意味着它投资于纳斯达克-100 指数中的所有股票®。Invesco Capital Management LLC（“Invesco”）是 QQQ 的投资顾问。QQQ 的投资目标是力求跟踪纳斯达克-100 指数（“指数”）的投资结果，扣除费用和开支前®。有关 QQQ 的主要投资策略和风险的描述，请参见下文。您可以在“https://www.invesco.com/qqq-etf/en/about.html”在线找到 QQQ 的招股说明书和其他有关该 ETF 的信息。

以下关于 QQQ 的摘要信息来自其向美国证券交易委员会（SEC）提交的文件。我们敦促您参考 QQQ 提交的 SEC 文件以及其它公开信息（例如 QQQ 的年度报告）以了解 QQQ 的业务和财务前景。以下关于 QQQ 主要投资策略的描述直接摘自

CALAMOS 最低自动赎回收入 ETF

Calamos 最低自动赎回收入 ETF

QQQ 的招股说明书，日期为 2025 年 12 月 22 日，修订于 2026 年 6 月 10 日（“QQQ®” 指 QQQ；其他定义的术语已修改，并且仅适用于本小节）。

QQQ® 的投资目标是力求跟踪指数的投资结果，扣除费用和开支前。无法保证该投资目标能够完全实现。

Nasdaq, Inc.（“Nasdaq”或“指数提供商”）编制、维护和计算底层指数，该指数包括基于市值在纳斯达克证券市场有限责任公司上市的 100 家最大国内和国际非金融公司的证券。QQQ® 作为指数基金运作，不进行主动管理，这意味着它不寻求超越指数。该基金在寻求跟踪指数时采用“完全复制”方法，这意味着该基金按指数中各证券的权重比例投资于构成指数的所有证券。该指数涵盖了包括计算机硬件和软件、电信、零售/批发贸易和生物技术在内的主要行业组。该指数不包括金融公司，包括投资公司。

截至 2025 年 10 月 31 日，QQQ 在信息技术公司有重大投资。

IWM

IWM 是一种交易所交易基金，旨在跟踪 Russell 2000® 指数（“指数”）的投资结果，该指数是基于 FTSE Russell 定义的约 1,933 家在 Russell 3000® 指数中的最小发行人发行的权益证券的流通股调整市值加权指数。

IWM 是一家根据1940年法案在证券交易委员会（SEC）注册的开放式管理投资公司。IWM 使用一种复制策略，意味着它尽可能多地投资于罗素2000® 指数中的股票。贝莱德基金顾问公司（“BFA”）是 IWM 的投资顾问。您可以在 “https://www.ishares.com/us/products/239710/ishares‑russell‑2000‑etf” 网站上找到 IWM 的招募说明书和其他有关该ETF的信息，包括附加信息声明和最近的股东报告。

以下关于 IWM 的摘要信息来自其向证券交易委员会（SEC）提交的文件。我们建议您参考 IWM 提交的 SEC 文件和其他公开信息（例如该ETF的年度报告），以了解该ETF的业务和财务前景。以下关于 IWM 主要投资策略的描述直接摘自 IWM 于2026年7月31日发布的招募说明书（定义的术语已进行修改，仅适用于本小节）。

IWM 通过持有包含在指数中的普通股票（“投资组合”）来实现其投资目标，投资组合中每只股票的权重基本上与该股票在指数中的权重相对应。

截至2026年3月31日，该指数约占罗素3000® 指数总市值的5%，该指数的大部分由金融、医疗和工业行业或部门的公司证券组成。基础指数的组成部分可能会随时间而变化。

为了保持投资组合证券与指数证券之间的组成和权重对应关系，BFA 会不时调整 IWM 的投资组合，以符合罗素对指数证券的身份和/或相对权重的定期调整。当 IWM 买卖证券（或“调换”其投资组合）时，可能会产生交易成本，例如佣金。较高的投资组合调换率可能表明交易成本较高，并且在基金股份持有于应税账户时可能导致更高的税负。这些成本未反映在年度基金运营费用或示例中，会影响 IWM 的表现。在最近的财年中，IWM 的投资组合调换率为平均投资组合价值的18%。

尽管 IWM 在任何时候可能不持有某些指数证券，但 IWM 通常会大量投资于指数证券，这应使指数的表现与 IWM 的表现紧密对应。IWM 不使用期货、期货期权或证券期权进行投机，并不是一个商品基金。指数的确定、组成和计算均不考虑 IWM。

招募说明书 | 2026年10月14日

卡拉莫斯最小值自动赎回收入ETF

主要风险

对基金的投资存在风险，您可能在基金投资中亏损。无法保证基金能够实现其投资目标。如果您投资的目标与基金的投资目标不同，或者您不愿意承担与基金投资相关的本金风险，那么您不应考虑投资于该基金。在市场剧烈波动时期，与基金投资相关的风险可能会增加。您对基金的投资不是银行存款，也不受联邦存款保险公司或任何其他政府机构的保险或担保。为了便于查找特定风险并与其他基金进行比较，主要风险按字母顺序排列。以下列出的每项风险都被视为投资于该基金的“主要风险”，无论其出现的顺序如何。投资于该基金的主要风险包括：

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•	授权参与者集中风险 — 只有授权参与者可以与基金直接进行创建或赎回交易，且这些授权参与者中没有哪一个有义务进行创建和/或赎回交易。

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•	自动赎回结构风险 — 基金的收益与反映在自动赎回指数中的理论自动赎回组合的表现相关。自动赎回票据具有特定的结构特征，可能对许多投资者来说是不熟悉的。

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•	或有收入风险 — 自动赎回的票息支付没有保证，如果在观察日最差表现的成分股低于票息障碍（70%），则不会支付票息。这意味着在市场下跌期间，基金可能产生的收入远低于预期。

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•	提前赎回风险 — 如果在观察日最差表现的成分股达到或超过自动赎回障碍，指数组合中的自动赎回票据可能在计划到期前被赎回。如果市场收益率下降，这可能导致该指数组合的一部分被迫以较低利率重新投资。

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•	障碍风险 — 如果在自动赎回票据到期时最差表现的成分股低于到期障碍（70%），该指数组合的该部分将完全暴露于最差表现成分股的负面表现，从其初始水平开始计算。例如，如果某只自动赎回票据到期时最差表现的成分股下跌了45%，那么该票据分配到指数组合的部分将损失45%的价值。这种条件性保护会产生二元结果，如果障碍被突破，可能导致突然且重大的损失。

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•	组合分散与相关性风险 — 由于基金的下行风险与三个不同指数（SPY、QQQ 和 IWM）中最差表现的资产相关，出现障碍突破的统计概率高于如果基金仅跟踪单一指数的情况。简而言之，只要一个指数出现严重局部下跌（例如，通过 IWM 表现的小盘股），即使其他两个指数表现优异，该基金组合的该部分也将遭受全部本金损失。

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跨式组合风险 — 如果在期权合约到期前，单独修改或平仓构成跨式组合的某个或某些期权头寸，那么跨式组合可能不再能有效消除与标的参考资产价格波动相关的风险。此外，跨式组合的价值在市场中确定，部分取决于组成跨式组合的期权到期时间以及当前市场利率。该基金有效利用跨式组合的能力取决于其他市场参与者是否愿意以有竞争力的价格向基金出售跨式组合。如果跨式组合未能按预期运作，该基金可能会面临组成跨式组合的期权所对应的标的参考资产的风险，该资产预计为SPY。在这种情况下，该基金将面临权益证券市场的风险。权益证券价格波动的原因包括投资者对发行人财务状况或相关权益市场整体状况的看法变化，例如市场波动，或影响发行人的政治或经济事件发生时。

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•	计算方法风险 — 自动敲入指数采用复杂的计算方法，在某些市场条件下可能无法按预期运行。

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•	现金持仓风险 — 该基金持有现金头寸的范围越大，基金面临获得较低收益和潜在错过参与市场增值机会的风险，这可能对基金的表现和实现其投资目标的能力产生负面影响。

CALAMOS LEAST-OF AUTOCALLABLE INCOME ETF

Calamos Least-Of Autocallable Income ETF

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•	相关性风险 — 由于多种原因，该基金的回报很可能无法与指数组合的预期回报或自动敲入指数的回报相匹配，包括向投资者支付定期分配、运营费用、交易成本、现金管理、市场状况以及计算方法的差异。

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•	买卖基金份额的成本 — 由于买卖基金份额的成本，包括经纪人收取的经纪佣金和买卖价差，频繁交易基金份额可能会显著降低投资回报，因此对于计划经常进行小额投资的投资者来说，投资基金份额可能并不合适。

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•	对手方风险 — 基金将面临与衍生品合约（主要是互换协议）交易对手的信用风险。基金对指数投资组合的敞口完全通过与互换交易对手的互换协议获得。如果一个互换交易对手破产或以其他方式未能履行其义务，基金可能会在获得任何赔偿方面遇到重大延误，可能只能获得有限的赔偿，或者可能根本无法获得赔偿。与直接持有的证券不同，基金的持仓主要是在互换交易对手上的合同索赔，这使基金特别容易受到交易对手失败的影响。即使互换交易对手在互换协议下的履约能力出现暂时中断，也可能对基金表现产生重大影响。基金可能对单一互换交易对手有重大敞口，这可能导致基金更容易受到影响该互换交易对手的单一经济或监管事件的影响。

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•	信用风险 — 基金的抵押投资可能面临信用风险，即发行人或交易对手未能按时支付本金或利息的风险。

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•	衍生品风险 — 衍生品是诸如互换、期权、期货和远期外汇合约等工具，其价值来源于其他资产、利率或指数。衍生品可用于对冲（通过用另一种投资头寸抵消一种投资头寸以尝试降低风险）或非对冲目的。将衍生品用于非对冲目的可能比其他类型的投资更具投机性。使用衍生品将增加费用和波动性，且无法保证衍生品策略会按预期运作。衍生品价值的变化可能与基础资产、利率或指数不完全相关，基金可能损失超过投资的本金金额。

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•	权益证券风险 — 证券市场是波动的。基金对表现最差的构成部分的敞口使其面临与权益市场相关的风险。由于影响美国权益市场整体或市场特定部分的因素，表现最差的构成部分的价值可能会波动，有时会迅速且不可预测地波动。如果表现最差的构成部分所涉及的证券的市场价格下跌，您在基金中的投资价值也将下跌。

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FLEX 期权风险 — 交易 FLEX 期权涉及与直接投资于证券或其他类型期权不同的风险，可能更大。FLEX 期权与其它上市期权一样，在美国期权市场交易，并由 OCC 发行。然而，与其它期权不同，FLEX 期权的条款并非全部标准化。当 FLEX 期权在开仓交易中被购买和出售时，交易双方在期权市场规则规定的限制内，可以固定期权的某些条款。能够固定某些条款的灵活性是 FLEX 期权与其他类型期权不同的原因。由于 FLEX 期权的许多条款未标准化，因此不太可能有一个活跃的二级市场，使得此类期权的持有者和卖方能够通过抵消买卖来平仓。由于 FLEX 期权的条款是双方固定的，因此不存在预设的 FLEX 期权系列。相反，由于不同交易中对可变条款的不同指定，任何不同的 FLEX 期权系列都可能在任何时候被创建并处于流通状态。因此，FLEX 期权的二级交易兴趣可能分散在比其他期权更多的系列中，任何特定系列的 FLEX 期权的交易兴趣可能非常有限，FLEX 期权的二级市场可能不如相同基础资产的其他期权市场那样深度、流动性和连续性。此外，FLEX 期权的期权费可能与这些其他期权的期权费不相关。如果 FLEX 期权的交易受到限制或不存在，基金的 FLEX 期权价值可能会下降。在 FLEX 期权市场流动性较差的情况下，平仓 FLEX 期权可能需要支付溢价（对于卖出的 FLEX 期权）或接受

招股说明书 | 2026 年 10 月 14 日

Calamos 最少值自动赎回收入 ETF

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discounted price (for purchased FLEX Options) and may take longer to complete. A less liquid trading market may adversely impact the value of the FLEX Options and Fund Shares and result in the Fund being unable to achieve its investment objective. Less liquidity in the trading of the Fund’s FLEX Options could have an impact on the prices paid or received by the Fund for the FLEX Options in connection with creations and redemptions of the Fund Shares. Depending on the nature of this impact to pricing, the Fund may be forced to pay more for redemptions (or receive less for creations) than the price at which it currently values the FLEX Options. Such overpayment or under collection may impact the value of the Fund and whether the Fund can satisfy its investment objective. Additionally, in a less liquid market for the FLEX Options, the liquidation of a large number of options may more significantly impact the price. A less liquid trading market may adversely impact the value of the FLEX Options and the value of your investment. The trading in FLEX Options may be less deep and liquid than the market for certain other exchange-traded options, non-customized options or other securities. The Fund also is subject to the risk that the OCC will become insolvent or otherwise be unable to meet its obligations, which could cause the Fund to suffer losses which may be significant.

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Index Risk — There can be no guarantee that the Autocallable Index will be maintained indefinitely or that the Fund will be able to continue to utilize the Autocallable Index to implement the Fund’s principal investment strategies indefinitely. If necessary, the Adviser or the Fund’s Board of Trustees may substitute the Autocallable Index with another index that it chooses in its sole discretion and without advance notice to shareholders. There can be no assurance that any substitute index so selected will perform in a manner similar to the Autocallable Index, as applicable. Unavailability of the index could affect adversely the ability of the Fund to achieve its investment objective.

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•	Interest Rate Risk — The value of the Fund’s fixed-income investments may be affected by changes in interest rates. When interest rates rise, the value of fixed-income investments generally falls.

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Investment in a Subsidiary — As determined necessary or advisable by the Fund, the Fund may invest a portion of its assets in a wholly-owned subsidiary (each, a “Subsidiary”), organized under the laws of the Cayman Islands. Investment in the Subsidiary is expected to provide the Fund with exposure to the Autocallable Index within the limitations of Subchapter M of the Code and Internal Revenue Service guidance. The Subsidiary may invest primarily in derivative instruments, including Swap Agreements. To the extent that the Fund invests in the Subsidiary, the Fund may be subject to the risks associated with the above-mentioned derivative instruments and other securities, which are discussed elsewhere in the Fund’s Prospectus and Statement of Additional Information (“SAI”). To comply with the asset diversification test applicable to a RIC (discussed in the SAI), the Fund intends to limit its investments in such subsidiary to 25% of the Fund’s total assets at the end of each taxable quarter.

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Laddered Portfolio Risk — The laddered portfolio strategy may not perform as expected if market conditions remain unfavorable over an extended period, multiple Autocallable instruments may experience losses simultaneously and/or the weekly rebalancing mechanism may result in suboptimal entry points during rapidly changing markets.

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•	Liquidity Risk — Liquidity risk exists when particular investments are difficult to purchase or sell. The Fund’s investments in illiquid securities may reduce the returns of the Fund because it may be unable to sell the illiquid securities at an advantageous time or price.

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Market Maker Risk — If the Fund has lower average daily trading volumes, it may rely on a small number of third-party market makers to provide a market for the purchase and sale of Fund Shares. Any trading halt or other problem relating to the trading activity of these market makers could result in a dramatic change in the spread between the Fund’s net asset value and the price at which the Fund Shares are trading on the Exchange, which could result in a decrease in value of the Fund Shares. In addition, decisions by market makers or authorized participants to reduce their role or step away from these activities in times of market stress could inhibit the effectiveness of the arbitrage process in maintaining the relationship between the underlying values of the Fund’s portfolio securities and the Fund’s market price. This reduced

CALAMOS LEAST-OF AUTOCALLABLE INCOME ETF

Calamos Least-Of Autocallable Income ETF

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effectiveness could result in Fund Shares trading at a discount to net asset value and also in greater than normal intra-day bid-ask spreads for Fund Shares.

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•	Market Risk — The risk that the securities markets will increase or decrease in value is considered market risk and applies to any security, including those held by the Index Portfolio.

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•	New Fund Risk — The Fund is a recently organized investment company with a limited operating history. As a result, prospective investors have a limited track record or history on which to base their investment decision.

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Non-Diversification Risk — The Fund is classified as “non-diversified” under the 1940 Act. As a result, the Fund is only limited as to the percentage of its assets which may be invested in the securities of any one issuer by the diversification requirements imposed by the Code. In addition, this makes the Fund more susceptible to risks associated with a single economic, political, or regulatory occurrence.

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Other Investment Companies Risk — The Fund may invest in the securities of other investment companies to the extent that such investments are consistent with the Fund’s investment objectives and permissible under the 1940 Act. Under one provision of the 1940 Act, the Fund may not acquire the securities of other investment companies if, as a result, (i) more than 10% of the Fund’s total assets would be invested in securities of other investment companies, (ii) such purchase would result in more than 3% of the total outstanding voting securities of any one investment company being held by the Fund or (iii) more than 5% of the Fund’s total assets would be invested in any one investment company. In some instances, the Fund may invest in an investment company in excess of these limits. For example, the Fund may invest in other registered investment companies, such as mutual funds, closed-end funds and exchange-traded funds (“ETFs”), including affiliated funds, and in business development companies in excess of the statutory limits imposed by the 1940 Act in reliance on Rule 12d1‑4 under the 1940 Act. These investments would be subject to the applicable conditions of Rule 12d1‑4, which in part would affect or otherwise impose certain limits on the investments and operations of the underlying fund. The Fund, as a holder of the securities of other investment companies, will bear its pro rata portion of the other investment companies’ expenses, including advisory fees. These expenses will be in addition to the direct expenses incurred by the Fund. In the event the Fund invests in another affiliated fund (the “Acquired Fund”), the portion of the Fund’s Investment Management Fee equal to the advisory fee payable to the Acquired Fund (based on average daily net assets invested) is waived.

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Premium-Discount Risk — Fund Shares may trade above or below their NAV. The market prices of Fund Shares will generally fluctuate in accordance with changes in NAV as well as the relative supply of, and demand for, Fund Shares on the Exchange. The trading price of Fund Shares may deviate significantly from NAV during periods of market volatility.

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Secondary Market Trading Risk — Investors buying or selling Fund Shares in the secondary market will pay brokerage commissions or other charges imposed by brokers as determined by that broker. Brokerage commissions are often a fixed amount and may be a significant proportional cost for investors seeking to buy or sell relatively small amounts of Fund Shares. Although the Fund Shares are listed on the Exchange, there can be no assurance that an active or liquid trading market for them will develop or be maintained. The Fund’s shares may trade at prices substantially different from NAV during periods of market stress or when the complex underlying derivatives are difficult to value. In addition, trading in Fund Shares on the Exchange may be halted.

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PROSPECTUS | October 14, 2026

Calamos Least-Of Autocallable Income ETF

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be initiated by the Board of Trustees without a shareholder vote. While shareholder interests will be the paramount consideration in a liquidation under such circumstances, the timing of the liquidation may not be favorable to certain individual shareholders.

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Tax Risk — The Fund intends to elect and to qualify each year to be treated as a regulated investment company (“RIC”) under Subchapter M of the Code. To qualify and maintain its status as a RIC, the Fund must derive at least 90% of its gross income each year from “qualifying income,” meet certain diversification tests at the end of each quarter and meet an annual distribution test. For purposes of the qualifying income requirement, the treatment of the swaps and other derivatives that provide exposure to the Autocallables is not entirely clear, and thus whether the income and gain therefrom is qualifying income is uncertain. If the Fund were to treat income or gain from particular instruments linked to the Autocallables as qualifying income, an adverse determination or future guidance by the Internal Revenue Service with respect to the treatment of income or gain from those investments may adversely affect the Fund’s ability to qualify as a RIC. For purposes of the diversification test, the identification of the issuer (or, in some cases, issuers) of a particular Fund investment can depend on the terms and conditions of that investment. In particular, there is no published Internal Revenue Service guidance or case law on how to determine the “issuer” of certain derivatives that the Fund will enter into. An adverse determination or future guidance by the Internal Revenue Service with respect to issuer identification for the Fund’s investments may adversely affect the Fund’s ability to qualify as a RIC. If the Fund does not qualify as a RIC for any taxable year and certain relief provisions are not available, the Fund’s taxable income will be subject to tax at the Fund level and to a further tax at the shareholder level when such income is distributed.

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The federal income tax treatment of the swaps and other derivatives (including the options comprising the Box Spreads) may not be as favorable as a direct investment in an underlying asset and may adversely affect the timing, character and amount of income the Fund realizes from its investments. As a result, a larger portion of the Fund’s distributions may be treated as ordinary income rather than capital gains. In addition, certain derivatives are subject to mark-to-market or straddle provisions of the Code. If such provisions are applicable, there could be an increase (or decrease) in the amount of taxable dividends paid by the Fund.

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Trading Issues Risk — Trading in Fund Shares on the Exchange may be halted due to market conditions or for reasons that, in the view of the Exchange, make trading in shares inadvisable. Further, there can be no assurance that the requirements of the Exchange necessary to maintain the listing of the Fund will continue to be met or will remain unchanged.

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Valuation Risk — The complex nature of autocallable structures and volatility-targeted indices may make accurate valuation difficult during market stress, potentially leading to significant premiums or discounts to NAV. In addition, during periods of reduced market liquidity or in the absence of readily available market quotations for the holdings of the Fund, the ability of the Fund to value the Swap Agreements may become more difficult.

Fund Performance

The Fund has not commenced operations as of the date of this prospectus. Once available, the Fund’s performance information, and information that gives some indication of the risks of an investment in the Fund by comparing the Fund’s performance with a broad measure of market performance, will be available at no cost by visiting the Fund’s website at www.calamos.com. Past performance (before and after taxes) is not an indication of future performance.

Investment Adviser

Calamos Advisors LLC (“Calamos Advisors” or the “Adviser”)

Portfolio Managers

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PORTFOLIO MANAGER/ FUND TITLE (IF APPLICABLE) \n	PORTFOLIO MANAGER EXPERIENCE IN THE FUND \n	PRIMARY TITLE WITH ADVISER \n
Shaheen Iqubal \n	Since October 14, 2026 \n	SVP, Co-Portfolio Manager \n
Jordan Rosenfeld \n	Since October 14, 2026 \n	VP, Co-Portfolio Manager \n

CALAMOS LEAST-OF AUTOCALLABLE INCOME ETF

Other Important Information Regarding Fund Shares

Portfolio Holdings. The Fund’s portfolio holdings will be disclosed on its website daily after the close of trading on the Exchange and prior to the opening of trading on the Exchange the following day. A description of the Fund’s policies and procedures with respect to the disclosure of the Fund’s portfolio holdings is available in the Fund’s Statement of Additional Information (“SAI”).

Premium/Discount Information. Information about the premiums and discounts at which the Fund’s Shares have traded will be available at www.calamos.com.

Purchase and Sale of Fund Shares

The Fund will issue (or redeem) Fund Shares to certain institutional investors (typically market makers or other broker-dealers) only in large blocks of Fund Shares known as “Creation Units.” Creation Unit transactions are conducted in exchange for the deposit or delivery of a designated portfolio of in-kind securities and/or cash.

Individual Fund Shares may only be purchased and sold on the Exchange, other national securities exchanges, electronic crossing networks and other alternative trading systems through your broker-dealer at market prices. Because Fund Shares trade at market prices rather than at net asset value (“NAV”), Fund Shares may trade at a price greater than NAV (premium) or less than NAV (discount). When buying or selling Fund Shares in the secondary market, you may incur costs attributable to the difference between the highest price a buyer is willing to pay to purchase Fund Shares (bid) and the lowest price a seller is willing to accept for Fund Shares (ask) (the “bid-ask spread”). Recent information regarding the Fund’s NAV, market price, premiums and discounts, and bid-ask spreads is available at https://www.calamos.com/.

Tax Information

Net investment income and capital gains distributions you receive from the Fund generally are subject to federal income taxes and may also be subject to state and local taxes. The Fund intends to make distributions monthly and distribute long-term capital gains, if any, at least annually.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase shares of the Fund through a broker-dealer or other financial intermediary (such as a bank), the Fund and its related companies may pay the intermediary for the sale of Fund Shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary’s website for more information.

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Additional Information About Investment Strategies
and Related Risks

The Fund’s investment objective and each of the policies described herein are non-fundamental policies that may be changed by the Board of Trustees of the Trust (the “Board”) without shareholder approval. The Fund may liquidate and terminate at any time without shareholder approval.

What are the investment objectives and principal strategies for the Fund?

Principal Investment Strategies

The Fund is a non-diversified, actively managed exchange-traded fund (“ETF”) that, under normal market conditions, seeks to invest at least 80% of its total assets in U.S. Treasuries, cash, cash equivalents, “box spreads” (including box spread ETFs) and unfunded total return swaps that provide exposure to the MerQube US Equity Least-Of Autocallable Index (the “Autocallable Index”). The Fund will not attempt to replicate or track the Autocallable Index but will instead use financial instruments such as total return swaps to gain exposure to the level of the Autocallable Index. The Fund intends to make distributions to investors monthly in amounts that are determined in part by reference to the Autocallable Index. The Autocallable Index is designed to reflect the collective performance of a theoretical portfolio of approximately 52 to 156 synthetic least-of autocallable notes arranged in a laddered structure with staggered entry points and similar fixed parameters (the “Parameters”) as described below within the section entitled “Index Portfolio Characteristics.”

The Autocallables’ coupon payments, principal repayment timing and principal value at maturity, and ultimately the Fund’s total return, are contingent and, with respect to principal value at maturity, based on the performance of the least-performing Constituent Index (SPY, QQQ, or IWM) of the Underlying Reference Basket (basket which consists of SPY, QQQ, and IWM). At each Observation Date, the “least-performing Constituent” — that is, the Constituent with the lowest performance relative to its level at the time the applicable Autocallable was included in the Index Portfolio — determines the coupon, autocall and principal outcomes for that Autocallable. The Fund expects to invest substantially all of its assets in U.S. Treasury securities with remaining maturities of one (1) year or less, cash, cash equivalents, “box spreads” (which may include investment in box-spread ETFs) and unfunded total return swaps providing exposure to the Autocallable Index (the “Swap Agreements”). However, in order to meet its margin requirements on the Swap Agreements, the Fund may allocate all or a significant portion of its cash to investments in eligible collateral instruments such as: investment-grade fixed income and floating rate bonds; notes with variable interest rates tied to benchmarks issued by governments and European or U.S. investment-grade corporate issuers; commercial paper and money market funds.

Each Autocallable is designed to pay a percentage of the notional amount allocated to that Autocallable at set monthly Observation Dates (a “Coupon”), provided that the least-performing Constituent is at or above a predetermined level (the “Coupon Barrier”) on the applicable Observation Date. If, on a specified monthly Observation Date and following the expiration of the Non-Callable Period described below, the least-performing Constituent is at or above a predetermined level (the “Autocallable Barrier”), then the Autocallable will automatically mature (be “called”). If the least-performing Constituent is below the Coupon Barrier on a monthly Observation Date, no Coupon is then-paid for that then-ended observation period; however, each Autocallable employs a “memory” (or “snowball”) feature whereby any such unpaid Coupons accumulate and are credited (i) on a subsequent monthly Observation Date on which the least-performing Constituent is again at or above the Coupon Barrier, and/or (ii) if earlier, upon the Autocallable being called. For example, if the least-performing Constituent is below the Coupon Barrier on two consecutive monthly Observation Dates but is at or above the Coupon Barrier on the third, the Coupon for the third Observation Date is paid together with the two Coupons that had previously been skipped.

Each Autocallable is subject to a one-year non-callable period from the date of issuance (the “Non-Callable Period”). Each Autocallable incorporates a contingent principal protection feature so that, if the least-performing Constituent has not caused the Autocallable to be called before the scheduled maturity date, any negative performance of the least-performing Constituent as at the maturity date will not have any negative impact on the return of principal under the Autocallable, provided the least-performing Constituent is not below a certain predetermined level at maturity (the “Maturity Barrier”). Only if the least-performing Constituent is below that Maturity Barrier at maturity will the Autocallable Index, and in turn investors, be exposed to the full downside performance of the least-performing Constituent at maturity. Therefore, while Autocallables may preserve capital in certain negative market conditions (i.e., if the least-performing Constituent remains at or above the

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Additional Information About Investment Strategies and Related Risks

Maturity Barrier), adverse market conditions in the equity market — and in particular a significant decline in, or divergence in the performance among, the Constituents — can lead to negative returns for the Fund.

The Fund’s exposure to the Autocallables is obtained through one or more Swap Agreements with one or more qualified financial institutions (“Swap Counterparties”). These Swap Agreements reference the Autocallable Index, which is designed to reflect the aggregate performance of the entire Index Portfolio. Through this approach, the Fund obtains comprehensive exposure to the diversified portfolio of Autocallables via one or more derivative instruments.

In light of the fact that the Fund is entering into one or more unfunded total return swaps, the Fund will be subject to variation margin requirements and will be required to post a portion of its assets as initial margin. In addition to the above, the Fund expects to invest in money market instruments, including U.S. Treasury Securities and repurchase agreements as well as cash and cash equivalents. The Fund will also utilize box spreads that consist of a synthetic long position coupled with an offsetting synthetic short position through a combination of options contracts (“Box Spreads”). The Fund may also invest in other exchange-traded funds which in turn invest principally in Box Spreads.

The Fund may invest up to 25% of its total assets in a wholly-owned subsidiary (a “Subsidiary”), organized under the laws of the Cayman Islands. If determined necessary or advisable by the Fund, investment in the Subsidiary is expected to provide the Fund with exposure to the Autocallable Index within the limitations of Subchapter M of the Internal Revenue Code of 1986, as amended (the “Code”) and Internal Revenue Service guidance. The Subsidiary may invest primarily in derivative instruments, including Swap Agreements.

Investment Structure Overview.

The Fund’s investment approach centers on gaining exposure to a theoretical diversified portfolio of approximately 52 to 156 synthetic least-of autocallables using one or more Swap Agreements that reference the Autocallable Index. Each of these Autocallables is linked to the performance of the least-performing Constituent (SPY, QQQ and IWM) of the Underlying Reference Basket. To efficiently implement this strategy, the Fund enters into one or more Swap Agreements with Swap Counterparties. These Swap Agreements reference the Autocallable Index, which is designed to reflect the aggregate performance of the entire Index Portfolio, allowing the Fund to gain comprehensive exposure to a theoretical portfolio of synthetic least-of Autocallables through a single instrument per Swap Counterparty. The returns are based on certain pre-defined payout and return characteristics described in more detail in the section below entitled “Index Portfolio Characteristics.” Each Autocallable’s return profile is linked to the least-performing Constituent of the Underlying Reference Basket as a whole and does not look through to the individual securities held by any Constituent.

Because the coupon, autocall and principal outcomes of each Autocallable are determined by reference to the least-performing Constituent, an Autocallable referencing a basket of three Constituents generally offers a higher Coupon than an otherwise-comparable autocallable referencing a single index, in exchange for basket dispersion risk — the risk that one Constituent materially underperforms the others. This is the central trade-off of the least-of structure and is described further under “The Underlying Reference Basket — Constituents” below.

The Fund is designed to deliver, in an ETF wrapper, an indexed implementation of a least-of autocallable income strategy that has historically been offered to investors principally through individually negotiated structured notes and over-the-counter contracts. By referencing a single laddered index that is traded on total return swap — rather than a portfolio of separately negotiated notes or OTC instruments — the Fund seeks to provide standardized terms, weekly laddering, longer effective maturities, more efficient pricing and greater tax efficiency relative to holding individual least-of notes or contracts directly.

Index Portfolio Characteristics

The Fund provides investors with exposure to an index which is designed to reflect the aggregate total return of a theoretical portfolio of approximately 52 to 156 synthetic least-of Autocallables. Each Autocallable in the Index Portfolio may achieve one or both of the following payout and return characteristics depending on the performance of the least-performing Constituent:

(a)

fixed periodic (monthly) Coupon payments on specified Observation Dates if the level of the least-performing Constituent is at or above the Coupon Barrier (as set forth below);

PROSPECTUS | October 14, 2026

Additional Information About Investment Strategies and Related Risks

(b)

as part of the Autocallables’ return, the Autocallable Index, and in turn the Fund may be exposed to the negative performance of the least-performing Constituent in case the level of such least-performing Constituent is below the Maturity Barrier at maturity.

Each Autocallable in the Index Portfolio will have the following key characteristics/parameters (the “Parameters”):

I. Individual Autocallables: Each Autocallable in the Index Portfolio features (as more set forth in the table below):

•

3-year tenor (Maturity)

•

1-year initial Non-Callable Period from the date of issuance

•

U.S. Dollar denomination

•

70% Maturity Barrier (observed at maturity, applied to the least-performing Constituent)

•

100% Autocallable Barrier (observed monthly, applied to the least-performing Constituent)

•

70% Coupon Barrier (observed monthly, applied to the least-performing Constituent)

•

A “memory” (snowball) feature whereby unpaid Coupons accumulate and are credited on a later qualifying monthly Observation Date or upon call

•

Return determined by reference to the least-performing Constituent (SPY, QQQ, IWM) of the Underlying Reference Basket

II. Key Components: Each Autocallable in the Index Portfolio has four main components:

•

Call Feature: Upon the expiration of each Autocallable’s Non-Callable Period, the Autocallable will automatically be called prior to its scheduled maturity date if the least-performing Constituent reaches or exceeds the Autocallable Barrier on a monthly Observation Date.

•

Contingent Coupon: A Coupon is paid monthly on the Autocallable if, on the monthly Observation Date, the least-performing Constituent is at or above the Coupon Barrier. If the least-performing Constituent falls below the Coupon Barrier on an Observation Date, no Coupon will be paid for that period, but any unpaid Coupons accumulate and are credited on a subsequent monthly Observation Date on which the least-performing Constituent is again at or above the Coupon Barrier (and, in any event, upon call).

•

Contingent Principal Protection: If an Autocallable is not called prior to Maturity, the initial principal is fully protected if the least-performing Constituent’s level is at or above the Maturity Barrier (70%) at maturity. If the least-performing Constituent closes below the Maturity Barrier, principal loss for that Autocallable will be equivalent to the negative performance of the least-performing Constituent measured over the life of the Autocallable.

•

Memory: If the least-performing Constituent is below the Coupon Barrier on a monthly Observation Date and no Coupon is paid, that Coupon is not lost but instead accumulates; all such previously unpaid Coupons are credited (i) on a subsequent monthly Observation Date on which the least-performing Constituent is again at or above the Coupon Barrier, and/or (ii) if earlier, upon the Autocallable being called.

The Index Portfolio will be rebalanced weekly, employing a weekly roll mechanism whereby Autocallables that have auto called or matured are replaced with new Autocallables and any Coupons paid are reinvested in Autocallables.

III. Implementation Mechanism: To efficiently gain exposure to this theoretical diversified portfolio of Autocallables, the Fund utilizes:

•

Swap Agreements with Swap Counterparties

•

The Autocallable Index as a reference for these Swap Agreements, which is designed to reflect the aggregate performance of the entire Index Portfolio.

Once an Autocallable has been included in the Index Portfolio, the payout and return characteristics for such Autocallable can no longer be changed.

Therefore, there is no discretion involved in the payout process for each Autocallable, as such payout depends on whether the performance of the least-performing Constituent in the Basket on the Observation Date is below the Maturity Barrier. With

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Additional Information About Investment Strategies and Related Risks

regard to the Maturity Barrier, if on the Maturity Date the performance of the least-performing Constituent is below the Maturity Barrier, the amount of principal repaid will be reduced, as per the example below, which will negatively impact the overall value of the Autocallable Index and, in turn, the Fund.

For example, noting the Maturity Barrier for an Autocallable is 100% of the level of the least-performing Constituent as of the date the Autocallable is issued:

•

if the least-performing Constituent falls by only 10% (which is still above the Maturity Barrier) then the negative performance of the least-performing Constituent will not reduce the amount of principal to be repaid;

•

on the other hand, if the least-performing Constituent falls by 45% (i.e., to 55% of the level it was at when the Autocallable was issued and which is below the Maturity Barrier), then at maturity the amount of principal to be repaid will have fallen by 45%.

As the Fund is exposed to the Autocallables through the performance of the Index Portfolio under the Swap Agreement(s), any negative return of an Autocallable in the Index Portfolio will negatively impact the level of the Autocallable Index and, in turn, the Fund.

The chart below illustrates the payoff profile of a single synthetic least-of Autocallable in the Index Portfolio as a function of the performance of the least-performing Constituent. A Coupon is paid — together with any previously missed Coupons via the memory feature — if the least-performing Constituent is at or above the Coupon Barrier (i.e., at or above 70% of its initial level) on a monthly Observation Date; no Coupon is paid if the least-performing Constituent is below that barrier. Following the Non-Callable Period, the Autocallable is called if the least-performing Constituent is at or above its initial level (100%) on a monthly Observation Date. Contingent principal protection applies against a ‑30% decline in the least-performing Constituent, beyond which, at maturity, losses track the least-performing Constituent.

Illustrative payoff of a single synthetic least-of autocallable income note (before Fund fees and expenses). The dashed line represents the least-performing Constituent. For illustrative purposes only; not indicative of the performance of any Autocallable or of the Fund nor necessarily of actual levels of maturity or coupon barriers.

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Additional Information About Investment Strategies and Related Risks

Portfolio Management and Rebalancing

The Autocallable Index is managed through a systematic process, and the Fund gains exposure to the Autocallable Index through the use of Swap Agreements. The Index Portfolio will be rebalanced weekly, employing a weekly roll mechanism whereby Autocallables that have auto called or matured are replaced with new Autocallables and any Coupons received are reinvested in Autocallables. This systematic approach seeks to benefit from (i) diversification of entry points across market cycles; (ii) minimization of timing risk associated with single-entry investments and (iii) maintaining a consistent exposure to a theoretical portfolio of approximately 52 to 156 synthetic least-of Autocallables. Furthermore, by gaining exposure, via the Autocallable Index, to the total return of a laddered portfolio of Autocallables with staggered entry points, the Fund seeks to benefit from a theoretical diversified portfolio that seeks to (i) smooth capital appreciation over time; (ii) reduce concentration risk in any single market entry point; and (iii) potentially lower overall portfolio volatility.

While the Autocallable Index follows systematic rules for maintenance and replacement, the Adviser actively oversees the Swap Counterparty exposure and creditworthiness, collateral management and optimization, the Fund’s overall portfolio risk characteristics as well as the execution quality and management of Swap Agreements. Because the Fund expects to obtain exposure through Swap Agreements with more than one Swap Counterparty, the Adviser also monitors the allocation of the Fund’s notional swap exposure across Swap Counterparties and manages the onboarding of additional Swap Counterparties as capacity, liquidity and diversification needs arise.

Autocallable Index Methodology

The Autocallable Index is designed to reflect the performance of a theoretical portfolio of synthetic least-of Autocallable notes (the “Autocallables”), the return of which is determined by reference to the least-performing Constituent (SPY, QQQ and IWM) of the Underlying Reference Basket. The Autocallables in the theoretical portfolio follow predetermined terms including a 156-week (3-year) maturity period from issue date, a 52-week (1-year) non-callable period from the issue date, and coupon payments every 4 weeks. Each Autocallable features conditional cash flows on specific monthly Observation Dates, with payments depending on whether the least-performing Constituent is above or below specified thresholds, including a 100% autocallable barrier and 70% principal and coupon barrier percentages, together with a “memory” feature under which unpaid Coupons accumulate and are credited on a later qualifying Observation Date or upon call.

The Autocallable Index provider’s pricing model determines the present value of these synthetic securities accounting for prevailing market conditions and contemplates the reinvestment of cash flows. The Autocallable Index rebalances at preset intervals (weekly), adding one new autocallable security at each rebalance date. To maintain diversification, the Autocallable Index applies concentration limits through an allocation cap that restricts the weight of any individual Autocallable to 5%. Cash from paid Coupons and maturing or redeemed securities is systematically reallocated across the portfolio according to predefined rules. The Autocallable Index is calculated daily, rebalanced weekly and is denominated in U.S. Dollars with the Index base value set at 100.

The Index is composed of a theoretical portfolio of autocallable notes with the following characteristics:

\n\n\n\n\n\n\n\n\n\n\n

	SPECIFICATION	AUTOCALLABLE INDEX
	Reference Asset	Least-performing SPY, QQQ and IWM
	Face Value	100
	Maturity Date	156 weeks from the Issue Date
	Non-Callable Period	52 weeks from the Issue Date
	Coupon Dates	Every 4 weeks from the Issue Date, up to and including the Maturity Date
	Autocallable Barrier	100%
	Principal Barrier Percentage	70%
	Coupon Barrier Percentage	70%
	Memory Feature	Yes — unpaid Coupons credited on a later qualifying observation or upon call

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Additional Information About Investment Strategies and Related Risks

Total Return Swaps — A total return swap is a financial agreement between two parties where one party agrees to make a single payment or periodic payments to the other party based on a fixed or variable interest rate in exchange for a single payment or periodic payments based on the total return of an underlying asset, which includes both the income it generates and any capital gains or losses. Total return swaps also may be used as a means of obtaining exposure in markets where the reference asset is unavailable or it may otherwise be impossible or impracticable for the Fund to own that asset. “Total return” refers to the payment (or receipt) of the total return on the underlying reference asset, which is then exchanged for the receipt (or payment) of an interest rate. To the extent the total return of the underlying asset exceeds or falls short of the offsetting interest rate obligation, one party will receive a payment from or make a payment to the other party, as applicable. Total return swaps provide the Fund with the additional flexibility of gaining exposure to a market or sector index in a potentially more economical way. The use of total return swaps may add leverage to the Fund’s portfolio.

Box Spreads — A Box Spread is an offsetting set of options, which may include Flexible Exchange Options (“FLEX Options”). Box Spreads consist of a synthetic long position coupled with an offsetting synthetic short position through a combination of options contracts on a reference asset at the same expiration date. The synthetic long position consists of (i) buying a call option and (ii) selling a put option, each on the same reference asset and each with the same strike price and expiration date. The synthetic short position consists of (i) buying a put option and (ii) selling a call option, each on the same reference asset and each with the same expiration date as the synthetic long but with a different strike price from the synthetic long position. The difference between the strike prices of the synthetic long position and the synthetic short position determines the expiration value (or value at maturity) of the Box Spread. An important feature of the Box Spread construction process is that it seeks to eliminate market risk tied to price movements associated with the underlying options’ reference asset. Once the Box Spread is initiated, its return from the initiation date through expiration will not change due to price movements in the underlying options’ reference assets. The Fund may purchase Box Spreads on various indices or securities based on risk and return considerations. Box Spreads are expected to have return characteristics similar to cash equivalents. The Fund may also invest in other ETFs which in turn invest principally in Box Spreads.

General Information about FLEX Options

FLEX Options are customizable exchange-traded option contracts guaranteed for settlement by the Options Clearing Corporation (the “OCC”). The OCC guarantees performance by each of the counterparties to the FLEX Options, becoming the “buyer for every seller and the seller for every buyer,” with the goal of protecting clearing members and options traders from counterparty risk. The OCC may make adjustments to FLEX Options for certain significant events, as more fully described in the Fund’s Statement of Additional Information. Although guaranteed for settlement by the OCC, FLEX Options are still subject to counterparty risk with the OCC and subject to the risk that the OCC may fail to perform the settlement of the FLEX Options due to bankruptcy or other adverse reasons. The FLEX Options that the Fund will hold and that reference the SPDR S&P 500 ETF (“SPY”) will give the Fund the right or the obligation to either receive or deliver shares of SPY, or the right or the obligation to either receive or deliver a cash payment on the option expiration date based upon the difference between SPY’s value and a strike price, depending on whether the option is a put or call option and whether the Fund purchases or sells the option. The Fund will purchase call options (giving the Fund the right to receive shares of SPY or a cash payment) and put options (giving the Fund the right to deliver shares of SPY or a cash payment), and may sell (i.e., write) call options (giving the Fund the obligation to deliver shares of SPY or a cash payment) and put options (giving the Fund the obligation to receive shares of SPY or a cash payment) in instances where it is deemed necessary or desirable to construct the Box Spread. In instances where the purchased call and put options are substantially in-the-money and the synthetic long and short positions comprising the Box Spread can effectively be constructed without writing call or put options, the Fund may elect not to write call or put options. The Fund intends to use FLEX Options in constructing Box Spreads. The Fund receives premiums in exchange for the written FLEX Options and pays premiums in exchange for the purchased FLEX Options. The OCC and securities exchanges on which the FLEX Options are listed do not charge ongoing fees to writers or purchasers of the FLEX Options during their life for continuing to hold the option contracts but may charge transaction fees.

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Additional Information About Investment Strategies and Related Risks

Underlying Reference Basket — Constituents

SPY

SPY is an exchange-traded unit investment trust that uses a replication strategy, meaning it invests in as many of the stocks in the S&P 500® Index as is practicable. PDR Services, LLC (“PDR”) serves as SPY’s sponsor. The investment objective of SPY is to seek to provide investment results that, before expenses, correspond generally to the price and yield performance of the S&P 500® Index (the “Index”). See below for a description of the SPY’s principal investment strategies and risks. You can find SPY’s prospectus and other information about the ETF, including the statement of additional information and most recent reports to shareholders, online at “https://www.ssga.com/us/en/intermediary/etfs/state-street-spdr-sp‑500-etf-trust-spy”.

The summary information below regarding the SPY comes from its filings with the SEC. You are urged to refer to the SEC filings made by the SPY and to other publicly available information (e.g., the ETF’s annual reports) to obtain an understanding of the ETF’s business and financial prospects. The following description of the SPY’s principal investment strategies was taken directly from the SPY’s prospectus, dated January 26, 2026 (“SPY” refers to the SPY; other defined terms have been modified and pertain only to this subsection).

SPY seeks to achieve its investment objective by holding a portfolio of the common stocks that are included in the Index (the “Portfolio”), with the weight of each stock in SPY’s Portfolio substantially corresponding to the weight of such stock in the Index. In SPY’s prospectus, the term “Portfolio Securities” refers to the common stocks that are actually held by SPY and make up SPY’s Portfolio, while the term “Index Securities” refers to the common stocks that are included in the Index, as determined by the index provider, S&P Dow Jones Indices LLC (“S&P”). At any time, SPY’s Portfolio will consist of as many of the Index Securities as is practicable. To maintain the correspondence between the composition and weightings of Portfolio Securities and Index Securities, State Street Global Advisors Trust Company (the “Trustee”) or its parent company, State Street Bank and Trust Company (“SSBT”) adjusts SPY’s Portfolio from time to time to conform to periodic changes made by S&P to the identity and/or relative weightings of Index Securities in the Index. SPY’s Trustee or SSBT aggregates certain of these adjustments and makes changes to SPY’s Portfolio at least monthly, or more frequently in the case of significant changes to the Index. SPY may pay transaction costs, such as brokerage commissions, when it buys and sells securities (or “turns over” its Portfolio). Such transaction costs may be higher if there are significant rebalancings of Index Securities in the Index, which may also result in higher taxes when SPY’s units are held in a taxable account. These costs, which are not reflected in SPY’s estimated annual Trust ordinary operating expenses, affect SPY’s performance. During the most recent fiscal year, SPY’s portfolio turnover rate was 3% of the average value of its portfolio. SPY’s portfolio turnover rate does not include securities received or delivered from processing creations or redemptions of SPY’s units. Portfolio turnover will be a function of changes to the Index as well as requirements of SPY’s trust agreement. … Although SPY may fail to own certain Index Securities at any particular time, SPY generally will be substantially invested in Index Securities, which should result in a close correspondence between the performance of the Index and the performance of SPY. … SPY does not hold or trade futures or swaps and is not a commodity pool. The Index includes five hundred (500) selected companies, all of which are listed on national stock exchanges and spans a broad range of major industries. … Since 1968, the Index has been a component of the U.S. Commerce Department’s list of Leading Indicators that track key sectors of the U.S. economy. Current information regarding the market value of the Index is available from market information services. The Index is determined, comprised and calculated without regard to SPY.

As of September 30, 2026, SPY had significant investments in information technology companies.

QQQ

QQQ is an exchange-traded open-end management investment company. Prior to a reclassification on December 19, 2025, the Fund operated as a unit investment trust. QQQ uses a full replication strategy, meaning it invests in all of the stocks in the Nasdaq‑100 Index®. Invesco Capital Management LLC (“Invesco”) serves as QQQ’s investment advisor. The investment objective of QQQ is to seek to track the investment results, before fees and expenses, of the Nasdaq‑100 Index® (the “Index”). See below for a description of QQQ’s principal investment strategies and risks. You can find QQQ’s prospectus and other information about the ETF, online at “https://www.invesco.com/qqq-etf/en/about.html”.

The summary information below regarding QQQ comes from its filings with the SEC. You are urged to refer to the SEC filings made by QQQ and to other publicly available information (e.g., QQQ’s annual reports) to obtain an understanding of QQQ’s business and financial prospects. The following description of QQQ’s principal investment strategies was taken directly from

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Additional Information About Investment Strategies and Related Risks

QQQ’s prospectus, dated December 22, 2025, as revised June 10, 2026 (“QQQ®” refers to QQQ; other defined terms have been modified and pertain only to this subsection).

The investment objective of QQQ® is to seek to track the investment results, before fees and expenses, of the Index. There can be no assurance that this investment objective will be met fully.

Nasdaq, Inc. (“Nasdaq” or the “Index Provider”) compiles, maintains and calculates the Underlying Index, which includes securities of 100 of the largest domestic and international non-financial companies listed on The Nasdaq Stock Market LLC based on market capitalization. QQQ® operates as an index fund and is not actively managed, meaning that it does not seek to outperform the Index. The Fund employs a “full replication” methodology in seeking to track the Index, meaning that the Fund invests in all of the securities comprising the Index in proportion to their weightings in the Index. The Index reflects companies across major industry groups, including computer hardware and software, telecommunications, retail/wholesale trade, and biotechnology. The Index excludes financial companies, including investment companies.

As of October 31, 2025, QQQ had significant investments in information technology companies.

IWM

IWM is an exchange-traded fund that seeks to track the investment results of the Russell 2000® Index (the “Index”), which is a float-adjusted capitalization-weighted index of equity securities issued by the approximately 1,933 smallest issuers in the Russell 3000® Index. IWM measures the performance of the small-capitalization sector of the U.S. equity market, as defined by FTSE Russell.

IWM is a series of an open-end management investment company registered with the SEC under the 1940 Act. IWM uses a replication strategy, meaning it invests in as many of the stocks in the Russell 2000® Index as is practicable. BlackRock Fund Advisors (“BFA”) serves as IWM’s investment adviser. You can find IWM’s prospectus and other information about the ETF, including the statement of additional information and most recent reports to shareholders, online at “https://www.ishares.com/us/products/239710/ishares‑russell‑2000‑etf”.

The summary information below regarding IWM comes from its filings with the SEC. You are urged to refer to the SEC filings made by IWM and to other publicly available information (e.g., the ETF’s annual reports) to obtain an understanding of the ETF’s business and financial prospects. The following description of IWM’s principal investment strategies was taken directly from IWM’s prospectus, dated July 31, 2026 (defined terms have been modified and pertain only to this subsection).

IWM seeks to achieve its investment objective by holding a portfolio of the common stocks that are included in the Index (the “Portfolio”), with the weight of each stock in IWM’s Portfolio substantially corresponding to the weight of such stock in the Index.

As of March 31, 2026, the Index represented approximately 5% of the total market capitalization of the Russell 3000® Index, and a significant portion of the Index is represented by securities of companies in the financials, healthcare and industrials industries or sectors. The components of the Underlying Index are likely to change over time.

To maintain the correspondence between the composition and weightings of Portfolio Securities and Index Securities, BFA adjusts IWM’s Portfolio from time to time to conform to periodic changes made by Russell to the identity and/or relative weightings of Index Securities in the Index. IWM may pay transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in the Annual Fund Operating Expenses or in the Example, affect the IWM’s performance. During the most recent fiscal year, the IWM’s portfolio turnover rate was 18% of the average value of its portfolio.

Although IWM may fail to own certain Index Securities at any particular time, IWM generally will be substantially invested in Index Securities, which should result in a close correspondence between the performance of the Index and the performance of IWM. IWM does not use futures, options on futures or securities options for speculative purposes and is not a commodity pool. The Index is determined, comprised and calculated without regard to IWM.

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Additional Information About Investment Strategies and Related Risks

Changes in 80% policy

The Fund has adopted a non-fundamental operating policy that requires it, under normal circumstances, to invest at least 80% of its net assets (plus borrowings for investment purposes, if any) in U.S. Treasuries, cash, cash equivalents, Box Spreads, box spread ETFs, and unfunded total return swaps that provide exposure to a theoretical portfolio of approximately 52 to 156 Autocallables investments that are linked to the performance of the Autocallable Index. Although this requirement may be changed by the Board of Trustees without shareholder approval, the Fund will notify shareholders in writing at least 60 days prior to any change in its 80% policy.

Non-Principal Investments

Cash Equivalents and Short-Term Investments

The Fund may invest in securities with maturities of less than one year, cash equivalents, it may hold cash or utilize Box Spreads.

Illiquid Securities (Other than Total Return Swaps)

The Fund may invest up to 15% of its net assets in securities and other instruments that are, at the time of investment, illiquid (determined using the Securities and Exchange Commission’s standard applicable to investment companies, i.e., any investment that the Fund reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment). For this purpose, illiquid investments may include, but are not limited to, certain restricted securities (securities the disposition of which is restricted under the federal securities laws), certain securities that may only be resold pursuant to Rule 144A under the Securities Act, and certain repurchase agreements, among others.

Repurchase Agreements and Reverse Repurchase Agreements

As part of its strategy for the temporary investment of cash, the Fund may enter into “repurchase agreements” pertaining to U.S. Government securities with member banks of the Federal Reserve System or primary dealers (as designated by the Federal Reserve Bank of New York) in such securities. A repurchase agreement arises when a Fund purchases a security and simultaneously agrees to resell it to the vendor at an agreed upon future date.

The resale price is greater than the purchase price, reflecting an agreed upon market rate of return that is effective for the period of time a Fund holds the security and that is not related to the coupon rate on the purchased security.

Such agreements generally have maturities of no more than seven days and could be used to permit a Fund to earn interest on assets awaiting long-term investment.

A reverse repurchase agreement is a repurchase agreement in which a Fund is the seller of, rather than the investor in, securities and agrees to repurchase them at an agreed-upon time and price. A reverse repurchase agreement enables a Fund to obtain cash to satisfy unusually heavy redemption requests or for other temporary or emergency purposes without needing to sell portfolio securities, or to earn additional income on portfolio securities, such as Treasury bills or notes.

Use of a reverse repurchase agreement may be preferable to a regular sale and later repurchase of securities because it avoids certain market risks and transaction costs.

Temporary Investments

In response to market, economic, political, or other conditions, the Fund may temporarily invest for defensive purposes that are inconsistent with the Fund’s principal investment strategies. If the Fund does so, different factors could affect the Fund’s performance, and the Fund may not achieve its investment objective.

Risks of Investing in the Fund

This prospectus describes the risks you may face as an investor in the Fund. It is important to keep in mind that generally, investments with a higher potential reward also have a higher risk of losing money. The reverse is also commonly true: the lower the risk, the lower the potential reward. However, as you consider an investment in the Fund, you should also take into account your tolerance for the daily fluctuations of the financial markets and whether you can afford to leave your money in this investment for a long period of time to ride out down periods.

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Additional Information About Investment Strategies and Related Risks

As with any security, there are market and investment risks associated with your investment in the Fund. The value of your investment will fluctuate over time, and it is possible to lose money. Each risk summarized below is considered a “principal risk” of investing in the Fund, regardless of the order in which it appears.

Principal Risks

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Authorized Participant Concentration Risk — Only an Authorized Participant may engage in creation or redemption transactions directly with the Fund, and none of those Authorized Participants is obligated to engage in creation and/or redemption transactions. The Fund has a limited number of institutions that may act as Authorized Participants on an agency basis (i.e., on behalf of other market participants). To the extent that Authorized Participants exit the business or are unable to proceed with creation or redemption orders with respect to the Fund and no other Authorized Participant is able to step forward to create or redeem, Fund Shares may be more likely to trade at a premium or discount to NAV and possibly face trading halts or delisting. Authorized Participant concentration risk may be heightened for ETFs, such as the Fund, that invest in securities or instruments that have lower trading volumes.

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•	Autocallable Structure Risk — The Fund’s returns are correlated to the performance of a theoretical portfolio of Autocallables reflected by the Autocallable Index. Autocallable notes have specific structural features that may be unfamiliar to many investors.

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•	Contingent Income Risk — Coupon payments from the Autocallables are not guaranteed and will not be made if the least-performing Constituent falls below the Coupon Barrier (70%) on Observation Dates. This means the Fund may generate significantly less income than anticipated during market downturns.

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Early Redemption Risk — Autocallables in the Index Portfolio may be called before their scheduled maturity if the least-performing Constituent reaches or exceeds the Autocallable Barrier on Observation Dates. This automatic early redemption could force reinvestment of that portion of the Index Portfolio at lower rates if market yields have declined.

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Barrier Risk — If the Least-performing Constituent falls below the Maturity Barrier (70%) at the maturity of an Autocallable in the Index Portfolio, that portion of the Index Portfolio will be fully exposed to the negative performance of the least-performing Constituent from its initial level. For example, if the least-performing Constituent has declined 45% at maturity of a particular Autocallable, the portion of the Index Portfolio allocated to that note would lose 45% of its value. This conditional protection creates a binary outcome that can result in sudden, significant losses if barriers are breached.

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Basket Dispersion and Correlation Risk — Because the Fund’s downside is tied to the worst-performing asset among three distinct indices (SPY, QQQ, and IWM), the statistical probability of a barrier breach is higher than if the Fund tracked any single index alone. To clarify, a severe localized decline in just one index (e.g., small-cap stocks via IWM) will trigger full principal loss for that portion of the Fund’s portfolio, even if the other two indices perform exceptionally well.

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Box Spread Risk — The Fund may purchase Box Spreads on various indices or securities based on risk and return considerations. If one or more of the individual option positions that comprise a Box Spread are modified or closed separately prior to the option contract’s expiration, then the Box Spread may no longer effectively eliminate risk tied to the underlying reference asset’s price movement. Furthermore, the Box Spread’s value is derived in the market and is in part based on the time until the options comprising the Box Spread expire and the prevailing market interest rates. The Fund’s ability to utilize Box Spreads effectively is dependent on the availability and willingness of other market participants to sell Box Spreads to the Fund at competitive prices. Because Box Spreads involve multiple options transactions, the Fund will incur additional transaction costs when utilizing a box spread strategy which will limit returns when using such a strategy. If the Box Spread does not perform as intended, the Fund could have exposure to the underlying reference asset of the options comprising the Box Spread, which is expected to be the SPY. In such a scenario, the Fund would be subject to the risks of equity securities markets. Equity securities prices fluctuate for several reasons, including changes in investors’ perceptions of the financial condition of an issuer or the general condition of the relevant equity market, such as market volatility, or when political or economic events affecting an issuer occur.

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•	Calculation Methodology Risk — The Autocallable Index employs complex calculation methodologies that may not perform as expected under certain market conditions.

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•	Cash Holdings Risk — To the extent the Fund holds cash positions, the Fund risks achieving lower returns and potential lost opportunities to participate in market appreciation which could negatively impact the Fund’s performance and ability to achieve its investment objective.

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Correlation Risk — The Fund’s return is not likely to match the expected returns of the Index Portfolio or the return of the Autocallable Index for a number of reasons, including — (i) the Fund gains exposure to the Index Portfolio through Swap Agreements rather than direct exposure to the underlying components of the Autocallable Index; (ii) transaction costs, fees, and operational constraints in both the Swap Agreements and the underlying Autocallables may affect returns; (iii) the Index Portfolio may not perform as expected under certain market conditions; and (iv) the Fund’s performance may substantially deviate from investor expectations of how the Index Portfolio should perform in various market scenarios. The Fund’s return may not match the return of the Autocallable Index for a number of reasons, including the payment of periodic distributions to investors, operating expenses, transaction costs, cash management, and differences in calculation methodologies.

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Costs of Buying and Selling Fund Shares — Due to the costs of buying or selling Fund Shares, including brokerage commissions imposed by brokers and bid/ask spreads, frequent trading of Fund Shares may significantly reduce investment results and an investment in Fund Shares may not be advisable for investors who anticipate regularly making small investments.

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Counterparty Risk — The Fund will be subject to credit risk with respect to the counterparties to the derivative contracts (primarily Swap Agreements) entered into by the Fund. The Fund’s exposure to the Index Portfolio is obtained entirely through Swap Agreements with Swap Counterparties. If a Swap Counterparty becomes bankrupt or otherwise fails to perform its obligations, the Fund may experience significant delays in obtaining any recovery, may obtain only a limited recovery, or may obtain no recovery at all. Unlike directly held securities, the Fund’s holdings consist primarily of contractual claims against Swap Counterparties, making the Fund particularly vulnerable to counterparty failure. Even temporary disruptions in a Swap Counterparty’s ability to perform under Swap Agreements could significantly impact Fund performance. The Fund may have substantial exposure to a single Swap Counterparty, amplifying this risk. Certain counterparties, including the Swap Counterparties, may be considered systemically important financial institutions and any deterioration in their financial condition could heighten counterparty risk. The Fund expects to obtain exposure to the Index Portfolio through Swap Agreements with a limited number of counterparties and will likely enter into Swap Agreements related to the Index Portfolio with a limited number of counterparties for the foreseeable future. To the extent that the Fund enters into multiple transactions with a single or a small set of counterparties, it will be subject to increased counterparty risk.

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•	Credit Risk — The Fund’s collateral investments may be subject to credit risk, which is the risk that an issuer or counterparty will fail to pay principal or interest when due.

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Derivatives Risk — Derivatives are instruments, such as swaps, options, futures and forward foreign currency contracts, whose value is derived from that of other assets, rates or indices. Derivatives can be used for hedging (attempting to reduce risk by offsetting one investment position with another) or non-hedging purposes. The use of derivatives for non-hedging purposes may be considered more speculative than other types of investments. The use of derivatives will increase expenses and volatility, and there is no guarantee that a derivatives strategy will work as anticipated. While hedging with derivatives can reduce or eliminate losses, it can also reduce or eliminate gains. In addition, derivative instruments are subject to counterparty risk, meaning that the party with whom the Fund enters into a derivative transaction may experience a significant credit event and/or may be unwilling or unable to make timely settlement payments or otherwise honor its obligations. Changes in the value of a derivative may not correlate perfectly with the underlying asset, rate or index, and the Fund could lose more than the principal amount invested.

The derivatives markets are subject to various global regulations, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. For example, in October 2020, the SEC adopted Rule 18f‑4 under the 1940 Act, which applies to the Fund’s use of derivative investments and certain financing transactions (e.g., reverse repurchase agreements). Among other things, Rule 18f‑4 requires funds that invest in derivative instruments beyond a

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Additional Information About Investment Strategies and Related Risks

specified limited amount to apply a value-at-risk based limit to their use of certain derivative instruments and financing transactions and to adopt and implement a derivatives risk management program. In connection with compliance with Rule 18f‑4, funds are no longer required to comply with the asset segregation framework arising from prior SEC guidance for covering certain derivative instruments and related transactions.

These and other rules and regulations could, among other things, further restrict a Fund’s ability to engage in, or increase the cost to a Fund of derivatives transactions, for example, by making some types of derivatives no longer available to the Fund or otherwise limiting liquidity. This may result in changes to a Fund’s principal investment strategies and could adversely affect a Fund’s performance and its ability to achieve its investment objective.

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Equity Securities Risk — The securities markets are volatile. The Fund’s exposure to the least-performing Constituent subjects it to risks associated with equity markets. The value of the least-performing Constituent may fluctuate, sometimes rapidly and unpredictably, due to factors affecting the U.S. equity markets generally or particular segments of the market. If the market prices of the securities to which the least-performing Constituent is exposed decline, the value of your investment in the Fund will decline.

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FLEX Options Risk — Trading FLEX Options involves risks different from, and possibly greater than, the risks associated with investing directly in securities or in other types of options. FLEX Options, like other listed options, are traded on the U.S. options markets and are issued by OCC. However, unlike other options, the terms of FLEX Options are not all standardized. When a FLEX Option is purchased and sold in an opening transaction, the parties to the transaction have the flexibility, within limitations set forth in the rules of the options market on which the transaction occurs, to fix certain of the option’s terms. The flexibility to fix certain terms is what makes FLEX Options different from other types of options. Because many of the terms of FLEX Options are not standardized, it is less likely that there will be an active secondary market in which holders and writers of such options will be able to close out their positions by offsetting sales and purchases. Because FLEX Options have variable terms that are fixed by the parties, there are no pre-established series of FLEX Options. Rather, any different series of FLEX Options may be created and outstanding at any given time as a result of the various designations of variable terms that are made in different transactions. Secondary trading interest in FLEX Options may therefore be spread over a larger number of series than the trading interest in other options, the trading interest in any particular series of FLEX Options may be very limited, the secondary markets in FLEX Options may be less deep, liquid and continuous than the markets in other options on the same underlying interests, and the premiums for FLEX Options may not correlate with premiums for such other options. In the event that trading in the FLEX Options is limited or absent, the value of the Fund’s FLEX Options may decrease. In a less liquid market for the FLEX Options, liquidating the FLEX Options may require the payment of a premium (for written FLEX Options) or acceptance of a discounted price (for purchased FLEX Options) and may take longer to complete. A less liquid trading market may adversely impact the value of the FLEX Options and Fund Shares and result in the Fund being unable to achieve its investment objective. Less liquidity in the trading of the Fund’s FLEX Options could have an impact on the prices paid or received by the Fund for the FLEX Options in connection with creations and redemptions of the Fund Shares. Depending on the nature of this impact to pricing, the Fund may be forced to pay more for redemptions (or receive less for creations) than the price at which it currently values the FLEX Options. Such overpayment or under collection may impact the value of the Fund and whether the Fund can satisfy its investment objective. Additionally, in a less liquid market for the FLEX Options, the liquidation of a large number of options may more significantly impact the price. A less liquid trading market may adversely impact the value of the FLEX Options and the value of your investment. The trading in FLEX Options may be less deep and liquid than the market for certain other exchange-traded options, non-customized options or other securities. The Fund also is subject to the risk that the OCC will become insolvent or otherwise be unable to meet its obligations, which could cause the Fund to suffer losses which may be significant.

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•	Interest Rate Risk — The value of the Fund’s fixed-income investments may be affected by changes in interest rates. When interest rates rise, the value of fixed-income investments generally falls.

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Although the Subsidiary may be considered similar to investment companies, it is not registered under the 1940 Act and, unless otherwise noted in the Fund’s Prospectus and SAI, is not subject to all of the investor protections of the 1940 Act and other U.S. regulations. The Board of Trustees, however, has oversight responsibility for the investment activities of the Fund, including its investment in its respective subsidiary. In addition, the Fund is the sole shareholder of its respective Subsidiary, and it is not currently expected that shares of a Subsidiary will be sold or offered to other investors. Changes in the laws of the United States and/or the Cayman Islands could result in the inability of the Fund and/or a Subsidiary to operate as described in the Fund’s Prospectus and SAI and could negatively affect the Fund and its shareholders.

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•	Liquidity Risk — Liquidity risk exists when particular investments are difficult to purchase or sell. The Fund’s investments in illiquid securities may reduce the returns of the Fund because it may be unable to sell the illiquid securities at an advantageous time or price.

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•	Market Risk — The risk that the securities markets will increase or decrease in value is considered market risk and applies to any security, including those held by the Index Portfolio.

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•	New Fund Risk — The Fund is a recently organized investment company with a limited operating history. As a result, prospective investors have a limited track record or history on which to base their investment decision.

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•	Other Investment Companies Risk — The Fund may invest in the securities of other investment companies to the extent that such investments are consistent with the Fund’s investment objectives and permissible under the 1940 Act.

Under one provision of the 1940 Act, the Fund may not acquire the securities of other investment companies if, as a result, (i) more than 10% of the Fund’s total assets would be invested in securities of other investment companies, (ii) such purchase would result in more than 3% of the total outstanding voting securities of any one investment

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Additional Information About Investment Strategies and Related Risks

company being held by the Fund or (iii) more than 5% of the Fund’s total assets would be invested in any one investment company. In some instances, the Fund may invest in an investment company in excess of these limits. For example, the Fund may invest in other registered investment companies, such as mutual funds, closed-end funds and exchange-traded funds (“ETFs”), including affiliated funds, and in business development companies in excess of the statutory limits imposed by the 1940 Act in reliance on Rule 12d1‑4 under the 1940 Act. These investments would be subject to the applicable conditions of Rule 12d1‑4, which in part would affect or otherwise impose certain limits on the investments and operations of the underlying fund. The Fund, as a holder of the securities of other investment companies, will bear its pro rata portion of the other investment companies’ expenses, including advisory fees. These expenses will be in addition to the direct expenses incurred by the Fund. In the event the Fund invests in another affiliated fund (the “Acquired Fund”), the portion of the Fund’s Investment Management Fee equal to the advisory fee payable to the Acquired Fund (based on average daily net assets invested) is waived.

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Swap Agreement Risk — Swap agreements are a type of derivative instrument that subjects the Fund to counterparty credit, liquidity, and correlation risks, including that: (i) the Fund may not be able to enter into replacement swap agreements in the event a current swap is terminated; (ii) unfunded swap agreements may involve greater leverage risks than funded swaps; (iii) the swap agreement may not reflect the performance of the Autocallable Index or the least-performing Constituent Basket as expected due to differences in calculation methods or expenses; and (iv) during market disruptions, the counterparty may be able to terminate the swap agreement and the Fund may be unable to enter into new swap agreements or adjust existing positions at favorable prices. The terms of a swap agreement between the Fund and its counterparty may permit the counterparty to voluntarily close out the transaction with the Fund or terminate if certain events occur with respect to the Fund. In that event, the Fund may be unable to enter into another swap agreement or invest in other derivatives to achieve the desired exposure consistent with the Fund’s investment objective. This, in turn, may prevent the Fund from achieving its investment objective. There can be no assurance that a liquid secondary market will exist for any particular derivative instrument at any particular time, including for those derivative instruments that were originally categorized as liquid at the time they were acquired by the Fund. In volatile markets, the Fund may not be able to close out a position without incurring a significant amount of loss. Swap agreements generally are not assignable except by agreement between the parties, and a counterparty typically has no obligation to permit assignments. Even if the Fund’s counterparty agrees to early termination of a swap agreement at any time, doing so may subject the Fund to certain early termination charges. To the extent that the Fund enters into multiple transactions with a single or a small set of counterparties, it will be subject to increased counterparty risk.

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Swap Agreement Termination Risk — A Swap Counterparty may be entitled to terminate the Swap Agreement at its then current market value upon the occurrence of certain extraordinary market events or at its discretion upon notice to the Fund. Under such circumstances, if the Adviser is unable to enter into new Swap Agreements with a suitable Swap Counterparty, the Adviser may recommend to the Board of Trustees to immediately liquidate the Fund. A liquidation can be initiated by the Board of Trustees without a shareholder vote. While shareholder interests will be the paramount consideration in a liquidation under such circumstances, the timing of the liquidation may not be favorable to certain individual shareholders.

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•	Tax Risk — The Fund intends to elect and to qualify each year to be treated as a regulated investment company (“RIC”) under Subchapter M of the Code. To qualify and maintain its status as a RIC, the Fund must derive at least 90% of its

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Additional Information About Investment Strategies and Related Risks

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gross income each year from “qualifying income,” meet certain diversification tests at the end of each quarter and meet an annual distribution test. For purposes of the qualifying income requirement, the treatment of the swaps and other derivatives that provide exposure to the Autocallables is not entirely clear, and thus whether the income and gain therefrom is qualifying income is uncertain. If the Fund were to treat income or gain from particular instruments linked to the Autocallables as qualifying income, an adverse determination or future guidance by the Internal Revenue Service with respect to the treatment of income or gain from those investments may adversely affect the Fund’s ability to qualify as a RIC. For purposes of the diversification test, the identification of the issuer (or, in some cases, issuers) of a particular Fund investment can depend on the terms and conditions of that investment. In particular, there is no published Internal Revenue Service guidance or case law on how to determine the “issuer” of certain derivatives that the Fund will enter into. An adverse determination or future guidance by the Internal Revenue Service with respect to issuer identification for the Fund’s investments may adversely affect the Fund’s ability to qualify as a RIC. If the Fund does not qualify as a RIC for any taxable year and certain relief provisions are not available, the Fund’s taxable income will be subject to tax at the Fund level and to a further tax at the shareholder level when such income is distributed.

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Trading Issues Risk — Trading in Fund Shares on the Exchange may be halted due to market conditions or for reasons that, in the view of the Exchange, make trading in shares inadvisable. In addition, trading in Fund Shares on the Exchange is subject to trading halts caused by extraordinary market volatility pursuant to the Exchange’s “circuit breaker” rules. There can be no assurance that the requirements of the Exchange necessary to maintain the listing of the Fund will continue to be met or will remain unchanged. The Fund may have difficulty maintaining its listing on the Exchange in the event the Fund’s assets are small, the Fund does not have enough shareholders, or if the Fund is unable to proceed with creation and/or redemption orders.

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The following are non-principal risks that generally apply to the Fund:

Market Events Risk. Economies and financial markets throughout the world are increasingly interconnected. Economic, financial or geopolitical events, trading and tariff arrangements (including trade or diplomatic disputes resulting in the imposition of economic sanctions or the threat of new or modified sanctions), terrorism, wars, cybersecurity events, natural or environmental disasters and other circumstances in one country or region could have profound impacts on global economies or markets. Widespread disease and virus epidemics, such as the coronavirus outbreak, could likewise be highly disruptive, adversely affecting individual companies, sectors, industries, markets, currencies, interest and inflation rates, credit ratings, investor sentiment, and other factors affecting the value of the Fund’s investments. As a result, whether or not the Fund invests in securities of issuers located in or with significant exposure to the countries directly affected, the value and liquidity of the Fund’s investments may be negatively affected.

Policy and legislative changes in the United States and in other countries may impact the financial markets. The impact of these changes on the markets, and the practical implications for market participants, may not be fully known for some time.

Cybersecurity Risk. Investment companies, such as the Fund, and their service providers are exposed to operational and information security risks resulting from cyberattacks, which may result in financial losses to the Fund and its shareholders. Cyber-attacks include, among other behaviors, stealing or corrupting data maintained online or digitally, denial of service attacks on websites, “ransomware” that renders systems inoperable until ransom is paid, the unauthorized release of confidential information, or various other forms of cybersecurity breaches. Cyber-attacks affecting the Fund, Calamos Advisors,

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Additional Information About Investment Strategies and Related Risks

custodian, transfer agent, distributor, market maker, authorized participants, administrator, intermediaries, trading counterparties, and other third-party service providers may adversely impact the Fund or the companies in which the Fund invests, causing the Fund’s investments to lose value or to prevent a shareholder redemption or purchase from clearing in a timely manner.

Investment Management Risk. Whether the Fund achieves its investment objective(s) is significantly impacted by whether the Adviser is able to choose suitable investments for the Fund.

Market Disruption Risk. Certain events have a disruptive effect on securities markets, including but not limited to, terrorist attacks, war and other geopolitical events or catastrophes. The Adviser cannot predict the effect of similar events in the future on the U.S. or foreign economies. Certain securities such as high yield and equity securities tend to be impacted more by these events than other types of securities in terms of price and volatility.

Operational Risk. The Fund is subject to risks arising from various operational factors, including, but not limited to, human error, processing and communication errors, errors of the Fund’s service providers, counterparties or other third-parties, failed or inadequate processes and technology or systems failures. The Fund relies on third-parties for a range of services, including custody. Any delay or failure relating to engaging or maintaining such service providers may affect the Fund’s ability to meet its investment objective. Although the Fund and the Adviser seek to reduce these operational risks through controls and procedures, there is no way to completely protect against such risks.

Recent Market Events. Since the 2008 financial crisis, financial markets throughout the world have experienced increased periods of volatility, depressed valuations, decreased liquidity and heightened uncertainty and turmoil. This turmoil resulted in unusual and extreme volatility in the equity and debt markets, in the prices of individual securities and in the world economy. Events that have contributed to these market conditions include, but are not limited to, major cybersecurity events, geopolitical events (such as wars, terror attacks, natural or environmental disasters, country instability, and public health emergencies), trade disputes, tariffs and other restrictions on trade or economic sanctions, measures to address budget deficits, downgrading of sovereign debt, significant changes in oil and commodity prices, dramatic changes in currency exchange rates, and public sentiment. In addition, many governments and quasi-governmental entities throughout the world have responded to the turmoil with a variety of significant fiscal and monetary policy changes, including, but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates.

Russia’s military invasion of Ukraine has resulted in sanctions and market disruptions, including declines in regional and global stock markets, unusual volatility in global commodity markets and significant devaluations of Russian currency. In addition, the Iranian conflict that commenced in February 2026 may result in similar, and potentially more severe, disruptions. Escalation of hostilities in the Middle East region could disrupt energy production or transportation, including through key shipping routes, which may lead to increased volatility in energy and other commodity prices. The extent and duration of these conflicts are impossible to predict but could continue to be significant.

The UK left the EU on January 31, 2020 (commonly known as “Brexit”). The UK and the EU entered into a Trade and Cooperation Agreement that sets out the agreement for certain parts of the future relationship from January 1, 2021, but uncertainty remains in certain areas regarding the future UK-EU relationship.

From January 1, 2021, EU laws ceased to apply in the UK, with many being assimilated into UK law. The UK government has enacted legislation to repeal, replace or make substantial amendments to these laws, with a view to them being replaced by purely domestic legislation. The process of revoking EU laws and replacing them with bespoke UK laws has already begun, creating unpredictable consequences for financial markets and investments. Brexit could significantly impact the UK, European, and global macroeconomic conditions, leading to prolonged political, legal, regulatory, tax, and economic uncertainty. This uncertainty may affect opportunities, pricing, availability, and cost of financing, regulation, values, or exit opportunities of companies or assets based in, doing business with, or having significant relationships in the UK or EU.

In addition, policy and legislative changes in the United States and in other countries are changing many aspects of financial regulation. The impact of these changes on the markets, and the practical implications for market participants, may not be fully known for some time. Widespread disease and virus epidemics and pandemics, such as the coronavirus outbreak, could

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Additional Information About Investment Strategies and Related Risks

likewise be highly disruptive, adversely affecting individual companies, sectors, industries, markets, currencies, interest and inflation rates, credit ratings, investor sentiment, and other factors affecting the value of the Fund’s investments.

Recent technological developments in, and the increasingly widespread use of, artificial intelligence, including machine learning technology and generative artificial intelligence (“AI”), may pose risks to the Fund. For instance, the economy may be significantly impacted by the advanced development and increased regulation of AI. As AI is used more widely, the profitability and growth of the Fund holdings may be impacted, which could significantly impact the overall performance of the Fund. The legal and regulatory frameworks within which AI operates continue to rapidly evolve, and it is not possible to predict the full extent of current or future risks related thereto.

Portfolio security holdings disclosure

A description of the Fund’s policies and procedures in connection with the disclosure of portfolio security holdings of the Fund are available in the SAI and on the Fund’s website, www.calamos.com.

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Fund Facts

Who manages the Fund?

Investment Adviser

The Fund is advised by Calamos Advisors LLC (“Calamos Advisors” or the “Adviser”), 2020 Calamos Court, Naperville, Illinois 60563. Calamos Advisors, an investment adviser registered with the SEC effective May 29, 1987, is a wholly owned subsidiary of Calamos Investments LLC (“CILLC”). CILLC’s assets under management as of December 31, 2025, were $47 billion ($44 billion of which represented Calamos Advisors’ assets under management).

As of June 23, 2026, approximately 78% of the outstanding interests of CILLC was owned by Calamos Partners LLC (“CPL”), 22% by Calamos Asset Management, Inc. (“CAM”), and 0.04% by Calamos Equity Partners LLC (“CEP”). CPL is the sole manager of CILLC. John P. Calamos, Sr. controls CILLC and the Adviser through his controlling interest in both CPL and CAM through the John P. Calamos QTIP Trust, an irrevocable trust with Mr. Calamos as sole trustee and investment adviser. John S. Koudounis is the other owner of both CAM and CPL. CEP is owned by John S. Koudounis and Daniel L. Dufresne.

Subject to the overall authority of the Board of Trustees, Calamos Advisors provides continuous investment supervision and management to the Fund under a management agreement and also furnishes office space, equipment and management personnel. For these services, the Fund pays Calamos Advisors a fee based on its average daily net assets, which is accrued daily and paid on a monthly basis. The Fund will pay fees (before any reimbursement) under the management agreement in the following amounts as a percentage of its average net assets:

\n\n\n

	ETF	FEES
	Calamos Least-Of Autocallable Income ETF	0.74	%

Out of this management fee, Calamos Advisors pays substantially all expenses of the Fund, including the cost of transfer agency, custody, fund administration, legal, audit and other service and license fees, except for distribution and service fees payable pursuant to a Rule 12b‑1 plan, if any, acquired fund fees and expenses, brokerage commissions and other expenses connected with the execution of portfolio transactions, taxes, interest, and extraordinary expenses.

At a meeting held on September 29, 2026, the Board of Trustees approved the Investment Management Agreement for the Fund. A discussion regarding the basis for the Board’s approval of the Investment Management Agreement on behalf of the Fund will be included in the first shareholder report that covers the period in which the Fund commences operations.

Portfolio Managers

Shaheen Iqubal. Shaheen Iqubal joined Calamos Advisors in 2017 as Senior Vice President, Head of Quantitative Investments, Co-Head of Risk. In February 2025, he was named Co-Portfolio Manager, and prior to that from January 2024 through January 2025 served as Associate Portfolio Manager. Shaheen is responsible for oversight of our quantitative investment and risk management teams. Prior to joining the firm, Shaheen was executive director and senior quantitative analyst in the applied research group at UBS Asset Management.

Jordan Rosenfeld. Jordan Rosenfeld joined Calamos Advisors in April 2025 and is a Co-Portfolio Manager. Between June 2018 to March 2025, Mr. Rosenfeld was a Senior Director and Portfolio Manager at Milliman, where he was responsible for managing derivatives strategies in ETFs, mutual funds, and unit investment trusts. Previously, he was a Trader at Gelber Group from January 2016 to December 2017.

The Fund’s SAI provides additional information about each portfolio manager, including other accounts they manage, their ownership in the Calamos Family of Funds and their compensation.

Management Approach

Calamos Advisors employs a “team of teams” approach to portfolio management, led by the Global Chief Investment Officer (“CIO”) and our CIO team consisting of 5 Co-CIOs with specialized areas of investment expertise. The Global CIO and Co-CIO team are responsible for oversight of investment team resources, investment processes, performance and risk. As heads of investment verticals, Co-CIOs manage investment team members and, along with Co-Portfolio Managers and Associate Portfolio Managers, have day-to-day portfolio oversight and construction responsibilities of their respective investment

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strategies. While investment research professionals within each Co-CIO’s team are assigned specific strategy responsibilities, they also provide support to other investment team verticals, creating deeper insights across a wider range of investment strategies. The combination of specialized investment teams with cross-team collaboration results in what we call our team of teams approach.

This team of teams approach is further reflected in the composition of Calamos Advisors’ Investment Committee, made up of the Global CIO, the Co-CIO team, and the Global Head of Trading. Other members of the investment team participate in Investment Committee meetings in connection with specific investment related issues or topics as deemed appropriate.

The structure and composition of the Investment Committee results in a number of benefits, as it:

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Leads to broader perspective on investment decisions: multiple viewpoints and areas of expertise feed into consensus;

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Promotes collaboration between teams; and

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Functions as a think tank with the goal of identifying ways to outperform the market on a risk-adjusted basis.

The objectives of the Investment Committee are to:

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Form the firm’s top-down macro view, market direction, asset allocation, and sector/country positioning.

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Establish firm-wide secular and cyclical themes for review.

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Review firm-wide and portfolio risk metrics, recommending changes where appropriate.

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Review firm-wide, portfolio and individual security liquidity constraints.

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Evaluate firm-wide and portfolio investment performance.

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Evaluate firm-wide and portfolio hedging policies and execution.

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Evaluate enhancements to the overall investment process.

How to Buy and Sell Shares

Fund Shares are listed for secondary trading on the Exchange under the symbol CAYN and individual Fund Shares may only be purchased and sold in the secondary market through a broker-dealer. The Exchange and secondary markets are closed on weekends and also are generally closed on the following holidays: New Year’s Day, Dr. Martin Luther King, Jr. Day, Presidents’ Day, Good Friday, Memorial Day (observed), Juneteenth National Independence Day, Independence Day, Labor Day, Thanksgiving Day and Christmas Day. The Exchange may close early on the business day before certain holidays and on the day after Thanksgiving Day. Exchange holiday schedules are subject to change without notice. If you buy or sell Fund Shares in the secondary market, you will pay the secondary market price for Fund Shares. In addition, you may incur customary brokerage commissions and charges and may pay some or all of the spread between the bid and the offered price in the secondary market on each leg of a round trip (purchase and sale) transaction.

The trading prices of Fund Shares will fluctuate continuously throughout trading hours based on market supply and demand rather than the relevant Fund’s net asset value, which is calculated at the end of each business day.

Fund Shares will trade on the Exchange at prices that may be above (i.e., at a premium) or below (i.e., at a discount), to varying degrees, the daily net asset value of Fund Shares. The trading prices of Fund Shares may deviate significantly from the Fund’s net asset value during periods of market volatility. Given, however, that Fund Shares can be issued and redeemed daily in Creation Units, the Adviser believes that large discounts and premiums to net asset value should not be sustained over long periods.

Authorized Participants may acquire shares directly from the Fund, and Authorized Participants may tender their shares for redemption directly to the Fund, at NAV per share only in Creation Units. Purchases and redemptions directly with the Fund must follow the Fund’s procedures, which are described in the SAI.

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The Fund may liquidate and terminate at any time without shareholder approval.

Book Entry

Fund Shares are held in book-entry form, which means that no stock certificates are issued. The Depository Trust Company (“DTC”) or its nominee is the record owner of all outstanding Shares of the Fund and is recognized as the owner of all Shares for all purposes.

Investors owning Fund Shares are beneficial owners as shown on the records of DTC or its participants. DTC serves as the securities depository for all Fund Shares. Participants in DTC include securities brokers and dealers, banks, trust companies, clearing corporations and other institutions that directly or indirectly maintain a custodial relationship with DTC. As a beneficial owner of Fund Shares, you are not entitled to receive physical delivery of stock certificates or to have Fund Shares registered in your name, and you are not considered a registered owner of Fund Shares. Therefore, to exercise any right as an owner of Fund Shares, you must rely upon the procedures of DTC and its participants. These procedures are the same as those that apply to any other securities that you hold in book entry or “street name” form.

Fund Share Trading Prices

The trading prices of Shares of the Fund on the Exchange may differ from the Fund’s daily NAV. Market forces of supply and demand, economic conditions and other factors may affect the trading prices of Shares of the Fund.

The approximate value of Shares of the Fund, an amount representing on a per share basis the sum of the current market price of the cash or securities, as applicable, accepted by the Fund in exchange for Shares of the Fund and an estimated cash component, if any, is disseminated every 15 seconds throughout the trading day through the facilities of the Consolidated Tape Association. This approximate value should not be viewed as a “real-time” update of the NAV per Share of the Fund because the approximate value may not be calculated in the same manner as the NAV, which is computed once a day, generally at the end of the business day. The Fund is not involved in, or responsible for, the calculation or dissemination of the approximate value of the Fund Shares and the Fund does not make any warranty as to its accuracy.

Frequent Purchases and Redemptions of Fund Shares

Shares of the Fund may be purchased and redeemed directly from the Fund only in Creation Units by Authorized Participants. The vast majority of trading in Shares of the Fund occurs on the secondary market and does not involve the Fund directly. In-kind purchases and redemptions of Creation Units by Authorized Participants and cash trades on the secondary market are unlikely to cause many of the harmful effects of frequent purchases and/or redemptions of Fund Shares. Cash purchases and/or redemptions of Creation Units, however, can result in disruption of portfolio management, dilution to the Fund and increased transaction costs, which could negatively impact the Fund’s ability to achieve its investment objective, and may lead to the realization of capital gains. These consequences may increase as the frequency of cash purchases and redemptions of Creation Units by Authorized Participants increases. However, direct trading by Authorized Participants is critical to ensuring that Fund Shares trade at or close to NAV.

The Fund imposes no restrictions on the frequency of purchases and redemptions (“market timing”). To minimize these potential consequences of frequent purchases and redemptions of Fund Shares, the Fund employs fair valuation pricing and imposes transaction fees on purchases and redemptions of Creation Units to cover the custodial and other costs the Fund incurs in effecting trades. In addition, the Adviser monitors trades by Authorized Participants for patterns of abusive trading and the Fund reserves the right to not accept orders from Authorized Participants that the Adviser has determined may be disruptive to the management of the Fund, or otherwise are not in the best interests of the Fund. For these reasons, the Board has not adopted policies and procedures with respect to frequent purchases and redemptions of Fund Shares. The Trust’s policies and procedures regarding frequent purchases and redemptions may be modified by the Board of Trustees at any time.

The Trust’s policies and procedures prohibit the practice of any officer or employee of the Trust, a Trust investment adviser (including any sub-adviser), the distributor, custodian, or transfer agent placing orders to purchase or redeem shares of a series of the Trust after the designated time as of which the Fund calculates its NAV (i.e., “late trading”).

Distribution and Service Plan

The Fund has adopted a distribution and service plan (“Plan”) pursuant to Rule 12b‑1 under the 1940 Act. Under the Plan, the Fund is authorized to pay distribution fees to the Distributor and other firms that provide distribution and shareholder services

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(“Service Providers”). If a Service Provider provides such services, the Fund may pay fees at an annual rate not to exceed 0.25% of average daily net assets, pursuant to Rule 12b‑1 under the 1940 Act.

No distribution or service fees are currently paid by the Fund, however, and there are no current plans to impose these fees. In the event Rule 12b‑1 fees are charged, over time they would increase the cost of an investment in the Fund because they would be paid on an ongoing basis.

Fund Website and Disclosure of Portfolio Holdings

The Trust maintains a website for the Fund at www.calamos.com. Among other things, this website includes this Prospectus and the SAI, and will include the Fund’s holdings, the Fund’s last annual and semi-annual reports (when available), pricing information about Fund Shares trading on the Exchange, daily NAV calculations and a historical comparison of the trading prices to NAV.

Each day the Fund is open for business, the Trust publicly disseminates the Fund’s full portfolio holdings as of the close of the previous day through its website at www.calamos.com. A description of the Trust’s policies and procedures with respect to the disclosure of the Fund’s portfolio holdings is available in the Fund’s SAI.

Dividends, Other Distributions and Taxes

Fund Distributions

The Fund intends to make distributions monthly and distribute long-term capital gains, if any, at least annually.

Distributions in cash may be reinvested automatically in additional whole Fund Shares only if the broker through whom you purchased Fund Shares makes such option available. The Fund realizes capital gains or losses whenever it sells securities. Net long-term capital gains are distributed to shareholders as “capital gain dividends.”

Brokers may make available to their customers who own Fund Shares the DTC book-entry dividend reinvestment service. To determine whether the dividend reinvestment service is available and whether there is a commission or other charge for using this service, consult your broker. Brokers may require Fund shareholders to adhere to specific procedures and timetables. If this service is available and used, dividend distributions of both income and net realized gains will be automatically reinvested in additional whole Fund Shares of the Fund purchased in the secondary market. Without this service, investors would receive their distributions in cash.

Taxes

As with any investment, you should consider how your investment in Fund Shares will be taxed. The tax information in this prospectus is provided only as general information. This section is current as of the date of this prospectus. Tax laws and interpretations change frequently, and these summaries do not describe all of the tax consequences to all taxpayers. For example, these summaries generally do not describe your situation if you are a corporation, a non-U.S. person, a broker-dealer, or other investor with special circumstances. However, with respect to certain tax issues, the summaries describe the general tax treatment of certain distributions made to corporations and non-U.S. persons. In addition, this section does not describe your state, local or non-U.S. tax consequences. You should consult your own tax advisor about the tax consequences of an investment in Fund Shares.

Fund distributions to you and the sale or redemption of your Fund Shares will have tax consequences to you. Such consequences may be different if you hold your Fund Shares through a tax-exempt entity or tax-advantaged retirement account, such as an individual retirement account or 401(k) plan.

The Fund intends to elect to be treated, and intends to qualify each year, as a regulated investment company (a “RIC”) under the Code. As a RIC, the Fund is generally not subject to corporate-level U.S. federal income tax on any net ordinary income or capital gains that are timely distributed to shareholders. However, the Fund’s failure to qualify as a RIC or to meet minimum distribution requirements would result (if certain relief provisions were not available) in corporate-level taxation and, consequently, a reduction in amounts available for distribution to shareholders.

For purposes of the qualifying income test, the treatment of derivatives that provide exposure to the Autocallable Index is not entirely clear, and thus whether the income and gain therefrom is qualifying income is uncertain. An adverse determination or

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future guidance by the Internal Revenue Service with respect to the treatment of income or gain from those investments may adversely affect the Fund’s ability to qualify as a regulated investment company. See discussion under heading “Tax Risk.”

For purposes of the diversification tests, the identification of the issuer (or, in some cases, issuers) of a particular investment can depend on the terms and conditions of such investment. In particular, there is no published Internal Revenue Service guidance or case law on how to determine the “issuer” of various derivatives that the Fund may enter into. Therefore, there is a risk that the Fund will not meet the Code’s diversification requirements and will not qualify, or will be disqualified, as a RIC.

Taxes on Distributions

Distributions by the Fund generally are taxable to you as ordinary income or capital gains. Distributions are subject to federal income tax, whether received in cash or reinvested in additional Fund shares or shares of another fund, and may be subject to state or local taxes. Distributions of the Fund’s “investment company taxable income” generally will be taxable as ordinary income to the extent of the Fund’s current or accumulated earnings and profits. Notwithstanding the foregoing, distributions that are attributable to “qualified dividends” received by the Fund may be eligible to be taxed at long-term capital gains rates, as long as the Fund and the shareholder meet certain holding period requirements. It is not anticipated that the Fund will have qualified dividend income.

Distributions of the Fund’s net capital gain that are properly reported by the Fund as “capital gain dividends” will generally be taxable to you as long-term capital gains, currently at a maximum rate of 20%, regardless of your holding period in the Fund Shares. Distributions in excess of the Fund’s current and accumulated earnings and profits first will reduce your adjusted tax basis in your Fund Shares and, after the adjusted basis is reduced to zero, will constitute capital gain. Such capital gain will be long-term capital gain and thus, will be taxed at a maximum rate of 20%, if the distributions are attributable to Fund Shares that you have held for more than one year.

Certain non-corporate taxpayers will also be subject to a 3.8% U.S. federal Medicare contribution tax with respect to the lesser of (1) their “net investment income” or (2) the excess of their “modified adjusted gross income” over a threshold amount ($200,000 for single taxpayers and $250,000 for taxpayers who are married and filing jointly).

Corporate shareholders of the Fund are generally eligible for a dividends-received deduction with respect to ordinary income dividends (but not capital gain dividends) properly designated as eligible for such deduction by the Fund, as long as the Fund and the corporate shareholder meet certain holding period and other requirements. It is not anticipated that the Fund will make distributions eligible for the dividend-received deduction.

Under a dividend reinvestment service, you may have the option to have all cash distributions automatically reinvested in additional Fund Shares. Any distributions reinvested under such a service will nevertheless be taxable to you as described above.

You will have an adjusted basis in the additional Fund Shares purchased through such a reinvestment service equal to the amount of the reinvested distribution plus the amount of any fees charged for the transaction. The additional Fund Shares will have a holding period commencing on the day following the day on which they are credited to your account.

A distribution will reduce the Fund’s NAV per Share and generally will be taxable to you as ordinary income or capital gain even if it is paid from income or gains earned by the Fund before you invested in the Fund. From an investment standpoint, such a distribution constitutes a return of capital. However, from a tax standpoint, it constitutes taxable income. In general, distributions are subject to federal income tax as of the date of payment. However, distributions paid in January will be treated as paid on December 31 of the prior year if they were declared and payable to shareholders of record on a date in October, November or December of the prior year.

The Fund’s transactions in derivatives (including the swaps described above), as well as any of its hedging, short sale, securities loan or similar transactions may be subject to one or more special tax rules. These rules may affect whether gains and losses recognized by the Fund are treated as ordinary or capital, accelerate the recognition of income or gains to the Fund, defer losses to the Fund, and cause adjustments in the holding periods of the Fund’s securities, thereby affecting whether capital gains and losses are treated as short-term or long-term. These rules could therefore affect the amount, timing and/or character of distributions to shareholders and thus taxes payable by shareholders.

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You may be subject to federal back-up withholding tax, if you do not provide the Fund with a taxpayer identification number (for an individual, a social security number) and make other required certifications, or the Internal Revenue Service informs the Fund that your tax identification number is incorrect. Backup withholding is not an additional tax. You may claim the amount withheld as a credit on your federal income tax return, provided you furnish the appropriate information to the Internal Revenue Service.

Taxes When Fund Shares are Sold

Any capital gain or loss realized upon a sale of Fund Shares is generally treated as long-term capital gain or loss if you have held the Fund Shares for more than one year and as short-term capital gain or loss if you have held the Fund Shares for one year or less. Long-term capital gain is taxed to individuals at reduced rates relative to short-term capital gain. The ability to deduct capital losses realized on a sale of Fund Shares may be limited.

Taxes on Purchase and Redemption of Creation Units

An Authorized Participant that exchanges securities for Creation Units will generally recognize a gain or a loss on the exchange. Any such gain or loss will be equal to the difference between the market value of the Creation Units at the time of the exchange, plus (or minus) the cash amount received (or paid), and such Authorized Participant’s aggregate basis in the securities surrendered. A person who redeems Creation Units for securities will generally recognize a gain or loss equal to the difference between the aggregate market value of the securities received plus (or minus) any cash received (or paid), and such person’s basis in the Creation Units redeemed. The Internal Revenue Service, however, may assert that a loss realized upon an exchange of securities for Creation Units cannot be deducted currently under the rules governing “wash sales,” or on the basis that there has been no significant change in the Authorized Participant’s economic position with respect to such Creation Units. Persons exchanging securities should consult their own tax advisor with respect to the applicability of the wash sale rules and the availability and timing of a deduction for any loss. In addition, when a regulated investment company redeems a shareholder in kind, the regulated investment company generally is not required to recognize taxable gains in respect of the portfolio securities it distributes to the redeeming shareholder. However, the Fund may be required to recognize taxable gain on the distribution of certain securities, and the Internal Revenue Service may assert that the Fund must recognize taxable gain in respect of certain other securities that the Fund distributes to a shareholder in exchange for Creation Units, which may increase the amount of taxable gains that the Fund would otherwise be required to distribute in order to maintain its qualification as a regulated investment company and avoid the Fund-level tax.

Any capital gain or loss realized upon a redemption of Creation Units is generally treated as long-term capital gain or loss if the Creation Units have been held for more than one year and as short-term capital gain or loss if the Creation Units have been held for one year or less. If you purchase or redeem Creation Units, you will be sent a confirmation statement showing how many Fund Shares you purchased or sold and at what price.

Authorized Participants that are dealers may be subject to special tax rules and should consult their own tax advisors regarding the tax consequences of purchasing and redeeming Creation Units in their capacity as dealers.

Treatment of Fund Expenses

Expenses incurred and deducted by the Fund will generally not be treated as income taxable to you.

Non-U.S. Investors

If you are a non-U.S. investor (i.e., an investor other than a U.S. citizen or resident or a U.S. corporation, partnership, estate or trust), you should be aware that, generally, subject to applicable tax treaties, distributions from the Fund will be characterized as dividends for U.S. federal income tax purposes (other than dividends which the Fund properly reports as capital gain dividends) and will be subject to U.S. federal income taxes, including withholding taxes, subject to certain exceptions described in the SAI.

Distributions may be subject to a U.S. withholding tax of 30% in the case of distributions to (i) certain non-U.S. financial institutions that have not entered into an agreement with the U.S. Treasury to collect and disclose certain information and are not resident in a jurisdiction that has entered into such an agreement with the U.S. Treasury and (ii) certain other non-U.S. entities that do not provide certain certifications and information about the entity’s U.S. owners. The Internal Revenue Service

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and the Department of the Treasury have issued proposed regulations providing that these withholding rules will not be applicable to the gross proceeds of share redemptions or capital gains dividends that the Fund pays.

Other Tax Matters

The foregoing is only a summary of certain federal income tax considerations of investing in the Fund under current law, which is subject to change in the future. Shareholders who are not U.S. persons within the meaning of the Code, such as non-resident aliens, foreign trusts or estates, or foreign corporations or partnerships may be subject to different U.S. federal income tax treatment.

You may also be subject to state and local taxes on distributions paid by the Fund, and sales and redemptions of Fund shares. You should consult your tax advisor for further information regarding federal, state, local and/or foreign tax consequences relevant to your specific tax situation. More information about taxes can be found in the Fund’s SAI.

Net Asset Value

The NAV of shares is determined at the close of regular trading on the New York Stock Exchange (normally 4:00 p.m. Eastern Time) on each day the New York Stock Exchange (“NYSE”) is open. NAV is computed by determining the aggregate market value of all assets of the Fund, less its liabilities, divided by the total number of shares outstanding ((assets-liabilities)/number of shares = NAV). The NYSE is closed on weekends and New Year’s Day, Martin Luther King, Jr. Day, Presidents’ Day, Good Friday, Memorial Day, Juneteenth National Independence Day, Independence Day, Labor Day, Thanksgiving Day and Christmas Day. The NAV takes into account the expenses and fees of the Fund, including management, administration, and distribution fees, which are accrued daily. The determination of NAV for the Fund for a particular day is applicable to all applications for the purchase of shares, as well as all requests for the redemption of shares, received by the Fund (or an authorized broker or agent, or its authorized designee) before the close of trading on the NYSE on that day.

Generally, securities traded or dealt in upon one or more securities exchanges (whether domestic or foreign) for which market quotations are readily available and not subject to restrictions against resale shall be valued at the last quoted sales price on the primary exchange or, in the absence of a sale on the primary exchange, at the mean between the current bid and ask prices on such exchange. Securities primarily traded in the National Association of Securities Dealers’ Automated Quotation System (“NASDAQ”) National Market System for which market quotations are readily available shall be valued using the NASDAQ official closing price. Securities that are not traded or dealt in any securities exchange (whether domestic or foreign) and for which over-the-counter market quotations are readily available generally shall be valued at the last sale price or, in the absence of a sale, at the mean between the current bid and ask price on such over-the-counter market. Debt securities not traded on an exchange may be valued at prices supplied by a pricing agent(s) based on broker or dealer supplied valuations or matrix pricing, a method of valuing securities by reference to the value of other securities with similar characteristics, such as rating, interest rate and maturity. Futures, swaps and options contracts listed for trading on a futures or options exchange or board of trade for which market quotations are generally available are valued at the last quoted sale price, or, in the absence of a sale, at the mean of the last bid and ask price. Total return swaps on exchange-listed securities are valued at the last quoted sale price, or, in the absence of a sale, at the mean of the last bid and ask price.

Securities held by the Fund are valued in accordance with policies and procedures established by the Adviser pursuant to Rule 2a‑5 under the 1940 Act and approved by and subject to the oversight of the Board of Trustees (“Valuation Procedures”). If market quotations are not readily available, securities or other assets will be valued at their fair value as determined in good faith by the Adviser in accordance with procedures approved by the Board and evaluated by the Board as to the reliability of the fair value method used. In these cases, the Fund’s NAV will reflect certain portfolio securities’ fair values rather than their market prices. Fair value pricing involves subjective judgments, and it is possible that the fair value determined for a security or other asset may be materially different than the value that could be realized upon the sale of that security or other asset. The fair value prices can differ from market prices. The Board of Trustees has designated Calamos Advisors as “valuation designee” for the Fund. The valuation designee is responsible for determining the value of the Fund’s investments. The designee may also enlist third party consultants such as an audit firm or financial officer of a security issuer on an as-needed basis to assist in determining a security-specific fair value. The Board reviews and ratifies the execution of this process and the resultant fair value prices at least quarterly to ensure the process produces reliable results.

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The Fund may use independent pricing services to assist in calculating the value of the Fund’s securities or other assets.

With respect to any portion of the Fund’s assets that are invested in one or more open-end management investment companies registered under the 1940 Act, the Fund’s net asset value is calculated based upon the net asset values of those open-end management investment companies, and the prospectuses for these companies explain the circumstances under which those companies will use fair value pricing and the effects of using fair value pricing.

Fund Service Providers

State Street Bank and Trust Company (“State Street”), located at One Congress Street, Suite 1, Boston, Massachusetts 02114‑2016, serves as the Fund’s administrator, custodian, fund accounting and transfer agent.

Calamos Financial Services LLC (“CFS”), located at 2020 Calamos Court, Naperville, Illinois 60563, serves as the principal underwriter for the following investment companies registered under the Investment Company Act of 1940, as amended: Calamos Investment Trust, Calamos Advisors Trust, Calamos Antetokounmpo Sustainable Equities Trust, Calamos ETF Trust, Calamos Aksia Alternative Credit and Income Fund, Calamos Aksia Hedged Strategies Fund, and Calamos Aksia Private Equity and Alternatives Fund. CFS serves as the principal underwriter for the new series of Calamos ETF Trust, where it serves as distributor of Creation Units for the Fund on an agency basis. The Distributor does not maintain a secondary market in Fund Shares.

Ropes & Gray LLP, located at 191 North Wacker Drive, 32nd Floor, Chicago, IL 60606, serves as legal counsel to the Trust.

Premium/Discount Information

Information showing the number of days the market price of the Fund Shares was greater (at a premium) and less (at a discount) than the Fund’s NAV for the most recently completed calendar year, and the most recently completed calendar quarters since that year (or the life of the Fund, if shorter), is available at www.calamos.com.

Investments by Other Investment Companies

Section 12(d)(1) of the 1940 Act restricts investments by investment companies in the securities of other investment companies, including Fund Shares. The SEC adopted Rule 12d1‑4 under the 1940 Act on November 19, 2020, which became effective January 19, 2021. The Fund is required to comply with the conditions of Rule 12d1‑4, which allows, subject to certain conditions, the Fund to invest in other registered investment companies beyond the limits contained in Section 12(d)(1) of the 1940 Act.

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Financial Highlights

The Fund has not commenced operations and therefore has no performance history as of the date of this prospectus. Financial information is therefore not available.

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Other Information

Continuous Offering

The method by which Creation Units of Fund Shares are created and traded may raise certain issues under applicable securities laws. Because new Creation Units of Fund Shares are issued and sold by the Fund on an ongoing basis, a “distribution,” as such term is used in the Securities Act of 1933, as amended (the “Securities Act”), may occur at any point. Broker-dealers and other persons are cautioned that some activities on their part may, depending on the circumstances, result in their being deemed participants in a distribution in a manner which could render them statutory underwriters and subject them to the prospectus delivery requirements and liability provisions of the Securities Act. For example, a broker-dealer firm or its client may be deemed a statutory underwriter if it takes Creation Units after placing an order with the Distributor, breaks them down into constituent Fund Shares and sells the Fund Shares directly to customers or if it chooses to couple the creation of a supply of new Fund Shares with an active selling effort involving solicitation of secondary market demand for Fund Shares. A determination of whether one is an underwriter for purposes of the Securities Act must take into account all the facts and circumstances pertaining to the activities of the broker-dealer or its client in the particular case, and the examples mentioned above should not be considered a complete description of all the activities that could lead to a characterization as an underwriter.

Broker-dealer firms should also note that dealers who are not “underwriters” but are effecting transactions in Fund Shares, whether or not participating in the distribution of Fund Shares, are generally required to deliver a prospectus. This is because the prospectus delivery exemption in Section 4(a)(3) of the Securities Act is not available in respect of such transactions as a result of Section 24(d) of the 1940 Act. As a result, broker-dealer firms should note that dealers who are not “underwriters” but are participating in a distribution (as contrasted with engaging in ordinary secondary market transactions) and thus dealing with the Fund Shares that are part of an overallotment within the meaning of Section 4(a)(3)(C) of the Securities Act, will be unable to take advantage of the prospectus delivery exemption provided by Section 4(a)(3) of the Securities Act. For delivery of prospectuses to exchange members, the prospectus delivery mechanism of Rule 153 under the Securities Act is only available with respect to transactions on a national exchange.

Neither MerQube, Inc. nor any of its affiliates (collectively, “MerQube”) is the issuer or producer of Calamos Least-Of Autocallable Income ETF (“CAYN”) and MerQube has no duties, responsibilities, or obligations to investors in CAYN. The index underlying CAYN is a product of MerQube and has been licensed for use by Calamos Advisors LLC. Such index is calculated using, among other things, market data or other information (“Input Data”) from one or more sources (each such source, a “Data Provider”). MerQube® is a registered trademark of MerQube, Inc. This trademark has been licensed for certain purposes by Calamos Advisors LLC in its capacity as the issuer of CAYN. CAYN is not sponsored, endorsed, sold or promoted by MerQube, any Data Provider, or any other third party, and none of such parties make any representation regarding the advisability of investing in securities generally or in CAYN particularly, nor do they have any liability for any errors, omissions, or interruptions of the Input Data, MerQube US Equity Least-Of Autocallable Index (MQAUTOWL), or any associated data. Neither MerQube nor the Data Providers make any representation or warranty, express or implied, to the owners of the shares of CAYN or to any member of the public, of any kind, including regarding the ability of the MQAUTOWL to track market performance or any asset class. MQAUTOWL are determined, composed and calculated by MerQube without regard to Calamos Advisors LLC or CAYN. MerQube and Data Providers have no obligation to take the needs of Calamos Advisors LLC or the owners of CAYN into consideration in determining, composing or calculating MQAUTOWL. Neither MerQube nor any Data Provider is responsible for and have not participated in the determination of the prices or amount of CAYN issued or sold or the timing of the issuance or sale of CAYN or in the determination or calculation of the equation by which CAYN is to be converted into cash, surrendered or redeemed, as the case may be. MerQube and Data Providers have no obligation or liability in connection with the administration, marketing or trading of CAYN. There is no assurance that investment products based on MQAUTOWL will accurately track index performance or provide positive investment returns. MerQube is not an investment advisor. Inclusion of a security within an index is not a recommendation by MerQube to buy, sell, or hold such security, nor is it considered to be investment advice.

NEITHER MERQUBE NOR ANY OTHER DATA PROVIDER GUARANTEES THE ADEQUACY, ACCURACY, TIMELINESS AND/OR THE COMPLETENESS OF MQAUTOWL, OR ANY DATA RELATED THERETO (INCLUDING DATA INPUTS) OR ANY COMMUNICATION WITH RESPECT THERETO. NEITHER MERQUBE NOR ANY OTHER DATA PROVIDERS SHALL BE SUBJECT TO ANY DAMAGES OR LIABILITY FOR ANY ERRORS, OMISSIONS, OR DELAYS THEREIN. MERQUBE AND ITS DATA PROVIDERS MAKE NO EXPRESS OR

CALAMOS LEAST-OF AUTOCALLABLE INCOME ETF

Other Information

IMPLIED WARRANTIES, AND THEY EXPRESSLY DISCLAIM ALL WARRANTIES, OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE OR USE OR AS TO RESULTS TO BE OBTAINED BY CALAMOS ADVISORS LLC, OWNERS OF CAYN, OR ANY OTHER PERSON OR ENTITY FROM THE USE OF MQAUTOWL, OR WITH RESPECT TO ANY DATA RELATED THERETO. WITHOUT LIMITING ANY OF THE FOREGOING, IN NO EVENT WHATSOEVER SHALL MERQUBE OR DATA PROVIDERS BE LIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL, PUNITIVE, OR CONSEQUENTIAL DAMAGES INCLUDING BUT NOT LIMITED TO, LOSS OF PROFITS, TRADING LOSSES, LOST TIME OR GOODWILL, EVEN IF THEY HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES, WHETHER IN CONTRACT, TORT, STRICT LIABILITY, OR OTHERWISE. THE FOREGOING REFERENCES TO “MERQUBE” AND/OR “DATA PROVIDER” SHALL BE CONSTRUED TO INCLUDE ANY AND ALL SERVICE PROVIDERS, CONTRACTORS, EMPLOYEES, AGENTS, AND AUTHORIZED REPRESENTATIVES OF THE REFERENCED PARTY.

Summary of Certain Provisions of the Second Amended and Restated Trust Instrument

The summary below is a synopsis of certain provisions contained in the Trust’s Second Amended and Restated Trust Instrument (the “Trust Instrument”). Shareholders should refer to the Trust Instrument for further information. Defined terms have the meanings contained in the Trust Instrument.

Derivative Actions

The Second Amended and Restated Trust Instrument requires, within Section 9 of Article IV, that before bringing any derivative action on behalf of the Fund, Shareholders must have made a written demand to the Board of Trustees requesting that they cause the Trust or affected Series or Class, as applicable, to file the action itself.

In order to warrant consideration, any such written demand must include at least the following:

(1)

a detailed description of the action or failure to act complained of and the facts upon which each such allegation is made;

(2)

a statement to the effect that the complaining Shareholders believe that they will fairly and adequately represent the interests of similarly situated Shareholders in enforcing the right of the Trust or the affected Series or Class, as applicable and an explanation of why the complaining Shareholders believe that to be the case;

(3)

a certification that the following requirements have been met, as well as information reasonably designed to allow the Trustees to verify that certification:

(a)

each complaining Shareholder was a Shareholder of the Trust or the affected Series or Class, as applicable, at the time of the action or failure to act complained of, or acquired the Shares afterwards by operation of law from a Person who was a Shareholder at that time; and

(b)

each complaining Shareholder was a Shareholder of the Trust or the affected Series or Class, as applicable, as of the time the demand required by Section 9 of Article IV was made; and

(4)

a certification that each complaining Shareholder will be a Shareholder of the Trust or the affected Series or Class, as applicable as of the commencement of the derivative action.

The Trust Instrument further provides that at least 10% of the Shareholders of the Trust or the affected Series or Class, as applicable, must join in bringing the derivative action. This provision does not apply to claims brought under the federal securities laws.

The Trust Instrument also provides that a copy of the derivative complaint must be served on the Trust, assuming the requirements described above have already been met and the derivative action has not been barred as further described in the Trust Instrument.

Forum and Waiver of Jury Trial

Section 10 of Article X of the Trust Instrument outlines which shareholder actions must be brought in state court and which must be brought in federal court. This section states in particular that, unless the Trust consents in writing to the selection of an alternative forum, the Federal District Courts of the United States of America shall be the sole and exclusive forum for the resolution of any complaint asserting a cause of action arising under any federal securities law. This provision may increase costs for a shareholder to bring a claim or may limit a shareholder’s ability to bring a claim in a judicial forum that they find

PROSPECTUS | October 14, 2026

Other Information

more convenient or favorable. While the enforceability of the exclusive forum provisions may be challenged, this section also provides that if any provisions of Section 10 shall be held to be invalid, illegal or unenforceable, the validity, legality and enforceability of the remaining portions will still apply.

Section 10 of Article X of the Trust Instrument also states that shareholders and all other such persons bringing any such suit, action, or proceeding in the Superior Court in the State of Delaware waive the right to a trial by jury to the fullest extent permitted by law.

CALAMOS LEAST-OF AUTOCALLABLE INCOME ETF

For more detailed information on the Fund, several additional sources of information are available to you. The Fund’s SAI, incorporated by reference into this prospectus, contains detailed information on the Fund’s policies and operation. Additional information about the Fund’s investments will be available in the annual and semi-annual reports to shareholders. In the Fund’s annual reports, once available, you will find a discussion of the market conditions and investment strategies that significantly impacted the Fund’s performance during the last fiscal period. The Fund’s most recent SAI, annual or semi-annual reports, once available, and certain other information are available free of charge by calling the Fund at
(866) 363‑9219, on the Fund’s website at www.calamos.com or through your financial advisor. Shareholders may call the toll-free number above with any inquiries.

You may obtain this and other information regarding the Fund, including the SAI and Codes of Ethics adopted by the Adviser, Distributor and the Trust, directly from the SEC. Information on the SEC’s website is free of charge. Visit the SEC’s on-line EDGAR database at http://www.sec.gov. You may also request information regarding the Fund by sending a request (along with a duplication fee) to the SEC by sending an electronic request to publicinfo@sec.gov.

$\"\"$

Calamos Least-Of Autocallable Income ETF

2020 Calamos Court
Naperville, IL 60563‑2787
866.363.9219
www.calamos.com

SEC File
#811‑22887

CAYNSTAPRO 101426

STATEMENT OF ADDITIONAL INFORMATION

\n \n \n \n \n \n \n \n \n \n \n

Fund		Ticker
Calamos Least-Of Autocallable Income ETF		CAYN

2020 Calamos Court
\nNaperville, Illinois 60563
\n866.363.9219

This Statement of Additional Information (“SAI”) relates\nto Calamos Least-Of Autocallable Income ETF (the “Fund”), a series of the Calamos ETF Trust (the “Trust”). This\nis not a prospectus, but provides information that should be read in conjunction with the prospectus for the Fund, dated October 14,\n2026 and any supplements thereto, which are incorporated herein by reference. Capitalized terms used herein that are not defined have\nthe same meanings as in the Prospectus, unless otherwise noted. A copy of the Prospectus may be obtained without charge by calling the\nFund at (866) 363-9219, visiting the Fund’s website at www.calamos.com or through your financial advisor.

References to the Investment Company Act of 1940, as amended (the “1940\nAct”), or other applicable law, will include any rules promulgated thereunder and any guidance, interpretations or modifications\nby the Securities and Exchange Commission (the “SEC”), SEC staff or other authority with appropriate jurisdiction, including\ncourt interpretations, and exemptive, no action or other relief or permission from the SEC, SEC staff or other authority.

TABLE OF CONTENTS

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

	Page
THE TRUST AND THE FUND	1
EXCHANGE LISTING AND TRADING	2
DISCLOSURE OF PORTFOLIO HOLDINGS	2
INVESTMENT OBJECTIVE	2
INVESTMENT PRACTICES	3
INVESTMENT RESTRICTIONS	14
MANAGEMENT	16
CONTROL PERSONS AND PRINCIPAL HOLDERS OF SECURITIES	27
INVESTMENT ADVISORY SERVICES	28
DISTRIBUTOR	31
OTHER COMPENSATION TO INTERMEDIARIES	32
PORTFOLIO TRANSACTIONS	33
ADDITIONAL INFORMATION CONCERNING THE FUND SHARES	34
CREATION AND REDEMPTION OF CREATION UNITS	35
DETERMINATION OF NET ASSET VALUE	43
TAXATION	44
CUSTODIAN AND TRANSFER AGENT	52
FUND ACCOUNTING AND FINANCIAL ACCOUNTING AGENT	52
MISCELLANEOUS	52
FINANCIAL STATEMENTS	53

THE TRUST AND THE FUND

The Trust was organized as a Delaware statutory trust on June 17,\n2013. The Trust is an open-end, registered management investment company. The Trust currently offers Fund Shares in forty-eight series\nof the Trust. Series other than the Fund are offered through separate prospectuses and statements of additional information and\nare not further discussed herein. The offering of the Fund’s shares (“Fund Shares”) is registered under the Securities\nAct of 1933, as amended (the “Securities Act”).

The Fund is a non-diversified, actively managed exchange-traded\nfund. The Fund offers and issues Fund Shares at net asset value (“NAV”) only in aggregations of a specified number of Fund\nShares, generally in exchange for a basket of securities constituting the portfolio holdings of a Fund, together with the deposit of\na specified cash payment, or, in certain circumstances, for an all-cash payment. Fund Shares will be listed and principally traded on\nthe NYSE Arca, Inc. (“NYSE Arca” or the “Exchange”). Fund Shares will trade on the Exchange at market prices\nthat may be below, at, or above NAV.

Unlike mutual funds, Fund Shares are not individually redeemable\nsecurities. Rather, a Fund issues and redeems Fund Shares on a continuous basis at NAV, in aggregations of a specified number of Fund\nShares (each, a “Creation Unit”). In the event of the liquidation of a Fund, the Trust may lower the number of Fund Shares\nin a Creation Unit. Financial entities known as “authorized participants” (which are discussed in greater detail below) have\ncontractual arrangements with a Fund or the Distributor to purchase and redeem Fund Shares directly with a Fund in Creation Units in\nexchange for the securities comprising the Fund and/or cash, or some combination thereof. Fund Shares are traded in the secondary market\nand elsewhere at market prices that may be at, above, or below the Fund’s NAV. Fund Shares are only redeemable in Creation Units\nby authorized participants. An authorized participant that purchases a Creation Unit of Fund Shares deposits with the Fund a “basket”\nof securities and/or other assets identified by the Fund that day, and then receives the Creation Unit of Fund Shares in return for those\nassets. The redemption process is the reverse of the purchase process: the authorized participant redeems a Creation Unit of Fund Shares\nfor a basket of securities and other assets. The basket is generally representative of the Fund’s portfolio, and together with\na cash balancing amount, it is equal to the NAV of the Fund Shares comprising the Creation Unit. Pursuant to Rule 6c-11 of the 1940\nAct (“Rule 6c-11”), the Fund may utilize baskets that are not representative of the Fund’s portfolio. Such “custom\nbaskets” are discussed in the section entitled “Creations and Redemptions of Creation Units.” Transaction fees and\nother costs associated with creations or redemptions that include cash may be higher than the transaction fees and other costs associated\nwith in-kind creations or redemptions. In all cases, conditions with respect to creations and redemptions of Fund Shares and fees will\nbe limited in accordance with the requirements of SEC rules and regulations applicable to management investment companies offering\nredeemable securities.

Unlike index-based ETFs, the Fund is “actively managed”\nand does not seek to replicate the performance of a specified index.

The Board of Trustees of the Trust (the “Board of Trustees”\nor the “Trustees”) has the right to establish additional series in the future, to determine the preferences, voting powers,\nrights and privileges thereof and to modify such preferences, voting powers, rights and privileges without shareholder approval. Fund\nShares of any series may also be divided into one or more classes at the discretion of the Trustees. The Trust or any series or class\nthereof may be terminated at any time by the Board of Trustees upon written notice to the shareholders.

CFTC REGULATION

The Fund is a commodity pool under the Commodity Exchange Act (“CEA”)\nand Calamos Advisors is registered as a “commodity pool operator” under the CEA with respect to the Fund. As a result, additional\nCFTC-mandated disclosure, reporting and recordkeeping obligations will apply with respect to the Fund. Compliance with the CFTC’s\nregulatory requirements could increase Fund expenses, adversely affecting the Fund’s total return.

EXCHANGE LISTING AND TRADING

Fund Shares are listed and traded on the NYSE Arca. Fund Shares\ntrade on the Exchange or in secondary markets at prices that may differ from their NAV or Intraday Indicative Value (“IIV”)\nbecause such prices may be affected by market forces (such as supply and demand for Fund Shares). As is the case of other securities\ntraded on an exchange, when you buy or sell Fund Shares on the Exchange or in the secondary markets your broker will normally charge\nyou a commission or other transaction charges. Further, the Trust reserves the right to adjust the price of Fund Shares in the future\nto maintain convenient trading ranges for investors (namely, to maintain a price per Share that is attractive to investors) by share\nsplits or reverse share splits, which would have no effect on the NAV.

There can be no assurance that the requirements of the Exchange\nnecessary to maintain the listing of Fund Shares of the Fund will continue to be met. The Exchange may, but is not required to, remove\nthe Fund Shares from listing if, among other things: (i) following the initial 12-month period beginning upon the commencement of\ntrading of Fund Shares, there are fewer than 50 record and/or beneficial owners of Fund Shares; (ii) the Fund is no longer eligible\nto operate in reliance on Rule 6c-11; (iii) any of the other listing requirements are not continuously maintained; or (iv) any\nevent shall occur or condition shall exist that, in the opinion of the Exchange, makes further dealings on the Exchange inadvisable.\nThe Exchange will remove the Shares of the Fund from listing and trading upon termination of the Fund.

The Fund is not sponsored, endorsed, sold or promoted by the Exchange.\nThe Exchange makes no representation or warranty, express or implied, to the owners of Fund Shares or any member of the public regarding\nthe advisability of investing in securities generally or in the Fund particularly or the ability of the Fund to achieve its objectives.\nThe Exchange has no obligation or liability in connection with the administration, marketing or trading of the Fund.

DISCLOSURE OF PORTFOLIO HOLDINGS

The Board has adopted a policy regarding the disclosure of information\nabout the Fund’s portfolio securities. Under the policy, portfolio holdings of the Fund, which will form the basis for the calculation\nof NAV on any day on which the Trust is open for business (“Business Day”), are publicly disseminated prior to the opening\nof trading on the Exchange that Business Day through financial reporting or news services, including the website www.calamos.com. In addition,\neach Business Day a portfolio composition file, which displays the basket of securities to be deposited to purchase Creation Units of\na Fund (“In-Kind Creation Basket”) and the amount of cash necessary to equal the difference between the NAV of a Creation\nUnit and the market value of the In-Kind Creation Basket (“Cash Component”), is publicly disseminated prior to the opening\nof the Exchange via the National Securities Clearing Corporation (“NSCC”).

INVESTMENT OBJECTIVE

The Fund’s investment objective is shown below:

Calamos Least-Of Autocallable Income ETF\n(the “Fund”) seeks to generate high monthly income while providing reduced downside risk through exposure to the MerQube\nUS Equity Least-Of Autocallable Index (the “Autocallable Index”). The Autocallable Index is designed to reflect the performance\nof a theoretical diversified portfolio of synthetic least-of autocallable notes (each an “Autocallable” and the theoretical\nportfolio of Autocallables, the “Index Portfolio”), the coupon, autocall and principal outcomes of which are determined by\nreference to the least-performing of a basket of three exchange-traded funds — the SPDR^® S&P 500^®\nETF Trust (“SPY”), the Invesco QQQ Trust℠, Series 1 (“QQQ”) and the iShares^® Russell\n2000^® ETF (“IWM”) (together, the “Underlying Reference Basket,” and each a “Constituent”).\nThe reduced downside risk that the Fund seeks to deliver is relative to owning a single underlying least-of autocallable note (and not\nrelative to the risk associated with investing in the Underlying Reference Basket or any Constituent), because exposure to the Autocallable\nIndex is expected to provide benefits such as reduced timing risk, diversification across multiple Autocallable notes (i.e., not subject\nto a single maturity barrier), and contingent maturity barriers that may help preserve capital over time.

The Fund’s investment objective is non-fundamental and may be\nchanged by a vote of the Fund’s Board, without shareholder approval.

The Fund is a non-diversified, actively managed exchange-traded\nfund (“ETF”) that, under normal market conditions, seeks to invest at least 80% of its total assets in U.S. Treasuries, cash,\ncash equivalents, “box spreads” (including box spread ETFs) and unfunded total return swaps that provide exposure to the\nMerQube US Equity Least-Of Autocallable Index (the “Autocallable Index”). The Fund will not attempt to replicate or track\nthe Autocallable Index but will instead use financial instruments such as total return swaps to gain exposure to the level of the Autocallable\nIndex. The Fund intends to make distributions to investors monthly in amounts that are determined in part by reference to the Autocallable\nIndex. The Autocallable Index is designed to reflect the collective performance of a theoretical portfolio of approximately 52 to 156\nsynthetic least-of autocallable notes arranged in a laddered structure and staggered entry points with similar fixed parameters (the\n“Parameters”) as described within the section of the prospectus titled “Index Portfolio Characteristics”.

INVESTMENT PRACTICES

The prospectus contains information concerning the Fund’s investment\nobjective and principal investment strategies and risks. This Statement of Additional Information provides additional information concerning\ncertain securities and strategies used by the Fund and their associated risks.

In pursuing its investment objective, the Fund expects to invest as\ndescribed below and in the Fund’s prospectus. The table below indicates whether the Fund invests in the securities and instruments\nlisted as part of its principal (P) or non-principal (N) investment strategies.

Unless otherwise noted, all investment policies and restrictions described\nin the Prospectus and Statement of Additional Information are measured at the time of the transaction in the security. If market action\naffecting Fund securities (including, but not limited to, appreciation, depreciation, or a credit rating event) causes a Fund to exceed\nan investment policy or restriction, Calamos Advisors LLC (“Calamos Advisors” or the “Adviser”) is not required\nto take immediate action. Under normal market conditions, however, Calamos Advisors will not make any acquisitions that will make a Fund\nfurther outside the investment restriction.

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

INVESTMENTS\n AND INVESTMENT-RELATED PRACTICES		Calamos\n \n Least-Of \n Autocallable \n Income \n ETF
Box Spreads		P
Equity Securities		P
FLexible EXchange^® Options (“FLEX\n Options”)		P
Illiquid Securities Other Than Total Return Swaps		N
Options on Securities and Indexes		P
Other Investment Companies		P
Repurchase Agreements		N
Reverse Repurchase Agreements and Other Borrowings		N
Swap Agreements		P
Temporary Investments		N
U.S. Government Obligations		P

BOX SPREADS

A Box Spread is an offsetting set of options, which may include Flexible\nExchange Options (“FLEX Options”). Box Spreads consist of a synthetic long position coupled with an offsetting synthetic short\nposition through a combination of options contracts on a reference asset at the same expiration date. The synthetic long position consists\nof (i) buying a call option and (ii) selling a put option, each on the same reference asset and each with the same strike price\nand expiration date. The synthetic short position consists of (i) buying a put option and (ii) selling a call option, each on\nthe same reference asset and each with the same expiration date as the synthetic long but with a different strike price from the synthetic\nlong position. The difference between the strike prices of the synthetic long position and the synthetic short position determines the\nexpiration value (or value at maturity) of the Box Spread. An important feature of the Box Spread construction process is that it seeks\nto eliminate market risk tied to price movements associated with the underlying options’ reference asset. Once the Box Spread is\ninitiated, its return from the initiation date through expiration will not change due to price movements in the underlying options’\nreference assets. The Fund may purchase Box Spreads on various indices or securities based on risk and return considerations. Box Spreads\nare expected to have return characteristics similar to cash equivalents. The box spreads are constructed using two FLEX Option positions\n(long call, long put), three FLEX Option positions (long call, short call, long put), or four FLEX Option positions (long call, short\ncall, long put, short put) at two different strike prices with the same maturity seeking to provide a riskless arbitrage that captures\nthe present value of the future cash flow.

EQUITY SECURITIES

Equity securities include common and preferred stocks, warrants, rights,\nand depositary receipts. An investment in the equity securities of a company represents a proportionate ownership interest in that company.\nTherefore, a Fund participates in the financial success or failure of any company in which it has an equity interest.

Equity investments are subject to greater fluctuations in market value\nthan other asset classes as a result of such factors as the issuer’s business performance, investor perceptions, stock market trends\nand general economic conditions. Equity securities are subordinated to bonds and other debt instruments in a company’s capital structure\nin terms of priority to corporate income and liquidation payments. See the prospectus for additional information regarding equity investments\nand their risks.

FLEX OPTIONS

FLEX Options are customized option contracts available through national\nsecurities exchanges that are guaranteed for settlement by the OCC. FLEX Options are listed on a U.S. national securities exchange. FLEX\nOptions provide investors with the ability to customize assets referenced by the options, exercise prices, exercise styles (i.e., American-style,\nexercisable any time prior as well as on to the expiration date, or European-style, exercisable only on the option expiration date) and\nexpiration dates, while achieving price discovery in competitive, transparent auctions markets and avoiding the counterparty exposure\nof OTC options positions. Each option contract entitles the holder thereof to purchase (for the call options) or sell (for the put options)\nthe reference asset at the strike price.

The OCC guarantees performance by each of the counterparties to the\nFLEX Options and Listed Options, becoming the “buyer for every seller and the seller for every buyer”, with the goal of protecting\nclearing members and options traders from counterparty risk.

Trading FLEX Options involves risks different from, and possibly greater\nthan, the risks associated with investing directly in securities or in other types of options. FLEX Options, like other listed options,\nare traded on the U.S. options markets and are issued by OCC. However, unlike other options, the terms of FLEX Options are not all standardized.\nWhen a FLEX Option is purchased and sold in an opening transaction, the parties to the transaction have the flexibility, within limitations\nset forth in the rules of the options market on which the transaction occurs, to fix certain of the option’s terms. The flexibility\nto fix certain terms is what makes FLEX Options different from other types of options. Because many of the terms of FLEX Options are not\nstandardized, it is less likely that there will be an active secondary market in which holders and writers of such options will be able\nto close out their positions by offsetting sales and purchases. Because FLEX Options have variable terms that are fixed by the parties,\nthere are no preestablished series of FLEX Options. Rather, any different series of FLEX Options may be created and outstanding at any\ngiven time as a result of the various designations of variable terms that are made in different transactions. Secondary trading interest\nin FLEX Options may therefore be spread over a larger number of series than the trading interest in other options, the trading interest\nin any particular series of FLEX Options may be very limited, the secondary markets in FLEX Options may be less deep, liquid and continuous\nthan the markets in other options on the same underlying interests, and the premiums for FLEX Options may not correlate with premiums\nfor such other options.

In the event that trading in the FLEX Options is limited or absent,\nthe value of the Fund’s FLEX Options may decrease. In a less liquid market for the FLEX Options, liquidating the FLEX Options may\nrequire the payment of a premium (for written FLEX Options) or acceptance of a discounted price (for purchased FLEX Options) and may take\nlonger to complete. A less liquid trading market may adversely impact the value of the FLEX Options and Fund Shares and result in the\nFund being unable to achieve its investment objective. Less liquidity in the trading of the Fund’s FLEX Options could have an impact\non the prices paid or received by the Fund for the FLEX Options in connection with creations and redemptions of the Fund Shares. Depending\non the nature of this impact to pricing, the Fund may be forced to pay more for redemptions (or receive less for creations) than the price\nat which it currently values the FLEX Options. Such overpayment or under collection may impact the value of the Fund and whether the Fund\ncan satisfy its investment objective. Additionally, in a less liquid market for the FLEX Options, the liquidation of a large number of\noptions may more significantly impact the price. A less liquid trading market may adversely impact the value of the FLEX Options and the\nvalue of your investment. The trading in FLEX Options may be less deep and liquid than the market for certain other exchange-traded options,\nnon-customized options or other securities. The Fund also is subject to the risk that the OCC will become insolvent or otherwise be unable\nto meet its obligations, which could cause the Fund to suffer losses which may be significant.

The Fund may not experience substantial upside participation from specific\nFLEX Option positions and certain FLEX Option positions may expire worthless.

OCC may base its calculations of the margin requirements for positions\nin a series of FLEX Options on an estimate derived from data and factors OCC deems pertinent in respect of quotations and transactions\nin that options series and in other options series. Alternatively, OCC may fix such margin requirements at a level it deems necessary\nto protect the respective interests of OCC, the clearing members and the public. As a result, the Fund’s margin requirements for\npositions in FLEX Options may differ from—and may be significantly greater than—the margin requirements applicable to similar\npositions in other options on the same underlying interest.

ILLIQUID SECURITIES OTHER THAN TOTAL RETURN SWAPS

A Fund may invest up to 15% of its net assets under regulatory rules,\ntaken at market value, in illiquid investments that are assets, including any securities that are not readily marketable either because\nthey are restricted securities or for other reasons. Restricted securities are securities that are subject to restrictions on resale because\nthey have not been registered for sale under the Securities Act of 1933, as amended (“Securities Act”). A position in restricted\nsecurities might adversely affect the liquidity and marketability of a portion of a Fund’s portfolio, and a Fund might not be able\nto sell or dispose of its holdings in such securities promptly or at reasonable prices. In those instances where a Fund is required to\nhave restricted securities held by it registered prior to sale by a Fund and a Fund does not have a contractual commitment from the issuer\nor seller to pay the costs of such registration, the gross proceeds from the sale of securities would be reduced by the registration costs\nand underwriting discounts. Any such registration costs are not included in the percentage limitation on a Fund’s investment in\nrestricted securities.

The liquidity of an investment will be determined based on relevant\nmarket, trading and investment specific considerations as set out in a Fund’s liquidity risk management program (the “Liquidity\nProgram”) as required by Rule 22e-4 under the 1940 Act (the “Liquidity Rule”). Illiquid investments may trade at\na discount to comparable, more liquid investments and a Fund may not be able to dispose of illiquid investments in a timely fashion or\nat their expected prices. If illiquid investments exceed 15% of a Fund’s net assets, the Liquidity Rule and the Liquidity Program\nwill require that certain remedial actions be taken.

OPTIONS ON SECURITIES AND INDEXES

A Fund may purchase and sell (write) call options and purchase put\noptions on securities and indexes.

A put option gives the purchaser of the option, upon payment of a premium,\nthe right to sell, and the writer the obligation to buy, the underlying security index, or other instrument at the exercise price. For\ninstance, a Fund’s purchase of a put option on a security might be designed to protect its holdings in the underlying instrument\n(or, in some cases, a similar instrument) against a substantial decline in the market value by giving such Fund the right to sell such\ninstrument at the option exercise price. A call option, upon payment of a premium, gives the purchaser of the option the right to buy,\nand the seller the obligation to sell, the underlying instrument at the exercise price.

A Fund’s purchase of a call option on a security, index, or other\ninstrument might be intended to protect it against an increase in the price of the underlying instrument that it intends to purchase in\nthe future by fixing the price at which it may purchase such instrument. A Fund may purchase and sell (write) call and purchase put exchange\nlisted options and over-the-counter (“OTC”) options. Exchange listed options on securities are issued by a regulated intermediary\nsuch as the OCC, which guarantees the performance of the obligations of the parties to such options. The discussion below uses the OCC\nas an example, but is also applicable to other financial intermediaries.

With certain exceptions, OCC issued and exchange listed options generally\nsettle by physical delivery of the underlying security or currency, although in the future cash settlement may become available. Index\noptions are cash settled for the net amount, if any, by which the option is “in-the-money” (i.e., where the value of the underlying\ninstrument exceeds, in the case of a call option, or is less than, in the case of a put option, the exercise price of the option) at the\ntime the option is exercised. Frequently, rather than taking or making delivery of the underlying instrument through the process of exercising\nthe option, listed options are closed by entering into offsetting purchase or sale transactions that do not result in ownership of the\nnew option.

OTC options are purchased from or sold to sellers or purchasers (“Option\nCounterparties”) through direct bilateral agreement with such Option Counterparties. In contrast to exchange listed options, which\ngenerally have standardized terms and performance mechanics, all the terms of an OTC option, including such terms as method of settlement,\nterm, exercise price, premium, guarantees and security, are set by negotiation of the parties. A Fund will only sell (write) OTC options\n(other than OTC currency options) that are subject to a buy-back provision permitting a Fund to require the Option Counterparty to sell\nthe option back to a Fund at a formula price within seven days. A Fund generally is expected to enter into OTC options that have cash\nsettlement provisions, although it is not required to do so. The staff of the SEC currently takes the position that OTC options purchased\nby a Fund, and portfolio securities “covering” the amount of a Fund’s obligation pursuant to an OTC option sold by it\n(or the amount of assets equal to the formula price for the repurchase of the option, if any, less the amount by which the option is “in\nthe money”) are illiquid, and are subject to a Fund’s limitation on investing no more than 15% of its net assets in illiquid\nsecurities.

A Fund may also purchase call and put and sell (write) call options\non securities indexes and other financial indexes. Options on securities indexes and other financial indexes are similar to options on\na security or other instrument except that, rather than settling by physical delivery of the underlying instrument, they settle by cash\nsettlement, i.e., an option or an index gives the holder the right to receive, upon exercise of the option, an amount of cash if the closing\nlevel of the index upon which the option is based exceeds, in the case of a call, or is less than, in the case of a put, the exercise\nprice of the option (except if, in the case of an OTC option, physical delivery is specified). This amount of cash is equal to the excess\nof the closing price of the index over the exercise price of the option, which also may be multiplied by a formula value. The seller of\nthe option is obligated, in return for the premium received, to make delivery of this amount. The gain or loss on an option on an index\ndepends on price movements in the instruments making up the market, market segment, industry or other composite on which the underlying\nindex is based, rather than price movements in individual securities, as is the case with respect to options on securities.

A Fund will sell (write) call options. A written option will be considered\n“covered” to the extent it has entered into an offsetting transaction or otherwise has segregated or earmarked cash or liquid\nassets equal to its uncovered obligations under the written option. For example, a call option written by a Fund could be covered by purchasing\nan offsetting call option, by purchasing or holding the underlying reference security or asset (or a security convertible into the underlying\nreference security or asset), or by segregating or earmarking cash or liquid assets equal to the exercise price of the written option\n(or such amount as is not otherwise covered by an offsetting transaction). A Fund writing a call option on an index would be considered\nas holding an offsetting position to the extent such Fund owned portfolio securities substantially correlating with the movement of the\nunderlying reference index.

If an option written by a Fund expires, a Fund realizes a capital gain\nequal to the premium received at the time the option was written. If an option purchased by a Fund expires, a Fund realizes a capital\nloss equal to the premium paid.

A Fund will realize a capital gain from a closing purchase transaction\nif the cost of the closing option is less than the premium received from writing the option, or, if it is more, such Fund will realize\na capital loss. If the premium received from a closing sale transaction is more than the premium paid to purchase the option, a Fund will\nrealize a capital gain or, if it is less, a Fund will realize a capital loss. The principal factors affecting the market value of a put\nor a call option include supply and demand, interest rates, the current market price of the underlying security, asset or index in relation\nto the exercise price of the option, the volatility of the underlying security, asset or index, and the time remaining until the expiration\ndate.

A put or call option purchased by a Fund is an asset of a Fund, valued\ninitially at the premium paid for the option. The premium received for an option written by a Fund is recorded as a deferred credit. The\nvalue of an option purchased or written is marked-to-market daily and is valued at the closing price on the exchange on which it is traded\nor, if not traded on an exchange or no closing price is available, at the mean between the last bid and asked prices.

RISKS ASSOCIATED WITH OPTIONS

There are several risks associated with transactions in options. For\nexample, there are significant differences between the securities markets, the currency markets, the markets for the assets referenced\nby a futures contract, and the options markets that could result in an imperfect correlation among these markets, causing a given transaction\nnot to achieve Calamos Advisors’ objective. A decision as to whether, when and how to use options involves the exercise of skill\nand judgment, and even a well-conceived transaction may be unsuccessful to some degree because of market behavior or unexpected events.

A Fund’s ability to utilize options successfully will depend\non Calamos Advisors’ ability to predict pertinent market investments, which cannot be assured. A Fund’s ability to close out\nits position as a purchaser or seller (writer) of an Options Clearing Corporation (“OCC”) or exchange-listed put or call option\nis dependent, in part, upon the liquidity of the option market. Among the possible reasons for the absence of a liquid option market on\nan exchange are: (i) insufficient trading interest in certain options; (ii) restrictions on transactions imposed by an exchange;\n(iii) trading halts, suspensions or other restrictions imposed with respect to particular classes or series of options or underlying\nasset including reaching daily price limits; (iv) interruption of the normal operations of the OCC or an exchange; (v) inadequacy\nof the facilities of an exchange or OCC to handle current trading volume; or (vi) a decision by one or more exchanges to discontinue\nthe trading of options (or a particular class or series of options), in which event the relevant market for that option on that exchange\nwould cease to exist, although outstanding options on that exchange would generally continue to be exercisable in accordance with their\nterms. If a Fund were unable to close out an option that it has purchased on an asset, it would have to exercise the option in order to\nrealize any profit or the option would expire and become worthless. If a Fund were unable to close out a covered call option that it had\nwritten on an asset, it would not be able to sell the underlying asset until the option expired. As the writer of a covered call option\non an asset, a Fund foregoes, during the option’s life, the opportunity to profit from increases in the market value of the asset\ncovering the call option above the sum of the premium and the exercise price of the call. The hours of trading for listed options may\nnot coincide with the hours during which the underlying financial instruments are traded. To the extent that the option markets close\nbefore the markets for the underlying financial instruments, significant price and rate movements can take place in the underlying markets\nthat cannot be reflected in the option markets.

Unless the parties provide for it, there is no central clearing or\nguaranty function in an over-the-counter (“OTC”) option. As a result, if the Option Counterparty (as described above under\n“Options on Securities and Indexes”) fails to make or take delivery of the security, currency or other instrument underlying\nan OTC option it has entered into with a Fund or fails to make a cash settlement payment due in accordance with the terms of that option,\na Fund will lose any premium it paid for the option as well as any anticipated benefit of the transaction. Accordingly, Calamos Advisors\nmust assess the creditworthiness of each such Option Counterparty or any guarantor or credit enhancement of the Option Counterparty’s\ncredit to determine the likelihood that the terms of the OTC option will be satisfied. If a Fund purchases an OTC option from a counterparty\nthat is not registered with and regulated by any financial regulator, these risks will be particularly pronounced. Such a counterparty\nis not subject to the same degree of regulation as a U.S. regulated financial institution, such as a bank, registered broker-dealer or\nregistered swap dealer. They may be subject to different, often less comprehensive, compliance, risk management, reporting, disclosure\nand capital requirements than registered financial institutions, and may be subject to no such requirements. For example, counterparties\nthat are registered with a financial regulator typically are subject to examination and enforcement authority of a regulator, and to fitness\nand financial requirements and requirements to segregate customer funds from their own funds, to account separately for customer funds\nand positions, to implement and maintain compliance policies and procedures, and to make books and records available for inspection by\nthe SEC, the CFTC, self-regulatory organizations or banking regulators. Financial difficulty, fraud or misrepresentation at any of these\ninstitutions could lead to significant losses as well as materially impair the operational capabilities or financial position of the Fund.

The Fund is not subject to any limit on its exposure to any one\ncounterparty nor to a requirement that counterparties with whom they enter into contracts maintain a minimum credit rating. A Fund may\ninvest in OTC options through a limited number of counterparties and events that affect the creditworthiness of any of those counterparties\nmay have a pronounced effect on the Fund. Arrangements to trade OTC options may be available with only one or a few counterparties, and\nliquidity problems therefore might be greater than when numerous counterparties are available to enter into such arrangements. A Fund\nis not restricted from dealing with any particular counterparty or from concentrating any or all transactions with one counterparty.\nThe ability of a Fund to transact business with any one of a number of counterparties, the lack of any meaningful and independent evaluation\nof such counterparties’ financial capabilities and the absence of a regulated market to facilitate settlement may increase the\npotential for losses by the Fund.

A Fund may purchase and sell (write) call options on securities and\nindexes. Even though a Fund will receive the option premium to help protect it against loss, a call sold by a Fund exposes such Fund during\nthe term of the option to possible loss of opportunity to realize appreciation in the market price of the underlying security or instrument\nand may require a Fund to hold the security or instrument that it might otherwise have sold. In addition, a loss on a call option sold\nmay be greater than the premium received.

OTHER INVESTMENT COMPANIES

The Fund may invest in the securities of other investment companies\nto the extent that such investments are consistent with the Fund’s investment objectives and permissible under the 1940 Act. Such\nother investment companies may include, without limitation, other registered investment companies that in turn invest in box spreads.\nUnder one provision of the 1940 Act, the Fund may not acquire the securities of other investment companies if, as a result, (i) more\nthan 10% of the Fund’s total assets would be invested in securities of other investment companies, (ii) such purchase would\nresult in more than 3% of the total outstanding voting securities of any one investment company being held by the Fund or (iii) more\nthan 5% of the Fund’s total assets would be invested in any one investment company. In some instances, the Fund may invest in an\ninvestment company in excess of these limits. For example, the Fund may invest in other registered investment companies, such as mutual\nfunds, closed-end funds and ETFs, including affiliated funds, and in business development companies in excess of the statutory limits\nimposed by the 1940 Act in reliance on Rule 12d1-4 under the 1940 Act. These investments would be subject to the applicable conditions\nof Rule 12d1-4, which in part would affect or otherwise impose certain limits on the investments and operations of the underlying\nfund. The Fund, as a holder of the securities of other investment companies, will bear its pro rata portion of the other investment companies’\nexpenses, including advisory fees. These expenses will be in addition to the direct expenses incurred by the Fund. In the event the Fund\ninvests in another affiliated fund (the “Acquired Fund”), the portion of the Fund’s Investment Management Fee equal\nto the advisory fee payable to the Acquired Fund (based on average daily net assets invested) is waived.

REPURCHASE AGREEMENTS

As part of its strategy for the temporary investment of cash, a Fund\nmay enter into “repurchase agreements” pertaining to U.S. Government securities with member banks of the Federal Reserve System\nor primary dealers (as designated by the Federal Reserve Bank of New York) in such securities. A Fund may invest in repurchase agreements,\nprovided that a Fund may not invest more than 15% of its net assets in illiquid securities, including repurchase agreements maturing in\nmore than seven days, and any other illiquid securities. A repurchase agreement arises when a Fund purchases a security and simultaneously\nagrees to resell it to the vendor at an agreed upon future date. The resale price is greater than the purchase price, reflecting an agreed\nupon market rate of return that is effective for the period of time a Fund holds the security and that is not related to the coupon rate\non the purchased security.

Such agreements generally have maturities of no more than seven days\nand could be used to permit a Fund to earn interest on assets awaiting long-term investment. A Fund requires continuous maintenance by\nthe custodian for a Fund’s account in the Federal Reserve/Treasury Book Entry System of collateral in an amount equal to, or in\nexcess of, the market value of the securities that are the subject of a repurchase agreement. In the event of a bankruptcy or other default\nof a seller of a repurchase agreement, a Fund could experience both delays in liquidating the underlying security and losses, including:\n(a) possible decline in the value of the underlying security during the period while a Fund seeks to enforce its rights thereto;\n(b) possible subnormal levels of income and lack of access to income during this period; and (c) expenses of enforcing its rights.\nIn an effort to reduce these risks, Calamos Advisors will monitor the creditworthiness of the firms with which a Fund enters into repurchase\nagreements.

The SEC has finalized rules that will require certain transactions\ninvolving U.S. Treasuries, including repurchase agreements, to be centrally cleared. Compliance with these rules is expected to be\nrequired in the middle of 2027. Although the impact of these rules on the Fund is difficult to predict, they may reduce the availability\nor increase the costs of such transactions and may adversely affect the Fund’s performance.

REVERSE REPURCHASE AGREEMENTS AND OTHER BORROWINGS

A Fund may enter into reverse repurchase agreements, and economically\nsimilar transactions to the extent permitted under the leverage limitations of the 1940 Act and a Fund’s investment restrictions\ndescribed below. A reverse repurchase agreement is a repurchase agreement in which a Fund is the seller of, rather than the investor in,\nsecurities and agrees to repurchase them at an agreed-upon time and price. A reverse repurchase agreement enables a Fund to obtain cash\nto satisfy unusually heavy redemption requests or for other temporary or emergency purposes without needing to sell portfolio securities,\nor to earn additional income on portfolio securities, such as Treasury bills or notes. Use of a reverse repurchase agreement may be preferable\nto a regular sale and later repurchase of securities because it avoids certain market risks and transaction costs.

A Fund also may effect simultaneous purchase and sale transactions\nthat are known as “sale-buybacks.” A sale-buyback is similar to a reverse repurchase agreement, except that in a sale-buyback,\nthe counterparty who purchases the security is entitled to receive any principal or interest payments made on the underlying security\npending settlement of a Fund’s repurchase of the underlying security.

The SEC has finalized rules that will require certain transactions\ninvolving U.S. Treasuries, including reverse repurchase agreements, to be centrally cleared. Compliance with these rules is expected\nto be required in the middle of 2027. Although the impact of these rules on the Fund is difficult to predict, they may reduce the\navailability or increase the costs of such transactions and may adversely affect the Fund’s performance.

SWAP AGREEMENTS

The Fund expects to enter into swap agreements. In a standard “swap”\ntransaction, two parties agree to exchange the returns, differentials in rates of return or some other amount earned or realized on the\n“notional amount” of predetermined investments or instruments, which may be adjusted for an interest factor. Some swaps are\nstructured to include exposure to a variety of different types of investments or market factors, such as interest rates, commodity prices,\nnon-U.S. currency rates, mortgage securities, corporate borrowing rates, security prices, indexes or inflation rates. Swap agreements\nmay be negotiated bilaterally and traded OTC between two parties or, in some instances, must be transacted through a futures commission\nmerchant and cleared through a clearinghouse that serves as a central counterparty. Certain risks are reduced (but not eliminated) if\na fund invests in cleared swaps. Certain standardized swaps, including certain credit default swaps, are subject to mandatory clearing,\nand more are expected to be in the future. The counterparty risk for cleared derivatives is generally lower than for uncleared derivatives,\nbut cleared contracts are not risk-free.

Swap agreements may increase or decrease the overall volatility of\nthe Fund’s investments and the price of Fund Shares. The performance of swap agreements may be affected by a change in the specific\ninterest rate, currency or other factors that determine the amounts of payments due to and from the Fund. If a swap agreement calls for\npayments by the Fund, the Fund must be prepared to make such payments when due.

Generally, swap agreements have fixed maturity dates that are agreed\nupon by the parties to the swap. The swap agreement can be terminated before the maturity date generally only under limited circumstances,\nand can be transferred by a party only with the prior written consent of the other party. The Fund may be able to eliminate its exposure\nunder a swap agreement either by assignment or other disposition, or by entering into an offsetting swap agreement with the same party\nor a similarly creditworthy party. If the counterparty is unable to meet its obligations under the contract, declares bankruptcy, defaults\nor becomes insolvent, the Fund may not be able to recover the money it expected to receive under the contract. The Fund expects to obtain\nexposure through swap agreements with a single counterparty or a limited number of counterparties and will likely continue to do so for\nthe foreseeable future. Counterparty risks may be more pronounced for this Fund due to the single or limited number of counterparties\nused by it.

A swap agreement can be a form of leverage, which can magnify the Fund’s\ngains or losses. The risk of loss generally is related to a notional principal amount, even if the parties have not made any initial investment.\nNotional amounts of swap transactions are not subject to any limitations, and swap contracts may expose a Fund to unlimited risk of loss.\nCertain derivatives have the potential for unlimited loss, regardless of the size of the initial investment.

The use of swaps can cause the Fund to be subject to additional regulatory\nrequirements, which may generate additional Fund expenses.

The Fund monitors any swaps with a view towards ensuring that the Fund\nremains in compliance with all applicable regulatory, investment and tax requirements.

Many swap agreements are complex and their valuation often requires\nsubjective modeling and judgment, which increases the risk of mispricing or incorrect valuation. Valuation risk is more pronounced when\na Fund enters into a swap with specialized terms. Incorrect valuations may result in increased cash payment requirements to counterparties,\nunder collateralization and/or errors in calculation of a Fund’s NAV. If a default occurs by the other party to such transaction,\na Fund will have contractual remedies pursuant to the agreements related to the transaction, which may be limited by applicable law in\nthe case of a counterparty’s insolvency. Also, because swap transactions typically involve a contract between the two parties, such\nswap investments can be extremely illiquid, as it is uncertain as to whether another counterparty would wish to take assignment of the\nrights under the swap contract at a price acceptable to a Fund.

Total Return Swaps. In a total return swap (“TRS”),\none party pays a rate of interest in exchange for the total rate of return on another investment.

An unfunded TRS is a financial derivative contract where one party\n(the payer) agrees to make payments to the other party (the receiver) based on the total return of an underlying asset, such as a stock,\nbond, or index, without the payer needing to own the underlying asset. In return, the receiver pays a fixed or floating interest rate,\noften tied to a reference rate such as SOFR, to the payer. What makes it “unfunded” is that neither party initially posts\nthe full value of the underlying asset, which reduces the need for upfront capital. Instead, the swap is typically collateralized with\nthe exchange of variation margin (and in some cases, initial margin) to mitigate counterparty risk. Essentially, the TRS allows one party\nto gain exposure to the underlying asset’s economic performance (price appreciation and income) while the other party benefits from\nthe interest payments and price depreciation of the underlying asset.

Unfunded TRS are often used for hedging, leveraging positions, or gaining\naccess to assets that may otherwise be challenging to hold directly. They can also allow investors to remain off-balance-sheet, meaning\nthe assets or liabilities related to the swap may not appear on their financial statements, depending on applicable accounting rules.

TEMPORARY INVESTMENTS

A Fund may make temporary investments without limitation when Calamos\nAdvisors determines that a defensive position is warranted, or as a reserve for possible cash needs. Such investments may be in money\nmarket instruments, consisting of obligations of, or guaranteed as to principal and interest by, the U.S. Government or its agencies or\ninstrumentalities; certificates of deposit, bankers’ acceptances and other obligations of domestic banks having total assets of\nat least $500 million and that are regulated by the U.S. Government, its agencies or instrumentalities; commercial paper rated in the\nhighest category by a recognized rating agency; cash; and repurchase agreements. See “Exhibit A — Description of Ratings”\nfor a description of ratings of certain rating agencies and their significance.

U.S. GOVERNMENT OBLIGATIONS

U.S. Government Obligations include securities that are issued or guaranteed\nby the U.S. Treasury or by various U.S. Government agencies and instrumentalities. U.S. Treasury obligations (“U.S. Treasuries”)\ninclude Treasury bills, Treasury notes, and Treasury bonds. U.S. Treasuries also include the separate principal and interest components\nof U.S. Treasuries that are traded under the Separate Trading of Registered Interest and Principal of Securities (“STRIPS”)\nprogram. U.S. Treasury obligations are backed by the full faith and credit of the U.S. Obligations issued or guaranteed by U.S. Government\nagencies and instrumentalities may be supported by any of the following: (a) the full faith and credit of the U.S., (b) the\nright of the issuer to borrow an amount limited to a specific line of credit from the U.S. Treasury, (c) the discretionary authority\nof the U.S. Treasury to lend to such Government agency or instrumentality, or (d) the credit of the agency or instrumentality.

Government agencies that issue or guarantee securities backed by the\nfull faith and credit of the U.S. include the Government National Mortgage Association (“GNMA”) and the Small Business Administration.\nGovernment agencies and instrumentalities that issue or guarantee securities not backed by the full faith and credit of the U.S. include\nthe Federal Farm Credit Banks, the Federal Home Loan Banks, the Federal Home Loan Mortgage Corporation (“FHLMC”), the Federal\nNational Mortgage Association (“FNMA”), the Federal Land Bank, the Bank for Cooperatives, the Federal Intermediate Credit\nBank, the Federal Financing Bank, the Resolution Funding Corporation, the Financing Corporation of America and the Tennessee Valley Authority.\nIn the case of securities not backed by the full faith and credit of the U.S., the investor must look principally to the agency issuing\nor guaranteeing the obligation for ultimate repayment and may not be able to assert a claim against the U.S. in the event the agency or\ninstrumentality does not meet its commitment.

In September 2008, the U.S. Treasury and the Federal Housing Finance\nAgency (“FHFA”) announced that FNMA and FHLMC had been placed in conservatorship. The conservatorship is still in effect as\nof the date of this SAI and has no specified termination date. There can be no assurance as to when or how the conservatorship will be\nterminated or whether FNMA or FHLMC will continue to exist following the conservatorship or what their respective business structures\nwill be during or following the conservatorship. Since that time, FNMA and FHLMC have received significant capital support through U.S.\nTreasury preferred stock purchases, as well as Treasury and Federal Reserve purchases of their mortgage-backed securities (“MBS”).\nThe FHFA and the U.S. Treasury (through its agreement to purchase FNMA and FHLMC preferred stock) have imposed strict limits on the size\nof their mortgage portfolios. The FHFA, as conservator, has the power to repudiate any contract entered into by FNMA or FHLMC prior to\nits appointment if it determines that performance of the contract is burdensome and repudiation of the contract promotes the orderly administration\nof FNMA’s or FHLMC’s affairs. Further, the FHFA has the right to transfer or sell any asset or liability of FNMA or FHLMC\nwithout any approval, assignment or consent. If FHFA were to transfer any such guaranty obligation to another party, holders of FNMA or\nFHLMC MBS would have to rely on that party for satisfaction of the guaranty obligation and would be exposed to the credit risk of that\nparty. No assurance can be given that the Federal Reserve or the U.S. Treasury will ensure that FNMA and FHLMC remain successful in meeting\ntheir obligations with respect to the debt and mortgage-backed securities that they issue.

In addition, the problems faced by FNMA and FHLMC, resulting in their\nbeing placed into federal conservatorship and receiving significant U.S. Government support, have sparked serious debate among federal\npolicy makers regarding the continued role of the U.S. Government in providing liquidity for mortgage loans. In December 2011, Congress\nenacted the Temporary Payroll Tax Cut Continuation Act (“TCCA”) of 2011 which, among other provisions, requires that FNMA\nand FHLMC increase their single-family guaranty fees by at least 10 basis points and remit this increase to Treasury with respect to all\nloans acquired by FNMA and FHLMC on or after April 1, 2012 and before January 1, 2022. Serious discussions among policymakers\ncontinue, however, as to whether FNMA and FHLMC should be nationalized, privatized, restructured, or eliminated altogether. FNMA reported\nin the second quarter of 2014 that there was “significant uncertainty regarding the future of our company, including how long the\ncompany will continue to exist in its current form, the extent of our role in the market, what form we will have, and what ownership interest,\nif any, our current common and preferred stockholders will hold in us after the conservatorship is terminated and whether we will continue\nto exist following conservatorship.” FHLMC faces similar uncertainty about its future role. FNMA and FHLMC also are the subject\nof several continuing legal actions and investigations over certain accounting, disclosure or corporate governance matters, which (along\nwith any resulting financial restatements) may continue to have an adverse effect on the guaranteeing entities.

A Fund may invest in securities issued or guaranteed by any of the\nentities listed above or by any other agency established or sponsored by the U.S. Government, provided that the securities are otherwise\npermissible investments of a Fund. Certain U.S. Government Obligations that have a variable rate of interest readjusted no less frequently\nthan annually will be deemed to have a maturity equal to the period remaining until the next readjustment of the interest rate.

A Fund’s yield will fluctuate due to changes in interest rates,\neconomic conditions, quality ratings and other factors. The prepayment experience of the mortgages underlying mortgage-related securities,\nsuch as obligations issued by GNMA, may affect the value of, and return on, an investment in such securities.

RECENT MARKET CONDITIONS

In the past decade, financial markets throughout the world have experienced\nincreased volatility, depressed valuations, decreased liquidity and heightened uncertainty and turmoil. This turmoil resulted in unusual\nand extreme volatility in the equity and debt markets, in the prices of individual securities and in the world economy. Events that have\ncontributed to these market conditions include, but are not limited to, major cybersecurity events, geopolitical events (including wars,\nterror attacks and public health emergencies), measures to address budget deficits, downgrading of sovereign debt, declines in oil and\ncommodity prices, dramatic changes in currency exchange rates, and public sentiment. In addition, many governments and quasi-governmental\nentities throughout the world have responded to the turmoil with a variety of significant fiscal and monetary policy changes, including,\nbut not limited to, direct capital infusions into companies, and new monetary programs.

Federal, state, and other governments, their regulatory agencies, or\nself-regulatory organizations may take actions that affect the regulation of the instruments in which a Fund invests, or affect the issuers\nof such instruments, in ways that are unforeseeable. There is a possibility of future regulatory changes altering, perhaps to a material\nextent, the nature of an investment in a Fund or the ability of a Fund to continue to implement its investment strategies. The U.S. government\nhas enacted and is continuing to implement legislation that provides for regulation of the derivatives market, including clearing, margin,\nreporting and registration requirements. The CFTC, SEC, and other federal regulators have adopted and continue to develop rules and\nregulations enacting the provisions of the Dodd-Frank Wall Street Reform and Consumer Protection Act (the “Dodd-Frank Act”).\nThe Dodd-Frank Act has and will continue to change the way in which the U.S. financial system is supervised and regulated.

Governments or their regulatory agencies may also acquire distressed\nassets from financial institutions and acquire ownership interests in those institutions. The implications of government ownership and\ndisposition of these assets are unclear, and such ownership or disposition may have positive or negative effects on the liquidity, valuation\nand performance of a Fund’s portfolio holdings.

Following financial crises, such as the global financial crisis fueled\nby the COVID-19 pandemic, the Federal Reserve generally attempted to stabilize the U.S. economy and support the U.S. economic recovery\nby keeping the federal funds rate low. Following such periods, the Federal Reserve terminated certain of its market support activities\nand raised interest rates. With continued economic recovery and the cessation of certain market support activities, a Fund may face a\nheightened level of interest rate risk as a result of a rise or increased volatility in interest rates. These policy changes may reduce\nliquidity for certain of a Fund’s investments, causing the value of a Fund’s investments and share price to decline.

Global regulation of the derivatives market in particular has undergone\nsubstantial change since the financial crisis of 2008, including clearing, margin, trade execution, reporting and registration requirements.\nBecause these requirements continue to evolve, their full impact on the Fund remains unclear. These and other new rules and regulations\ncould, among other things, restrict a Fund’s ability to engage in derivatives transactions (for example, by making certain types\nof derivatives transactions no longer available to the Fund) and/or increase the costs of such derivatives transactions, and the Fund\nmay be unable to execute its investment strategy as a result. Global requirements may also result in increased uncertainty about counterparty\ncredit risk, and they may also limit the flexibility of a Fund to protect its interests in the event of an insolvency of a derivatives\ncounterparty. In the event of a counterparty’s (or its affiliate’s) insolvency, a Fund’s ability to exercise remedies,\nsuch as the termination of transactions, netting of obligations and realization on collateral, could be stayed or eliminated under special\nresolution regimes adopted in the United States, the European Union, the United Kingdom and various other jurisdictions. Such regimes\nprovide government authorities with broad authority to intervene when a financial institution is experiencing financial difficulty. In\nparticular, with respect to counterparties who are subject to such proceedings in the European Union or the United Kingdom, the liabilities\nof such counterparties to a Fund could be reduced, eliminated, or converted to equity in such counterparties (sometimes referred to as\na “bail in”).

As economies and financial markets throughout the world are increasingly\ninterconnected, the likelihood increases that geopolitical conflicts in one country or region will adversely impact markets or issuers\nin other countries or regions, including in ways that are difficult to predict or foresee. Economic, financial or political events, trading\nand tariff arrangements, terrorism, natural disasters, rapid technological developments, such as artificial intelligence, and other circumstances\nin one country or region could have profound impacts on global economies or markets. Widespread disease and virus epidemics, such as\nthe recent coronavirus outbreak, could likewise be highly disruptive, adversely affecting individual companies, sectors, industries,\nmarkets, currencies, interest and inflation rates, credit ratings, investor sentiment, and other factors affecting the value of the Fund’s\ninvestments. The impacts of these conflicts or events can be exacerbated by failures of governments and societies to respond adequately\nto a geopolitical conflict and subsequent emerging events or threats. As a result, whether or not the Fund invests in securities of issuers\nlocated in or with significant exposure to the countries directly affected, the value and liquidity of the Fund’s investments may\nbe negatively affected.

Trade disputes may affect investor and consumer confidence and adversely\naffect financial markets and the broader economy, perhaps suddenly and to a significant degree. The U.S. government has indicated its\nintent to alter its approach to international trade policy and, in some cases, to renegotiate or potentially terminate certain existing\nbilateral or multilateral trade agreements and treaties with foreign countries and has made proposals and taken actions related thereto.\nIn addition, the U.S. government has recently imposed tariffs on certain foreign goods and has indicated a willingness to impose tariffs\non imports of other products. Some foreign governments, including China, have instituted retaliatory tariffs on certain U.S. goods and\nhave indicated a willingness to impose additional tariffs on U.S. products. Other countries, including Mexico, have threatened retaliatory\ntariffs on certain U.S. products. Global trade disruption, significant introductions of trade barriers, and bilateral trade frictions,\ntogether with any future downturns in the global economy resulting therefrom, could adversely affect the financial performance of a Fund\nand its investments. U.S. trade policy has changed rapidly in the past, and may do so in the future, and it may be an ongoing source of\ninstability, potentially resulting in significant currency fluctuations and/or having other adverse effects on international markets,\ninternational trade agreements, and/or other existing cross-border cooperation arrangements (whether economic, tax, fiscal, legal, regulatory,\nor otherwise). To the extent trade disputes escalate globally, there could be additional significant impacts on the sectors or industries\nin which a Fund invests and other adverse impacts on the Fund’s overall performance.

Inflation may reduce the intrinsic value of increases in the value\nof a Fund. Inflation risk is the risk that the value of assets or income from investments will be less in the future as inflation decreases\nthe value of money. As inflation increases, the value of a Fund’s assets can decline.

Recent technological developments in, and the increasingly widespread\nuse of, artificial intelligence, including machine learning technology and generative artificial intelligence (“AI”), may\npose risks to the Fund. For instance, the economy may be significantly impacted by the advanced development and increased regulation of\nAI. As AI is used more widely, the profitability and growth of Fund holdings may be impacted, which could significantly impact the overall\nperformance of the Fund. The legal and regulatory frameworks within which AI operates continue to rapidly evolve, and it is not possible\nto predict the full extent of current or future risks related thereto.

INVESTMENT IN A SUBSIDIARY

As determined necessary or advisable by the Fund, the Fund may invest\na portion of its assets in a wholly-owned subsidiary (each, a “Subsidiary”), organized under the laws of the Cayman Islands.\nInvestment in the Subsidiary is expected to provide the Fund with exposure to the Autocallable Index within the limitations of Subchapter\nM of the Internal Revenue Code of 1986, as amended (the “Code”) and Internal Revenue Service guidance. The Subsidiary may\ninvest primarily in derivative instruments, including Swap Agreements. To the extent that the Fund invests in the Subsidiary, the Fund\nmay be subject to the risks associated with the above-mentioned derivative instruments and other securities, which are discussed elsewhere\nin the Fund’s Prospectus and this SAI. To comply with the asset diversification test applicable to a RIC (discussed elsewhere in\nthis SAI), the Fund intends to limit its investments in such subsidiary to 25% of the Fund’s total assets at the end of each taxable\nquarter.

Although the Subsidiary may be considered similar to investment companies,\nit is not registered under the 1940 Act and, unless otherwise noted in the Fund’s Prospectus and this SAI, is not subject to all\nof the investor protections of the 1940 Act and other U.S. regulations. The Board of Trustees, however, has oversight responsibility for\nthe investment activities of the Fund, including its investment in its respective subsidiary. In addition, the Fund is the sole shareholder\nof its respective Subsidiary, and it is not currently expected that shares of a Subsidiary will be sold or offered to other investors.\nChanges in the laws of the United States and/or the Cayman Islands could result in the inability of the Fund and/or a Subsidiary to operate\nas described in the Fund’s Prospectus and this SAI and could negatively affect the Fund and its shareholders.

TAX RISK

The Fund intends to elect and to qualify each year to be treated as\na regulated investment company (“RIC”) under Subchapter M of the Code. To qualify and maintain its status as a RIC, the Fund\nmust derive at least 90% of its gross income each year from “qualifying income,” meet certain diversification tests at the\nend of each quarter and meet an annual distribution test. For purposes of the qualifying income requirement, the treatment of the swaps\nand other derivatives that provide exposure to the Autocallables is not entirely clear, and thus whether the income and gain therefrom\nis qualifying income is uncertain. If the Fund were to treat income or gain from particular instruments linked to the Autocallables as\nqualifying income, an adverse determination or future guidance by the Internal Revenue Service with respect to the treatment of income\nor gain from those investments may adversely affect the Fund’s ability to qualify as a RIC. For purposes of the diversification\ntest, the identification of the issuer (or, in some cases, issuers) of a particular Fund investment can depend on the terms and conditions\nof that investment. In particular, there is no published Internal Revenue Service guidance or case law on how to determine the “issuer”\nof certain derivatives that the Fund will enter into. An adverse determination or future guidance by the Internal Revenue Service with\nrespect to issuer identification for the Fund’s investments may adversely affect the Fund’s ability to qualify as a RIC. If\nthe Fund does not qualify as a RIC for any taxable year and certain relief provisions are not available, the Fund’s taxable income\nwill be subject to tax at the Fund level and to a further tax at the shareholder level when such income is distributed.

INVESTMENT RESTRICTIONS

The Fund is classified as a non-diversified, open-end management investment\ncompany. Except as noted below, the Fund operates under the following investment restrictions and may not:

(i)  act as an underwriter of securities, except\ninsofar as it may be deemed an underwriter for purposes of the Securities Act on disposition of securities acquired subject to legal or\ncontractual restrictions on resale;

(ii)  purchase or sell real estate (although\nit may purchase securities secured by real estate or interests therein, or securities issued by companies that invest in real estate or\ninterests therein), commodities or commodity contracts, except that the Fund may enter into (a) futures, options and options on futures,\n(b) forward contracts and (c) other financial transactions not requiring the delivery of physical commodities;

(iii)  make loans, but this restriction shall\nnot prevent a Fund from (a) investing in debt obligations, (b) investing in repurchase agreements or (c) lending portfolio\nsecurities, provided, however, that it may not lend securities if, as a result, the aggregate value of all securities loaned would exceed\n33% of its total assets (taken at market value at the time of such loan);

(iv)  borrow, except from banks, other affiliated\nfunds and other entities to the extent permitted under the 1940 Act;^1,2,3

(v)  invest in a security if more than 25% of\na Fund’s total assets (taken at market value at the time of a particular purchase) would be invested in the securities of issuers\nin any particular industry or group of industries, except to the extent that the underlying reference indices of the autocallable yield\nnotes invest more than 25% of its assets in an industry or group of industries. This restriction does not apply to securities issued or\nguaranteed by the U.S. Government, its agencies or instrumentalities, or securities of other investment companies.⁴

¹ The Fund does not intend to purchase securities when\nits borrowings exceed 5% of total assets.

² The Fund’s borrowing practices are limited by the\n1940 Act. Currently, under the 1940 Act, a Fund may borrow in an aggregate amount not exceeding 33 1/3% of its total assets, including\nthe proceeds of borrowings, for any purpose, but borrowings from entities other than banks may not exceed 5% of its total assets and\nmay be only as a temporary measure for extraordinary or emergency purposes, unless a Fund has received an exemptive order from the SEC\npermitting it to borrow from other affiliated funds in excess of 5% of its total assets.

³ Certain trading practices and investments, such as reverse\nrepurchase agreements, may be considered to be borrowings or involve leverage and thus are subject to the Investment Company Act restrictions.\nIn accordance with Rule 18f-4 under the Investment Company Act, when a Fund engages in reverse repurchase agreements and similar\nfinancing transactions, a Fund may either (i) maintain asset coverage of at least 300% with respect to such transactions and any\nother borrowings in the aggregate, or (ii) treat such transactions as “derivatives transactions” and comply with Rule 18f-4\nwith respect to such transactions. Short-term credits necessary for the settlement of securities transactions and arrangements with respect\nto securities lending will not be considered to be borrowings under the policy. Practices and investments that may involve leverage but\nare not considered to be borrowings are not subject to the policy.

⁴ As of the date hereof, it is anticipated that more\nthan 25% of the Fund’s assets will have exposure to the information technology sector.

(vi)  issue any senior security, except to the\nextent permitted under the 1940 Act;⁵

The above restrictions are fundamental policies and may not be changed\nwith respect to a Fund without the approval of a “majority” of the outstanding shares of a Fund, which for this purpose means\nthe approval of the lesser of

(a) more than 50% of the outstanding voting securities\nof a Fund or

(b) 67% or more of the outstanding shares if the holders\nof more than 50% of the outstanding shares of a Fund are present or represented at the meeting by proxy.

In addition to the fundamental restrictions listed above, the Fund\nhas adopted the following as non-fundamental policies:

(a)  To the extent other Calamos Funds invest\nin a Fund in reliance on section 12(d)(1)(G), a Fund may not acquire any securities of registered open-end investment companies or unit\ninvestment trusts in reliance on section 12(d)(1)(F) or (G) of the 1940 Act;⁶

⁵ Currently, under the 1940 Act, a “senior security”\ndoes not include any promissory note or evidence of indebtedness where the indebtedness is for temporary purposes only and in an amount\nnot exceeding 5% of the value of the total assets of the issuer at the time the loan is made. A loan is presumed to be for temporary\npurposes if it is repaid within 60 days and is not extended or renewed.

⁶ Under Section 12(d)(1)(A) of the 1940 Act, a\nFund generally must limit its investment in other investment companies so that, as determined immediately after a Fund invests in another\ninvestment company: (i) not more than 3% of the outstanding voting shares of any one investment company will be owned by a Fund;\n(ii) not more than 5% of the value of its total assets will be invested in the securities of any one investment company; and (iii) not\nmore than 10% of the value of its total assets will be invested in the aggregate in securities of investment companies as a group, except\nas permitted under the 1940 Act, the rules thereunder or SEC exemptive relief. Currently, under the 1940 Act, the rules thereunder\nand SEC exemptive relief, a Fund may invest in other investment companies in excess of the above limitations if certain requirements are\nmet, including (i) that a Fund complies with Rule 12d1-4 under the 1940 Act or (ii) that any Fund whose shares are acquired\nby another Fund in accordance with Section 12(d)(1)(G) of the 1940 Act shall not purchase securities of a registered open-end\ninvestment company or registered unit investment trust in reliance on either Section 12(d)(1) (F) or Section 12(d)(1)(G) of\nthe 1940 Act. A Fund may also invest without limitation in money market funds, provided a Fund complies with Rule 12d1-1 under the\n1940 Act. These limitations do not apply in connection with a merger, consolidation, reorganization or acquisition of substantially all\nthe assets of another investment company.

(b)  A Fund may not invest in companies for the\npurpose of exercising control or management;

(c)  A Fund may not purchase securities on margin\n(except for use of such short-term credits as are necessary for the clearance of transactions, including transactions in options, futures\nand options on futures), or participate on a joint or a joint and several basis in any trading account in securities, except in connection\nwith transactions in options, futures and options on futures;

(d)  A Fund may not make short sales of securities,\nexcept that a Fund may make short sales of securities (i) if a Fund owns an equal amount of such securities, or owns securities that\nare convertible or exchangeable, without payment of further consideration, into an equal amount of such securities, (ii) other than\nthose described in clause (i), provided that no more than 20% of its net assets would be deposited with brokers as collateral or allocated\nto segregated accounts in connection with all outstanding short sales other than those described in clause (i).

The non-fundamental investment restrictions above may be changed by\nthe Board of Trustees without shareholder approval. Notwithstanding the foregoing investment restrictions, a Fund may purchase securities\npursuant to the exercise of subscription rights. Far Eastern and European corporations frequently issue additional capital stock by means\nof subscription rights offerings to existing shareholders at a price substantially below the market price of the shares. The failure to\nexercise such rights would result in a Fund’s interest in the issuing company being diluted. The market for such rights is not well\ndeveloped in all cases and, accordingly, a Fund may not always realize full value on the sale of rights. The exception applies in cases\nwhere the limits set forth in the investment restrictions would otherwise be exceeded by exercising rights or would have already been\nexceeded as a result of fluctuations in the market value of a Fund’s portfolio securities with the result that a Fund would be forced\neither to sell securities at a time when it might not otherwise have done so, or to forego exercising the rights.

MANAGEMENT

TRUSTEES AND OFFICERS

The management of the Trust, including general supervision of the duties\nperformed for the Funds under the investment management agreement between the Trust and Calamos Advisors, is the responsibility of its\nBoard of Trustees. Each trustee elected will hold office for the lifetime of the Trust or until such trustee’s earlier resignation,\ndeath or removal; however, each trustee who is not an interested person of the Trust shall retire as a trustee at the end of the calendar\nyear in which the trustee attains the age of 75 years.

The following table sets forth each trustee’s name, year of birth,\nposition(s) with the Trust, number of portfolios in the Calamos Fund Complex overseen, principal occupation(s) during the past\nfive years and other directorships held, and date first elected or appointed. Each trustee oversees each series of the Trust, including\nthe Fund.

TRUSTEES WHO ARE INTERESTED PERSONS OF THE TRUST:

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

NAME \n AND \n YEAR OF \n BIRTH	POSITION(S) \n AND \n LENGTH OF \n TIME \n WITH THE \n TRUST	PORTFOLIOS \n IN \n FUND \n COMPLEX \n OVERSEEN	PRINCIPAL\n \n OCCUPATION(S) \n DURING THE PAST 5 \n YEARS \n AND OTHER \n DIRECTORSHIPS	EXPERIENCE, \n QUALIFICATIONS, \n ATTRIBUTES, \n SKILLS FOR BOARD \n MEMBERSHIP
John P. Calamos, Sr. (1940)*	Chairman, Trustee and President (since 2014)	76	Founder, Chairman and Global Chief Investment Officer,\n Calamos Asset Management, Inc. (“CAM”), Calamos Investments LLC (“CILLC”), Calamos Advisors LLC and\n its predecessor (“Calamos Advisors”) and Calamos Wealth Management LLC (“CWM”); Global Chief Investment Officer,\n Calamos Antetokounmpo Asset Management LLC, doing business as CGAM (“CGAM”); Director, CAM; and previously Chief Executive\n Officer, Calamos Financial Services LLC and its predecessor (“CFS”), CAM, CILLC, Calamos Advisors, and CWM	Served for multiple years as a trustee of the Trust;\n more than 25 years of experience in the financial services industry; experience serving on boards of other entities, including other\n investment companies; and earned a Masters of Business Administration degree
John S. Koudounis (1966)*	Trustee (since September 2025) and Vice President\n (since 2016)	79^^	President (since February 2021) and Chief Executive\n Officer, CAM, CILLC, Calamos Advisors, CWM, and CFS (since 2016); Chairman and Chief Executive Officer (since 2022), CGAM; Director,\n CAM (since 2016); prior thereto President and Chief Executive Officer (2010-2016), Mizuho Securities USA Inc.	More than 25 years of experience in the financial\n services industry; experience serving on boards of other entities, including other investment companies

TRUSTEES WHO ARE NOT INTERESTED PERSONS OF THE TRUST:

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

NAME\n \n AND \n YEAR OF \n BIRTH	POSITION(S) \n AND \n LENGTH OF \n TIME \n WITH THE \n TRUST	PORTFOLIOS \n IN \n FUND \n COMPLEX^ \n OVERSEEN	PRINCIPAL \n OCCUPATION(S) \n DURING THE PAST 5 \n YEARS \n AND OTHER \n DIRECTORSHIPS	EXPERIENCE, \n QUALIFICATIONS, \n ATTRIBUTES, \n SKILLS FOR BOARD \n MEMBERSHIP
Hugh P. Armstrong (1961)	Trustee (since September 2025)	76	Partner (1997-2021) of PricewaterhouseCoopers LLP\n (professional services firm) (held various positions from 1988-1997); Chair of the Board of Trustees of Escuela De Guadalupe School\n (since 2024 and Trustee 2014-2017 and since 2021); Trustee and Treasurer of Denver Ballet Guild Endowment Trust (since 2021); Director\n of the Friends of Queen’s University of Belfast (since 2024); Former Chair of the Board and Trustee of St. Mary’s Academy\n (2004-2012); Former Chair and President of the Learning Source (1999-2004)	More than 25 years of experience in the financial\n services industry
Virginia G. Breen (1964)	Trustee (since 2015)	76	Private Investor; Trustee, UBS NY Fund Cluster (open-end\n funds) (since 2023)*; Director, Paylocity Holding Corporation (since 2018); Trustee, Neuberger Berman Private Equity Registered\n Funds (registered private equity funds) (since 2015); Director, UBS A&Q Fund Complex (closed-end funds) (since 2008)***;\n Trustee, Jones Lang LaSalle Income Property Trust, Inc. (REIT) (2004-2023); Director, Tech and Energy Transition Corporation\n (blank check company) (2021-2023)	Served for multiple years as a trustee of the Trust;\n more than 25 years of experience in the financial services industry; experience serving on boards of other entities, including other\n investment companies; and earned a Masters of Business Administration degree
Jeffrey S. Phlegar (1966)	Trustee (since September 2025)	76	Chairman and CEO of MacKay Shields (2011-2024);\n EVP and Chief Investment Officer AllianceBernstein (1988-2011); former Senior member of the Management and M&A Committees of\n New York Life Investment Management, LLC (2018-Q1/2024); Chairman of the Plainview Funds (Irish QIAF) Board of Directors (2013-Q1/2024);\n Advisory Committee Member - Brewer Lane Ventures Fund I & II (2020-Present)	More than 25 years of experience in the financial\n services industry; experience serving on boards of other entities, including other investment companies; and earned a Masters of\n Business Administration degree

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

William R. Rybak (1951)	Trustee (since 2014)	76	Private investor; Chairman (since\n 2016) and Director (since 2010), Christian Brothers Investment Services Inc.; Trustee, Jackson Credit Opportunities Fund (since 2023),\n Jackson Real Assets Fund (since 2024) (interval funds), JNL Series Trust and JNL Investors Series Trust (since 2007), JNL\n Variable Fund LLC (2007-2020), Jackson Variable Series Trust (2018-2020) and JNL Strategic Income Fund LLC (2007-2018), (open-end\n mutual funds)*****; formerly Director, Private Bancorp (2003-2017); Executive Vice President and Chief Financial Officer, Van Kampen\n Investments, Inc. and subsidiaries (investment manager) (until 2000)	Served for multiple years as\n a trustee of the Trust; more than 25 years of experience in the financial services industry; experience serving on boards of other\n entities, including other investment companies; and earned a Masters of Business Administration degree
Karen L. Stuckey (1953)	Trustee (since 2022)	76	Partner (1990-2012) of PricewaterhouseCoopers LLP\n (professional services firm) (held various positions from 1975-1990); Member of Executive, Nominating, and Audit Committees and Chair\n of Finance Committee (1992-2006); formerly, Trustee, Denver Board of Oppenheimer Funds (open-end mutual funds) (2012-2019)	More than 25 years of experience in the financial\n services industry; experience serving on boards of other entities, including other investment companies
Christopher M. Toub (1959)	Trustee (since 2022)	79^^	Private investor; formerly Director of Equities,\n AllianceBernstein LP (until 2012)	More than 25 years of experience in the financial\n services industry; experience serving on boards of other entities, including other investment companies; and earned a Masters of\n Business Administration degree
Lloyd A. Wennlund (1957)	Trustee (since 2022)	76	Board Member, Mutual Fund Directors Forum (2023-present);\n Trustee and Chairman, Datum One Series Trust (since 2020)******; Expert Affiliate, Bates Group, LLC (financial services consulting\n and expert testimony firm) (since 2018); Executive Vice President, The Northern Trust Company (1989-2017); President and Business\n Unit Head of Northern Funds and Northern Institutional Funds (1994-2017); Director, Northern Trust Investments (1998-2017); Governor\n (2004-2017) and Executive Committee member (2011-2017), Investment Company Institute Board of Governors; Member, Securities\n Industry Financial Markets Association (SIFMA) Advisory Council, Private Client Services Committee and Private Client Steering Group\n (2006-2017); Board Member, Chicago Advisory Board of the Salvation Army (2011-2019)	More than 25 years of experience in the financial\n services industry; experience serving on boards of other entities, including other investment companies and earned a Masters of Business\n Administration degree

^ The Fund Complex consists of Calamos Investment Trust, Calamos\nAdvisors Trust, Calamos Convertible Opportunities and Income Fund, Calamos Convertible and High Income Fund, Calamos Strategic Total Return\nFund, Calamos Global Total Return Fund, Calamos Global Dynamic Income Fund, Calamos Dynamic Convertible and Income Fund, Calamos Long/Short\nEquity & Dynamic Income Trust, Calamos ETF Trust, Calamos Antetokounmpo Sustainable Equities Trust and Calamos Aksia Alternative\nCredit and Income Fund, Calamos Aksia Private Equity and Alternatives Fund, and Calamos Aksia Hedged Strategies Fund.

^^ Messrs. Koudounis and Toub are the only Trustees of the Trust\nwho oversee Calamos Aksia Alternative Credit and Income Fund, Calamos Aksia Private Equity and Alternatives Fund, and Calamos Aksia Hedged\nStrategies Fund.

* Messrs. Calamos and Koudounis are trustees who are each an “interested\nperson” of the Trust as defined in the 1940 Act because each is an officer of the Trust and is an affiliated person of Calamos Advisors\nand CFS.

** Overseeing forty-one portfolios in fund complex.

*** Overseeing nineteen portfolios in fund complex.

**** Overseeing four portfolios in fund complex.

***** Overseeing 134 portfolios in fund complex.

****** Overseeing eleven portfolios in fund complex.

The address of each trustee is 2020 Calamos Court, Naperville, Illinois\n60563.

OFFICERS. The preceding table gives information about John P.\nCalamos, Sr., who is Chairman, Trustee, and President of the Trust and John S. Koudounis, who is Trustee and Vice President of the\nTrust. The following table sets forth each other officer’s name, year of birth, position with the Trust and date first appointed\nto that position, and principal occupation(s) during the past five years. Each officer serves until his or her successor is chosen\nand qualified or until his or her resignation or removal by the Board of Trustees.

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

NAME AND \nYEAR OF \nBIRTH	POSITION(S) \nWITH TRUST	PRINCIPAL OCCUPATION(S)
Stephen Atkins (1965)	Treasurer (since 2022)	Senior Vice President, Head of Fund Administration (since February 2020), Calamos Advisors; prior thereto Consultant, Fund Accounting and Administration, Vx Capital Partners (March 2019-February 2020); Chief Financial Officer and Treasurer of SEC Registered Funds, and Senior Vice President, Head of European Special Purpose Vehicles Accounting and Administration, Avenue Capital Group (2010-2018)
Daniel Dufresne (1974)	Vice President (since 2022)	Executive Vice President and Chief Operating Officer, CAM, CILLC, Calamos Advisors, and CWM (since April 2021); President, CGAM (since 2022); prior thereto Citadel (1999-2020); Partner (2008-2020); Managing Director, Global Treasurer (2008-2020); Global Head of Operations (2011-2020); Global Head of Counterparty Strategy (2018-2020); Senior Advisor to the COO (2020); CEO, Citadel Clearing LLC (2015-2020)

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

Thomas E. Herman (1961)	Vice President (since 2016) and Chief Financial Officer (2016-2017 and since 2019)	Executive Vice President (since February 2021) and Chief Financial Officer, CAM, CILLC, Calamos Advisors, and CWM (since 2016); Chief Financial Officer and Treasurer, CGAM (since 2022); prior thereto, Chief Financial Officer and Treasurer, Harris Associates (2010-2016)
Walter Kelly (1970)	Chief Compliance Officer (since 2025)	Senior Vice President, Chief Compliance Officer\n - Calamos Funds (since 2025); Chief Compliance Officer – Calamos Advisors (since 2026); Co- Chief Compliance Officer - Calamos\n Advisors (2025-2026); prior thereto, General Counsel, Cedar Pine, LLC (2021-2025); Chief Compliance Officer SBB Research Group, LLC\n (2021-2025); Managing Director Nuveen Investments (2017-2020), Senior Vice President (2008-2017) and Chief Compliance Officer Nuveen\n Funds (2006-2020)
Thomas P. Kiley III (1968)	Vice President (since 2024)	Senior Vice President, Chief Distribution Officer (since 2024), CAM, CILLC, and Calamos Advisors; Principal Executive Officer and Chief Distribution Officer (since 2024), CFS; Vice President (since 2024), CGAM; prior thereto Managing Director, RIA Eastern Divisional Sales Manager, Blackrock Investments, Inc. (2017-2024)
Erik D. Ojala (1975)	Vice President and Secretary (since 2023)	Senior Vice President, General Counsel and Secretary, CAM, CILLC, Calamos Advisors, CWM (since 2023); Chief Legal Officer, CGAM (since 2023); General Counsel and Secretary, CFS (since 2023); Chief Compliance Officer, CFS (since 2026); prior thereto, Executive Vice President and General Counsel (2017-2023), Secretary (2010-2023) and Chief Compliance Officer (2021-2023), Harbor Capital Advisors, Inc.; Director and Secretary (2019-2023) and Chief Compliance Officer (2022-2023), Harbor Trust Company, Inc.; Director, Executive Vice President (2017-2023) and Chief Compliance Officer (2017-2021, 2022-2023), Harbor Funds Distributors, Inc.; Director (2017-2023), Assistant Secretary (2014-2023) and Chief Compliance Officer (2022-2023), Harbor Services Group, Inc.; Chief Compliance Officer, Harbor ETF Trust (2021-2023); and Chief Compliance Officer of Harbor Funds (2017-2023)

The address of each officer is 2020 Calamos Court, Naperville, Illinois\n60563.

COMMITTEES OF THE BOARD OF TRUSTEES. The Trust’s Board\nof Trustees has established five standing committees: the Executive Committee, the Dividend Committee, the Audit Committee, the Valuation\nCommittee and the Governance Committee.

Executive Committee. Messrs. John Calamos and Christopher\nToub are members of the executive committee, which has authority during intervals between meetings of the Board of Trustees to exercise\nthe powers of the board, with certain exceptions. John Calamos is an interested trustee of the Trust.

Dividend Committee. Mr. John Calamos serves as the sole\nmember of the dividend committee. The dividend committee is authorized, subject to Board review, to declare distributions on the Fund\nShares of the Trust’s series in accordance with such series’ distribution policies, including, but not limited to, regular\ndividends, special dividends and short- and long-term capital gains distributions.

Audit Committee. Messrs. Armstrong, Phlegar, Rybak (Chair),\nToub and Wennlund and Mses. Breen and Stuckey serve on the audit committee. The audit committee operates under a written charter adopted\nand approved by the board. The audit committee selects independent auditors, approves services to be rendered by the auditors, monitors\nthe auditors’ performance, reviews the results of the Trust’s audit and responds to other matters deemed appropriate by the\nboard. All members of the audit committee are independent trustees of the Trust.

Valuation Committee. Messrs. Armstrong, Phlegar, Rybak,\nToub, and Wennlund (Chair) and Mses. Breen and Stuckey serve on the valuation committee. The valuation committee operates under a written\ncharter approved by the board. The valuation committee oversees valuation matters of the Trust delegated to the valuation designee, including\nthe fair valuation determinations and methodologies proposed and utilized by the valuation designee, reviews the Trust’s valuation\nprocedures and their application by the valuation designee, reviews pricing errors and procedures for calculation of net asset value of\neach series of the Trust and responds to other matters deemed appropriate by the board.

Governance Committee. Messrs. Armstrong, Phlegar, Rybak,\nToub and Wennlund and Mses. Breen (Chair) and Stuckey serve on the governance committee. The governance committee operates under a written\ncharter adopted and approved by the board. The governance committee oversees the independence and effective functioning of the Board of\nTrustees and endeavors to be informed about good practices for fund boards. It also makes recommendations to the board regarding compensation\nof independent trustees. The governance committee also functions as a nominating committee by making recommendations to the Board of Trustees\nregarding candidates for election as non- interested trustees. The governance committee looks to many sources for recommendations of qualified\ntrustees, including current trustees, employees of Calamos Advisors, current shareholders of a Fund, search firms that are compensated\nfor their services and other third-party sources. Any such search firm identifies and evaluates potential candidates, conducts screening\ninterviews and provides information to the governance committee with respect to the individual candidates and the market for available\ncandidates. In making trustee recommendations, the governance committee considers a number of factors, including a candidate’s background,\nintegrity, knowledge and relevant experience. These factors are set forth in an appendix to the committee’s charter. Any prospective\ncandidate is interviewed by the trustees and officers, and references are checked. The governance committee will consider shareholder\nrecommendations regarding potential trustee candidates that are properly submitted to the governance committee for its consideration.

A Fund shareholder who wishes to propose a trustee candidate must submit\nany such recommendation in writing via regular mail to the attention of the Trust’s Secretary, at the address of the Trust’s\nprincipal executive offices. The shareholder recommendation must include:

● the number and class of all shares of the Trust’s\nseries owned beneficially or of record by the nominating shareholder at the time the recommendation is submitted and the dates on which\nsuch shares were acquired, specifying the number of shares owned beneficially;

● a full listing of the proposed candidate’s education,\nexperience (including knowledge of the investment company industry, experience as a director or senior officer of public or private companies,\nand directorships on other boards of other registered investment companies), current employment, date of birth, business and residence\naddress, and the names and addresses of at least three professional references;

●  information as to whether the candidate is, has been\nor may be an “interested person” (as such term is defined in the 1940 Act) of the Trust, Calamos Advisors or any of its affiliates,\nand, if believed not to be or have been an “interested person,” information regarding the candidate that will be sufficient\nfor the committee to make such determination;

●  the written and signed consent of the candidate to be\nnamed as a nominee and to serve as a trustee of the Trust, if elected;

●  a description of all arrangements or understandings\nbetween the nominating shareholder, the candidate and/or any other person or persons (including their names) pursuant to which the shareholder\nrecommendation is being made, and if none, so specify;

●  the class or series and number of all shares of the\nTrust’s series owned of record or beneficially by the candidate, as reported by the candidate; and

●  such other information that would be helpful to the\ngovernance committee in evaluating the candidate.

The governance committee may require the nominating shareholder to\nfurnish other information it may reasonably require or deem necessary to verify any information furnished pursuant to the procedures delineated\nabove or to determine the qualifications and eligibility of the candidate proposed by the nominating shareholder to serve as a trustee.\nIf the nominating shareholder fails to provide such additional information in writing within seven days of receipt of written request\nfrom the governance committee, the recommendation of such candidate will be deemed not properly submitted for consideration, and the governance\ncommittee is not required to consider such candidate.

Unless otherwise specified by the governance committee’s chairman\nor by legal counsel to the non-interested trustees, the Trust’s Secretary will promptly forward all shareholder recommendations\nto the governance committee’s chairman and the legal counsel to the non-interested trustees, indicating whether the shareholder\nrecommendation has been properly submitted pursuant to the procedures adopted by the governance committee for the consideration of trustee\ncandidates nominated by shareholders.

Recommendations for candidates as trustees will be evaluated, among\nother things, in light of whether the number of trustees is expected to change and whether the trustees expect any vacancies. During periods\nwhen the governance committee is not actively recruiting new trustees, shareholder recommendations will be kept on file until active recruitment\nis under way. After consideration of a shareholder recommendation, the governance committee may dispose of the shareholder recommendation.

In addition to the above committees, there is a valuation designee,\nappointed by the Board of Trustees, comprised of officers of the Trust and employees of Calamos Advisors.

The following table identifies the number of meetings the Board of\nTrustees and each committee held during the fiscal period ended July 31, 2026:

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

	NUMBER\n OF \n MEETINGS DURING \n FISCAL PERIOD \n ENDED July 31, 2026
Board		8
Executive Committee		0
Audit Committee		4
Governance Committee		3
Dividend Committee		12
Valuation Committee		4

LEADERSHIP STRUCTURE AND QUALIFICATIONS OF THE BOARD OF TRUSTEES.\nThe Board of Trustees is responsible for oversight of the Trust. The Trust has engaged Calamos Advisors to manage a Fund on a day-to-day\nbasis. The Board of Trustees oversees Calamos Advisors and certain other principal service providers in the operations of the Fund. The\nBoard of Trustees is currently composed of ten members, eight of whom are non-interested trustees. The Board of Trustees meets in-person\nat regularly scheduled meetings four times throughout the year. In addition, the board may meet in-person or by telephone at special meetings\nor on an informal basis at other times. As described above, the Board of Trustees has established five standing committees — Audit,\nDividend, Executive, Governance and Valuation — and may establish ad hoc committees or working groups from time to time to assist\nthe Board of Trustees in fulfilling its oversight responsibilities. The non-interested trustees also have engaged independent legal counsel\nto assist them in fulfilling their responsibilities. Such independent legal counsel also serves as counsel to the Trust.

The chairman of the Board of Trustees is an “interested person”\nof the Trust (as such term is defined in the 1940 Act). The non-interested trustees have appointed a lead independent trustee. The lead\nindependent trustee serves as a liaison between Calamos Advisors and the non-interested trustees and leads the non-interested trustees\nin all aspects of their oversight of a Fund. Among other things, the lead independent trustee reviews and approves, with the chairman,\nthe agenda for each board and committee meeting and facilitates communication among the Trust’s non-interested trustees. The trustees\nbelieve that the board’s leadership structure is appropriate given the characteristics and circumstances of the Trust. The trustees\nalso believe that this structure facilitates the exercise of the board’s independent judgment in fulfilling its oversight function\nand efficiently allocates responsibility among committees.

The Board of Trustees has concluded that, based on each trustee’s\nexperience, qualifications, attributes or skills on an individual basis and in combination with those of the other trustees, each trustee\nshould serve as a member of the board. In making this determination, the board has taken into account the actual service of the trustees\nduring their tenure in concluding that each should continue to serve. The board also has considered each trustee’s background and\nexperience. Set forth below is a brief discussion of the specific experience qualifications, attributes or skills of each trustee that\nled the board to conclude that he or she should serve as a trustee.

Each of Mses. Breen and Stuckey and Messrs. Calamos, Rybak,\nToub, and Wennlund has served for multiple years as a trustee of the Trust. In addition, each of Mses. Breen and Stuckey and Messrs. Armstrong,\nCalamos, Koudounis, Phlegar, Rybak, Toub, and Wennlund has more than 25 years of experience in the financial services industry.\nEach of Mses. Breen and Stuckey and Messrs. Calamos, Koudounis, Phlegar, Rybak, Toub, and Wennlund has experience serving on boards\nof other entities, including other investment companies. Each of Ms. Breen and Messrs. Calamos, Phlegar, Rybak, Toub, and Wennlund\nhas earned a Masters of Business Administration degree.

RISK OVERSIGHT. The operation of an ETF, including its investment\nactivities, generally involves a variety of risks. As part of its oversight of a Fund, the Board of Trustees oversees risk through various\nregular board and committee activities. The Board of Trustees, directly or through its committees, reviews reports from, among others,\nCalamos Advisors, the Trust’s Compliance Officer, the Trust’s independent registered public accounting firm, outside legal\ncounsel, and internal auditors of Calamos Advisors or its affiliates, as appropriate, regarding risks faced by a Fund and the risk management\nprograms Calamos Advisors and certain service providers. The actual day-to-day risk management with respect to a Fund resides with Calamos\nAdvisors and other service providers to a Fund. Although the risk management policies of Calamos Advisors and the service providers are\ndesigned to be effective, there is no guarantee that they will anticipate or mitigate all risks. Not all risks that may affect a Fund\ncan be identified, eliminated or mitigated and some risks simply may not be anticipated or may be beyond the control of the Board of Trustees\nor Calamos Advisors, its affiliates or other service providers.

TRUSTEE AND OFFICER COMPENSATION. John P. Calamos, Sr.\nand John Koudounis, the trustees who are an “interested person” of the Trust, do not receive compensation from the Trust.\nAlthough they are compensated, the non-interested trustees do not receive any pension or retirement benefits from the Trust. Mr. Kelly\nis the only Trust officer who receives compensation from the Trust. The following table sets forth the total compensation (including\nany amounts deferred, as described below) paid by the Trust during the periods indicated to each of the current trustees and officers\ncompensated by the Trust. As the Fund was not in operation as of the date of this SAI, no Trustee received any compensation from the\nFund during that time.

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

	Estimated		Total
	Compensation		Compensation
	from the Fund		from Calamos
	Fiscal Year		Funds Complex
Name	ending\n 7/31/27		8/1/25-7/31/26
John P. Calamos, Sr.	$	-		$	-
John S. Koudounis	$	-		$	-
Hugh P. Armstrong	$	1,040		$	192,203
Virginia G. Breen	$	1,082		$	241,083
Jeffrey S. Phlegar	$	1,040		$	192,203
William R. Rybak	$	418		$	247,583
Karen L. Stuckey	$	1,115		$	231,083
Christopher M. Toub	$	1,258		$	296,658
Lloyd A. Wennlund	$	1,082		$	241,083
Walter M. Kelly	$	3,247		$	571,017

(1) Compensation to be paid to the Independent Trustees for\nthe Fund’s initial fiscal year ending July 31, 2027.

(2)  Calamos Funds Complex consisted of 72 portfolios\nas of the end of the period indicated.

(3) Total compensation from the Calamos Funds Complex includes\ncompensation received in the aggregate from the Calamos Aksia Alternative Credit and Income Fund, Calamos Aksia Private Equity and Alternatives\nFund, and Calamos Aksia Hedged Strategies Fund in the amount of $45,575. Such compensation is subject to a different compensation schedule\nand allocation.

* Messrs. Armstrong, Koudounis, and Phlegar were elected to the\nBoard effective September 1, 2025.

The compensation paid to the non-interested trustees of Calamos Funds\nfor their services as such consists of an annual retainer fee in the amount of $230,000 (increased on January 1, 2026 from $210,000),\nwith annual supplemental retainers of $40,000 to the lead independent trustee, $20,000 to the chair of the audit committee and $10,000\nto the chair of any other committee. Each non-interested trustee receives a meeting attendance fee of $7,000 for any special board meeting\nattended in person or $3,500 for any special board meeting attended by telephone.

Compensation paid to the non-interested trustees is allocated among\nthe series of the Calamos Funds in accordance with a procedure determined from time to time by the board.

The Trust has adopted a deferred compensation plan for non-interested\ntrustees (the “Plan”). Under the Plan, a trustee who is not an “interested person” of Calamos Advisors and has\nelected to participate in the Plan (a “participating trustee”) may defer receipt of all or a portion of his or her compensation\nfrom the Trust in order to defer payment of income taxes or for other reasons. The deferred compensation payable to the participating\ntrustee is credited to the trustee’s deferred compensation account as of the business day such compensation otherwise would have\nbeen paid to the trustee. The value of a trustee’s deferred compensation account at any time is equal to what the value would be\nif the amounts credited to the account had instead been invested in shares of one or more of the Funds as designated by the trustee. Thus,\nthe value of the account increases with contributions to the account or with increases in the value of the measuring shares, and the value\nof the account decreases with withdrawals from the account or with declines in the value of the measuring shares. If a participating trustee\nretires, the trustee may elect to receive payments under the plan in a lump sum or in equal annual installments over a period of five\nyears. If a participating trustee dies, any amount payable under the Plan will be paid to the trustee’s beneficiaries. A Fund’s\nobligation to make payments under the Plan is a general obligation of that Fund. No Fund is liable for any other Fund’s obligations\nto make payments under the Plan.

The Fund had not yet publicly offered any Fund Shares for sale\nas of December 31, 2025. Accordingly, no trustee owned “beneficially” (within the meaning of that term as defined in\nRule 16a-1(a)(2) under the 1934 Act) any Fund Shares of the Fund as of December 31, 2025. As of December 31, 2025,\neach trustee beneficially owned (as determined pursuant to Rule 16a-1(a)(2) under the Securities Exchange Act of 1934, as amended\n(“1934 Act”)) Fund Shares of all funds in a Fund Complex having values within the indicated dollar ranges.* Mr. Armstrong\nand Mr. Phlegar, who were elected trustees of the Trust effective September 1, 2025, did not beneficially own shares of any\nFund as of December 31, 2025.

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

		AGGREGATE \nDOLLAR \nRANGE \nOF SHARES OF \nALL \nFUNDS \nIN THE FUND \nCOMPLEX
John P. Calamos, Sr.⁽¹⁾		Over $100,000
John S. Koudounis ⁽²⁾		Over $100,000
Hugh Armstrong ⁽²⁾		None
Virginia G. Breen		Over $100,000
Jeffrey Phlegar ⁽²⁾		None
William R. Rybak		Over $100,000
Karen L. Stuckey		Over $100,000
Christopher M. Toub		Over $100,000
Lloyd A. Wennlund		Over $100,000

(1)  Pursuant to Rule 16a-1(a)(2) of the 1934\nAct, John P. Calamos, Sr. may be deemed to have indirect beneficial ownership of Fund shares held by Calamos Investments LLC, its\nsubsidiaries, and its parent companies (Calamos Asset Management, Inc. and Calamos Partners LLC, and its parent company Calamos Family\nPartners, Inc.) due to his direct or indirect ownership interest in those entities. As a result, these amounts reflect any holdings\nof those entities in addition to the individual, personal accounts of John P. Calamos, Sr.

(2) Messrs. Armstrong, Koudounis, and Phlegar were elected\nto the Board effective September 1, 2025.

*  Valuation as of December 31, 2025.

CODE OF ETHICS. Personnel of Calamos Advisors and Calamos Financial\nServices LLC (“CFS”), the Fund’s distributor, are permitted to make personal securities transactions, including transactions\nin securities that the Trust may purchase, sell or hold, subject to requirements and restrictions set forth in the Code of Ethics of the\nTrust and the Code of Ethics of Calamos Advisors and CFS. The Codes of Ethics adopted pursuant to Rule 17j-1 under the 1940 Act contain\nprovisions and requirements designed to identify and address certain conflicts of interest between personal investment activities of Calamos\nAdvisors and CFS personnel and the interests of investment advisory clients such as the Trust. Among other things, the Codes of Ethics\nprohibit certain types of transactions absent prior approval, impose time periods during which personal transactions may not be made in\ncertain securities, and require the submission of duplicate broker confirmations and statements and quarterly reporting of securities\ntransactions. Additional restrictions apply to portfolio managers, traders, research analysts and others involved in the investment advisory\nprocess. Exceptions to these and other provisions of the Codes of Ethics may be granted in particular circumstances after review by appropriate\npersonnel.

Affiliates of Calamos Advisors and CFS, CAM, CILLC, Calamos Partners\nLLC (“CPL”), Calamos Family Partners, Inc. (“CFP”) and the owners of these affiliates, which include John\nP. Calamos, Sr. and members of his family (“Calamos Family”), may invest in products managed by Calamos Advisors to support\nthe continued growth of our investment products and strategies, including investments to seed new products. Notwithstanding any provision\nto the contrary in the Code of Ethics, investments and corresponding hedging transactions made by Calamos Advisors, CFS, CAM, CILLC, CPL,\nCFP and the Calamos Family in Calamos products (excluding Closed-End Funds and ETFs) are not subject to restrictions of the Code of Ethics,\nsuch as the short-term trading ban. However, these hedging transactions are subject to pre-clearance by the Corporate Investment Committee.\nCalamos Advisors’ CCO and Funds’ CCO are copied in the approval process. In addition, these entities do not receive preferential\ntreatment over clients. (They may, however, be traded together with discretionary client transactions.)

The General Counsel may approve additional strategies or instruments\nbased on unusual market circumstances and on the determination that the transactions would not impact the broader market or conflict with\nany customer activity.

PROXY VOTING PROCEDURES. The Fund has delegated proxy voting\nresponsibilities to Calamos Advisors, subject to the board of trustees’ general oversight. The Fund expects Calamos Advisors to\nvote proxies related to that Fund’s portfolio securities for which the Fund has voting authority consistent with the Fund’s\nbest interests. Calamos Advisors has adopted its own Proxy Voting Policies and Procedures (the “Policies”). The Policies\naddress, among other things, conflicts of interest that may arise between the Fund’s interests, and the interests of Calamos Advisors\nand its affiliates.

The following is a summary of the Policies used by Calamos Advisors\nin voting proxies.

To assist it in voting proxies, Calamos Advisors has established a\nProxy Review Committee (“committee”) comprised of representatives of its Portfolio Management (which may include portfolio\nmanagers and/or research analysts), Operations, and advisory, non-voting members from the Legal and Compliance Departments. The committee\nand/or its members will vote proxies using the following guidelines.

In general, if Calamos Advisors believes that a company’s management\nand board have interests sufficiently aligned with the Fund’s interest, Calamos Advisors will vote in favor of proposals recommended\nby the company’s management, including, but not by way of limitation, management’s recommendations on the election of directors\nbut will consider both meeting attendance and number of boards each board member sits on when determining its vote.

Because of the enormous variety and complexity of transactions that\nare presented to shareholders, such as mergers, acquisitions, reincorporations, reorganizations, shareholder rights plans, “poison\npills”, severance compensation packages, golden parachutes, that occur in a variety of industries, companies and market cycles,\nit is extremely difficult to foresee exactly what would be in the best interests of a Fund in all circumstances. Moreover, voting on such\nproposals involves considerations unique to each transaction. Accordingly, Calamos Advisors will vote on a case-by-case basis on proposals\npresenting these transactions.

Calamos Advisors has assigned its administrative duties with respect\nto the proxy analysis and voting decisions to the “Proxy Group” (the Investment team – research analysts and portfolio\nmanagement), and administrative processing to its Corporate Actions Group within the Operations Department. To assist it in analyzing\nproxies, Calamos subscribes to Glass Lewis, an unaffiliated third-party corporate governance research service that provides in-depth\nanalyses of shareholder meeting agendas and voting recommendations. Glass Lewis facilitates the voting of each proxy by applying Calamos’\ncustom proxy voting rules (“proxy voting policy”) to the proposal(s). Any proxy proposal that is not covered by the\nproxy voting guidelines is reviewed and considered by Calamos’ Proxy Group and voted in accordance with that review.

Finally, Calamos Advisors has established procedures to help identify\nand resolve conflicts of interest that might arise when voting proxies for the Funds. Calamos will generally apply its proxy voting policy\nto proxy proposals regardless of whether a conflict has been identified. However, in these situations, the Proxy Group will refer the\nproxy proposal, along with the recommended course of action, if any, to the Proxy Review Committee or a subcommittee thereof (each, a\n“committee”) for evaluation. The committee will independently review the proposals and determine the appropriate action to\nbe taken. The Corporate Actions Group will then memorialize the conflict(s) and the procedures used to address the conflict.

The Trust is required to file with the SEC on Form N-PX its complete\nproxy voting record for the 12-month period ending June 30, by no later than August 31 of each year. The Trust’s proxy\nvoting record for the most recent 12-month period ending June 30 will be available by August 31 of each year (1) on the\nSEC’s website at www.sec.gov, (2) on the Calamos Funds’ website at www.calamos.com, and (3) without charge, upon\nrequest, by calling 866.363.9219 or emailing caminfo@calamos.com.

You may obtain a copy of Calamos Advisors’ Policies by calling\n866.363.9219, by emailing caminfo@calamos.com, or by writing Calamos Advisors at: Calamos Investments, Attn: Client Services, 2020 Calamos\nCourt, Naperville, IL 60563, and on the SEC’s website at www.sec.gov.

DISCLOSURE OF PORTFOLIO HOLDINGS. The Trust has adopted a policy\nregarding the disclosure of information about the Trust’s portfolio holdings. The Board must approve all material amendments to\nthis policy. The Fund’s portfolio holdings are publicly disseminated each day the Fund is open for business through financial reporting\nand news services including publicly accessible Internet web sites. In addition, a basket composition file, which includes the security\nnames and share quantities to deliver in exchange for Fund Shares, together with estimates and actual cash components, is publicly disseminated\ndaily prior to the opening of the Exchange via the National Securities Clearing Corporation (“NSCC”). The basket represents\none Creation Unit of a Fund. The Trust and Calamos Advisors will not disseminate non-public information concerning the Trust.

Calamos Advisors and CFS carry out the policies and procedures governing\ndisclosure of portfolio security holdings, and as such have access to information regarding portfolio security holdings on a daily basis\nand may disclose that information to the Fund’s service providers and other third parties only in accordance with the policies and\nprocedures adopted by the Board of Trustees.

NON-PUBLIC DISCLOSURE

Disclosures required by Applicable Law. The Fund, Calamos Advisors\nand CFS may disclose portfolio security holdings information of a Fund as may be required by applicable law, rule, regulation or court\norder. Any officer of a Fund, Calamos Advisors or CFS is authorized to disclose portfolio security holdings pursuant to these policies\nand procedures.

As part of the Fund’s compliance program under Rule 38a-1\nunder the 1940 Act, the Trust’s Chief Compliance Officer periodically will review or cause to be reviewed portfolio security holding\ndisclosures in order to seek compliance with these policies and procedures. The Board of Trustees oversees disclosures through the reporting\nof the Chief Compliance Officer.

The Fund, Calamos Advisors and CFS do not receive compensation or other\nconsideration for the disclosure of portfolio security holdings.

CONTROL PERSONS AND PRINCIPAL HOLDERS OF SECURITIES

A principal shareholder is any person who owns (either of record or\nbeneficially) 5% or more of the outstanding Shares of a Fund. A control person is one who owns, either directly or indirectly, more than\n25% of the voting securities of a company or acknowledges the existence of control.

INVESTMENT ADVISORY SERVICES

Investment Adviser

Investment management and certain other services are provided to\nthe Trust by Calamos Advisors pursuant to a Management Agreement (the “Management Agreement”) dated January 10, 2023,\nas amended. Calamos Advisors also furnishes office space, equipment and management personnel to the Trust.

The Fund pays Calamos Advisors a fee based on its average daily\nnet assets that is accrued daily and paid on a monthly basis.

The Fund pays a fee on its average daily net assets at the annual\nrate of 0.74% on average daily net assets.

With respect to a Fund in the Calamos Family of Funds (each an “Acquiring\nFund”) that invests in Fund Shares of Calamos ETF, Calamos Advisors agrees to waive an amount equal to the portion of the advisory\nfee payable to the Fund that is attributable to the Acquiring Fund’s investment in the Fund, based on daily net assets. In the event\nthe Calamos ETF invests in another affiliated fund (the “Acquired Fund”), the portion of the Calamos ETF’s Investment\nManagement Fee equal to the advisory fee payable to the Acquired Fund (based on average daily net assets invested) is waived.

The Fund is advised by Calamos Advisors LLC (“Calamos Advisors”\nor the “Adviser”), 2020 Calamos Court, Naperville, Illinois 60563. Calamos Advisors, an investment adviser registered\nwith the SEC effective May 29, 1987, is a wholly owned subsidiary of Calamos Investments LLC (“CILLC”). Calamos Partners\nLLC (“CPL”) is the sole manager of CILLC. As of June 23, 2026, approximately 78% of the outstanding interests of CILLC\nwas owned by CPL, 22% by Calamos Asset Management, Inc. (“CAM”), and 0.04% by Calamos Equity Partners LLC (“CEP”).\nJohn P. Calamos, Sr. controls CILLC and the Adviser through his controlling interest in both CPL and CAM through the John P. Calamos\nQTIP Trust, an irrevocable trust with Mr. Calamos as sole trustee and investment adviser. John S. Koudounis is the other owner\nof both CAM and CPL. CEP is owned by John S. Koudounis and Daniel L. Dufresne.

John P. Calamos, Sr., is an affiliated person of the Fund\nand Calamos Advisors by virtue of his position as Chairman, Trustee and President of the Trust and Chairman and Global Chief Investment\nOfficer (“Global CIO”) of Calamos Advisors. John S. Koudounis, Thomas P. Kiley, Thomas E. Herman, Erik D. Ojala, Stephen\nAtkins, Daniel Dufresne and Walter Kelly are affiliated persons of the Fund and Calamos Advisors by virtue of their positions as Trustee\nand Vice President; Vice President; Vice President and Chief Financial Officer; Vice President and Secretary; Treasurer; Vice President;\nand Chief Compliance Officer of the Trust; respectively, and as President and Chief Executive Officer; Senior Vice President and Chief\nDistribution Officer; Executive Vice President and Chief Financial Officer; Senior Vice President, General Counsel and Secretary; Senior\nVice President and Head of Fund Administration; Executive Vice President and Chief Operating Officer; and Chief Compliance Officer of\nCalamos Advisors, respectively.

The use of the name “Calamos” in the name of the Trust\nand in the name of the Funds are pursuant to licenses granted by Calamos Investments LLC, and the Trust has agreed to change the names\nto remove those references if Calamos Advisors ceases to act as Adviser to the Funds.

EXPENSES

Out of its management fee, the Adviser pays substantially all expenses\nof the Fund, including the cost of transfer agency, custody, fund administration, legal, audit and other service and license fees, except\nfor distribution and service fees payable pursuant to a Rule 12b-1 plan, if any, acquired fund fees and expenses brokerage commissions\nand other expenses connected with the execution of portfolio transactions, taxes, interest, and extraordinary expenses.

Fees and expenses related to a Fund’s organization and registration\nand qualification of a Fund and its Fund Shares under federal and state securities laws will be borne by the Adviser.

MANAGEMENT APPROACH

Calamos Advisors employs a “team of teams” approach to\nportfolio management, led by the Global CIO and our CIO team consisting of five (5) Co-CIOs with specialized areas of investment\nexpertise. The Global CIO and Co-CIO team are responsible for oversight of investment team resources, investment processes, performance\nand risk. As heads of investment verticals, Co-CIOs manage investment team members and, along with Co-Portfolio Managers and Associate\nPortfolio Managers, have day-to-day portfolio oversight and construction responsibilities of their respective investment strategies. While\ninvestment research professionals within each Co-CIO’s team are assigned specific strategy responsibilities, they also provide support\nto other investment team verticals, creating deeper insights across a wider range of investment strategies. The combination of specialized\ninvestment teams with cross-team collaboration results in what we call our team of teams approach.

This team of teams approach is further reflected in the composition\nof Calamos Advisors’ Investment Committee, made up of the Global CIO, the Co-CIO team, and the Global Head of Trading. Other members\nof the investment team participate in Investment Committee meetings in connection with specific investment-related issues or topics as\ndeemed appropriate.

The structure and composition of the Investment Committee results in\na number of benefits, as it:

●   Leads to broader perspective on investment decisions:\nmultiple viewpoints and areas of expertise feed into consensus;

●   Promotes collaboration between teams; and

●   Functions as a think tank with the goal of identifying\nways to outperform the market on a risk-adjusted basis.

The objectives of the Investment Committee are to:

●   Form the firm’s top-down macro view,\nmarket direction, asset allocation, and sector/country positioning.

●   Establish firm-wide secular and cyclical themes\nfor review.

●   Review firm-wide and portfolio risk metrics,\nrecommending changes where appropriate.

●   Review firm-wide, portfolio and individual security\nliquidity constraints.

●   Evaluate firm-wide and portfolio investment performance.

●   Evaluate firm-wide and portfolio hedging policies\nand execution.

●   Evaluate enhancements to the overall investment\nprocess.

Shaheen Iqubal and Jordan Rosenfeld are the Fund’s portfolio\nmanagers and are collectively referred to within this registration statement as “Portfolio Managers”. The Portfolio Managers\nhave responsibility for allocating the portfolio across the market capitalization spectrum, sectors, and geographies within the portfolio’s\neligible investment universe and for reviewing the overall composition of the portfolio to ensure compliance with its stated investment\nobjective. The Portfolio Managers, in collaboration with other members of the Calamos Advisors investment teams, have the responsibility\nof overseeing the integration of the Fund’s investment approach and framework to ensure compliance with the Fund’s stated\ninvestment approach.

The Portfolio Managers also have responsibility for the day-to-day\nmanagement of accounts other than a Fund. Information regarding these other accounts as of July 31, 2026 is set forth below.

Other Accounts Managed and Assets by Account Type as of July 31,\n2026

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

	Registered \n Investment Companies		Other\n Pooled Investment Vehicles		Other\n Accounts
	Accounts		Assets		Accounts	Assets	Accounts		Assets
Jordan Rosenfeld		40		3,447,322,349		1		3,871,684		0	-
Shaheen Iqubal		6		2,727,296,183		0		-		0	-

Number of Accounts and Assets for which Advisory Fee is Performance\nBased as of July 31, 2026

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

	Registered \n Investment Companies		Other\n Pooled Investment Vehicles		Other\n Accounts
	Accounts		Assets		Accounts	Assets	Accounts		Assets
Jordan Rosenfeld		0		-		0		-		0	-
Shaheen Iqubal		0		-		0		-		0	-

The Portfolio Managers may invest for their own benefit in securities\nheld in brokerage and fund accounts. The information shown in the table does not include information about those accounts where the Portfolio\nManagers or members of their family have a beneficial or pecuniary interest because no advisory relationship exists with Calamos Advisors\nor any of its affiliates.

The Fund’s Portfolio Managers are responsible for managing both\nthe Fund and other accounts, including separate accounts.

Other than potential conflicts between investment strategies, the side-by-side\nmanagement of both a Fund and other accounts may raise potential conflicts of interest due to the interest held by Calamos Advisors in\nan account and certain trading practices used by the Portfolio Managers (e.g., cross trades between a Fund and another account and allocation\nof aggregated trades).

Calamos Advisors has developed policies and procedures reasonably designed\nto mitigate those conflicts. For example, Calamos Advisors will only place cross-trades in securities held by a Fund in accordance with\nthe rules promulgated under the 1940 Act and has adopted policies designed to ensure the fair allocation of securities purchased\non an aggregated basis. The allocation methodology employed by Calamos Advisors varies depending on the type of securities sought to be\nbought or sold and the type of client or group of clients. Generally, however, orders are placed first for those clients that have given\nCalamos Advisors brokerage discretion (including the ability to step out a portion of trades), and then to clients that have directed\nCalamos Advisors to execute trades through a specific broker. However, if the directed broker allows Calamos Advisors to execute with\nother brokerage firms, which then book the transaction directly with the directed broker, the order will be placed as if the client had\ngiven Calamos Advisors full brokerage discretion. Calamos Advisors and its affiliates frequently use a “rotational” method\nof placing and aggregating client orders and will build and fill a position for a designated client or group of clients before placing\norders for other clients.

A client account may not receive an allocation of an order if: (a) the\nclient would receive an unmarketable amount of securities based on account size; (b) the client has precluded Calamos Advisors from\nusing a particular broker; (c) the cash balance in the client account will be insufficient to pay for the securities allocated to\nit at settlement; (d) current portfolio attributes make an allocation inappropriate; and (e) account specific guidelines, objectives\nand other account specific factors make an allocation inappropriate. Allocation methodology may be modified when strict adherence to the\nusual allocation is impractical or leads to inefficient or undesirable results. Calamos Advisors’ head trader must approve each\ninstance that the usual allocation methodology is not followed and provide a reasonable basis for such instances and all modifications\nmust be reported in writing to Calamos Advisors’ Chief Compliance Officer on a monthly basis. Investment opportunities for which\nthere is limited availability generally are allocated among participating client accounts pursuant to an objective methodology (i.e.,\neither on a pro rata basis or using a rotational method, as described above). However, in some instances, Calamos Advisors may consider\nsubjective elements in attempting to allocate a trade, in which case a Fund may not participate, or may participate to a lesser degree\nthan other clients, in the allocation of an investment opportunity. In considering subjective criteria when allocating trades, Calamos\nAdvisors is bound by its fiduciary duty to its clients to treat all client accounts fairly and equitably.

As of September 30, 2026, Messrs. Iqubal and Rosenfeld\nreceive all of their compensation from Calamos Advisors. Compensation for portfolio management team members includes a competitive base\nsalary, and an annual cash bonus (driven by investment, company, and individual performance). Portfolio managers are also eligible for\nCalamos Advisors’ Long-Term Incentive (“LTI”) program, which is an incentive award vesting over time that reflects\nappreciation and depreciation in the value of both the funds managed by such professional and the company generally. LTI awards vest\non a three-year schedule (25% on or about the first anniversary of the award grant, 25% on or about the second anniversary of the award\ngrant, and 50% on or about the third anniversary of the award grant). Each investment team LTI award will be allocated as follows: (i) 33.3%\nto track the value of the associate’s managed strategies, (ii) 33.3% to track the Calamos strategy of the associate’s\nchoice, and (iii) 33.3% to track the value of the firm; all over the vesting period.

The existence of these separate asset or fee-based payments could create\na conflict of interest with regard to each portfolio manager’s allocation of investment opportunities among the accounts for which\nthey act as portfolio manager. Calamos Advisors maintains policies and procedures reasonably designed to mitigate such conflicts of interest.

This compensation structure considers annually the performance of the\nvarious strategies managed by the Portfolio Managers, among other factors, including, without limitation, the overall performance of the\nfirm. The Fund had not yet publicly offered any Fund Shares for sale prior to the date of this SAI. Accordingly, the Portfolio Managers\ndo not own any Fund Shares as of the date of this SAI.

DISTRIBUTOR

The Fund’s distributor is Calamos Financial Services LLC\n(“CFS” or the “Distributor”), 2020 Calamos Court, Naperville, Illinois, 60563. The Distributor has entered\ninto a distribution agreement (the “Distribution Agreement”) with the Trust pursuant to which it distributes Fund Shares.

Fund Shares will be continuously offered for sale by the Trust through\nthe Distributor only in Creation Units, as described below under “Transactions in Creation Units.” Fund Shares in less than\nCreation Units are not distributed by the Distributor. The Distributor also acts as agent for the Trust. The Distributor will deliver\na Prospectus to persons purchasing Fund Shares in Creation Units and will maintain records of both orders placed with it and confirmations\nof acceptance furnished by it. The Distributor is a broker-dealer registered under the 1934 Act and a member of the Financial Industry\nRegulatory Authority, Inc.

The Distributor has no role in determining the investment policies\nof the Fund, or which securities are to be purchased or sold by the Fund.

12b-1 Plan. The Board has adopted a distribution and service\nplan (“Distribution and Service Plan”) pursuant to Rule 12b-1 under the Investment Company Act (“Plan”).\nIn accordance with its Plan, a Fund is authorized to pay an amount up to 0.25% of its average daily net assets each year for certain\ndistribution-related activities. In addition, if the payment of management fees by a Fund is deemed to be indirect financing by the Fund\nof the distribution of its Fund Shares, such payment is authorized by the Plan. Calamos Advisors may use management fee revenue, as well\nas past profits or other resources, to pay for expenses incurred in connection with providing services intended to result in the sale\nof Fund Shares. Calamos Advisors may pay amounts to third parties for distribution or marketing services on behalf of a Fund.

The Plan was adopted in order to permit the implementation of a Fund’s\nmethod of distribution. No fees are currently paid by a Fund under the Plan, however, and there are no current plans to impose such fees.\nIn the event such fees were to be charged, over time they would increase the cost of an investment in a Fund because they would be paid\non an ongoing basis. If fees were charged under the Plan, the Trustees would receive and review at the end of each quarter a written report\nprovided by the Distributor of the amounts expended under the Plan and the purpose for which such expenditures were made.

The Plan will remain in effect for a period of one year and is\nrenewable from year to year with respect to a Fund, so long as its continuance is approved at least annually (1) by the vote of\na majority of the Trustees and (2) by a vote of the majority of the independent trustees, cast in person at a meeting called for\nthe purpose of voting on such approval. The Plan may not be amended to increase materially the amount of fees paid by a Fund unless such\namendment is approved by majority vote of the outstanding Fund Shares and by the independent trustees in the manner described above.\nThe Plan is terminable with respect to a Fund at any time by a vote of a majority of the independent trustees or by 1940 Act majority\nvote of the outstanding Fund Shares.

OTHER COMPENSATION TO INTERMEDIARIES

Calamos Advisors and its affiliates are currently subject to supplemental\ncompensation payment requests by certain securities broker-dealers, banks or other intermediaries, including third party administrators\nof qualified plans (each an “Intermediary”) whose customers have purchased Fund Shares. In their discretion, Calamos Advisors\nand its affiliates may make payments to an Intermediary for various purposes. These payments do not increase the amount paid by you or\na Fund, as they are paid from the legitimate profits from these entities in what is generally referred to as “revenue sharing.”

Revenue sharing payments are generally a percentage of the account’s\naverage annual net assets. Calamos Advisors and its affiliates may make these payments to an Intermediary for various purposes, including\nto help defray costs incurred by the Intermediary to educate financial advisers about a Fund so they can make recommendations and provide\nservices that are suitable and meet shareholder needs, to access the Intermediary’s representatives, to provide marketing support\nand other specified services. To the extent that a Fund does not pay for these costs directly, Calamos Advisors and its affiliates may\nalso make payments to certain financial intermediaries for administrative services such as record keeping, sub-accounting for shareholder\naccounts, client account maintenance support, statement preparation, transaction processing, payment of ticket charges per purchase or\nexchange order placed by a financial intermediary, payment of networking fees in connection with certain trading systems, or one-time\npayments for services such as setting up a Fund on a intermediary’s trading system.

In addition, Calamos Advisors and its affiliates may also share certain\nmarketing expenses with intermediaries, or pay for or sponsor informational meetings, seminars, client awareness events, support for marketing\nmaterials, sales reporting, or business building programs for such financial intermediaries to raise awareness of a Fund. Calamos Advisors\nand its affiliates may make payments to participate in intermediary marketing support programs which may provide Calamos Advisors, as\napplicable, with one or more of the following benefits: attendance at sales conferences, participation in meetings or training sessions,\naccess to or information about intermediary personnel, use of an intermediary’s marketing and communication infrastructure, fund\nanalysis tools, data and data analytics, business planning and strategy sessions with intermediary personnel, information on industry-\nor platform specific developments, trends and service providers, and other marketing-related services. Such payments may be in addition\nto, or in lieu of, the payments described above. These payments are intended to promote the sales of the Fund and to reimburse financial\nintermediaries, directly or indirectly, for the costs that they or their salespersons incur in connection with educational seminars, meetings,\nand training efforts about the Fund to enable the intermediaries and their salespersons to make suitable recommendations, provide useful\nservices, and maintain the necessary infrastructure to make the Fund available to their customers.

These payments may provide Intermediaries with an incentive to favor\nShares of a Fund over sales of shares of other ETFs or non-ETF investments. These payments may influence the Intermediary and your salesperson\nto recommend a Fund over another investment. Ask your salesperson or visit your Intermediary’s website for more information. You\nmay wish to take such payment arrangements into account when considering and evaluating any recommendations relating to Fund Shares and\nyou should discuss this matter with your Intermediary and its representatives. A Fund may utilize an Intermediary that offers and sells\nFund Shares to execute portfolio transactions for the Fund. The Fund and Calamos Advisors do not consider sales of Fund Shares as a factor\nin the selection of broker-dealers to execute portfolio transactions for a Fund.

PORTFOLIO TRANSACTIONS

Calamos Advisors is responsible for decisions to buy and sell securities\nfor a Fund, the selection of brokers and dealers to effect the transactions and the negotiation of prices and any brokerage commissions\non such transactions.

Portfolio transactions on behalf of a Fund effected on stock exchanges\ninvolve the payment of negotiated brokerage commissions. There is generally no stated commission in the case of securities traded in the\nOTC markets, but the price a Fund pays usually includes an undisclosed dealer commission or mark-up. For securities purchased in an underwritten\noffering, the price a Fund pays includes a disclosed, fixed commission or discount retained by the underwriter or dealer.

In executing portfolio transactions, Calamos Advisors uses its best\nefforts to obtain for a Fund the most favorable combination of price and execution available. In seeking the most favorable combination\nof price and execution, Calamos Advisors considers all factors it deems relevant, including price, the size of the transaction, the nature\nof the market for the security, the amount of commission, the timing of the transaction taking into account market prices and trends,\nthe execution capability of the broker-dealer and the quality of service rendered by the broker-dealer in other transactions.

In allocating a Fund’s portfolio brokerage transactions to unaffiliated\nbroker-dealers, Calamos Advisors may take into consideration the research, analytical, statistical and other information and services\nprovided by the broker-dealer, such as general economic reports and information, reports or analyses of particular companies or industry\ngroups, market timing and technical information, and the availability of the brokerage firm’s analysts for consultation. Although\nCalamos Advisors believes these services have substantial value, they are considered supplemental to Calamos Advisors’ own efforts\nin performing its duties under the Management Agreement.

Calamos Advisors does not guarantee any broker the placement of a predetermined\namount of securities transactions in return for the research or brokerage services it provides. Calamos Advisors does, however, have internal\nprocedures for allocating transactions in a manner consistent with its execution policies to brokers that it has identified as providing\nresearch, research-related products or services, or execution-related services of a particular benefit to its clients. Calamos Advisors\nhas entered into client commission agreements (“CCAs”) with certain broker-dealers under which the broker-dealers may use\na portion of their commissions to pay third parties or other broker-dealers that provide Calamos Advisors with research or brokerage services,\nas permitted under Section 28(e) of the Exchange Act. CCAs allow Calamos Advisors to direct broker-dealers to pool commissions\nthat are generated from orders executed at that broker-dealer, and then periodically direct the broker-dealer to pay third parties or\nother broker-dealers for research or brokerage services. All uses of CCAs by Calamos Advisors are subject to applicable law and their\nbest execution obligations. Brokerage and research products and services furnished by brokers may be used in servicing any or all of the\nclients of Calamos Advisors and such research may not necessarily be used by Calamos Advisors in connection with the accounts which paid\ncommissions to the broker providing such brokerage and research products and services.

As permitted by Section 28(e) of the 1934 Act, Calamos Advisors\nmay pay a broker-dealer that provides brokerage and research services an amount of commission for effecting a securities transaction for\na Fund in excess of the commission that another broker-dealer would have charged for effecting that transaction if Calamos Advisors believes\nthe amount to be reasonable in relation to the value of the overall quality of the brokerage and research services provided. Other clients\nof Calamos Advisors may indirectly benefit from the availability of these services to Calamos Advisors, and a Fund may indirectly benefit\nfrom services available to Calamos Advisors as a result of research services received by Calamos Advisors through transactions for other\nclients. In addition, Calamos Advisors may execute portfolio transactions for a Fund, to the extent permitted by law, through broker-dealers\naffiliated with a Fund, Calamos Advisors, CFS, or other broker-dealers distributing Shares of a Fund if it reasonably believes that the\ncombination of price and execution is at least as favorable as with unaffiliated broker-dealers, and in such transactions any such broker-dealer\nwould receive brokerage commissions paid by a Fund.

In certain cases, Calamos Advisors may obtain products or services\nfrom a broker that have both research and non-research uses. Examples of non-research uses are administrative and marketing functions.\nThese are referred to as “mixed use” products. In each case, Calamos Advisors makes a good faith effort to determine the proportion\nof such products or services that may be used for research and non-research purposes. That determination is based upon the time spent\nby Calamos Advisors personnel for research and non-research uses. The portion of the costs of such products or services attributable to\nresearch usage may be defrayed by Calamos Advisors through brokerage commissions generated by transactions of its clients, including a\nFund. Calamos Advisors pays the provider in cash for the non-research portion of its use of these products or services.

Subject to applicable law, Calamos Advisors may select brokers\nthat furnish Calamos Advisors, the Funds, or other Calamos Advisors client accounts or personnel, directly or through correspondent relationships,\nwith research or other appropriate services which provide, in Calamos Advisors’ view, appropriate assistance to Calamos Advisors\nin the investment decision-making process (including with respect to futures, fixed-price offerings and OTC transactions). Such research\nor other services may include, to the extent permitted by law, research reports on companies, industries and securities; economic and\nfinancial data; financial publications; proxy analysis; trade industry seminars; computer databases; research-oriented software and other\nservices and products.

ADDITIONAL INFORMATION CONCERNING THE FUND SHARES

Organization and Description of Shares of Beneficial Interest

The Trust is a Delaware statutory trust and registered open-end investment\ncompany. The Trust was organized on June 17, 2013, and has authorized capital of unlimited Fund Shares of beneficial interest of\nno-par value that may be issued in more than one class or series. Currently, the Trust consists of forty-two actively managed series.\nThe Board of Trustees may designate additional series.

Under Delaware law, the Trust is not required to hold an annual shareholders’\nmeeting if the 1940 Act does not require such a meeting. Shareholders holding two-thirds of Fund Shares outstanding of the relevant Fund\nmay remove Trustees from office by votes cast at a meeting of Trust shareholders or by written consent.

All Fund Shares are freely transferable. Fund Shares will not have\npreemptive rights or cumulative voting rights, and none of the Fund Shares will have any preference to conversion, exchange, dividends,\nretirements, liquidation, redemption, or any other feature. Fund Shares have equal voting rights. The Trust Instrument confers upon the\nBoard the power, by resolution, to alter the number of Fund Shares constituting a Creation Unit or to specify that Fund Shares may be\nindividually redeemable. The Trust reserves the right to adjust the stock prices of Fund Shares to maintain convenient trading ranges\nfor investors. Any such adjustments would be accomplished through stock splits or reverse stock splits that would have no effect on the\nNAV of a Fund.

The Trust Instrument of the Trust disclaims liability of the shareholders\nor the officers of the Trust for acts or obligations of the Trust that are binding only on the assets and property of the Trust. The Trust\nInstrument provides for indemnification out of a Fund’s property for all loss and expense of a Fund’s shareholders being held\npersonally liable solely by reason of his or her being or having been a shareholder and not because of his or her acts or omissions or\nfor some other reason. The risk of a Trust shareholder incurring financial loss on account of shareholder liability is limited to circumstances\nin which a Fund itself would not be able to meet the Trust’s obligations and this risk should be considered remote.

If a Fund does not grow to a size to permit it to be economically viable,\na Fund may cease operations. In such an event, shareholders may be required to liquidate or transfer their Fund Shares at an inopportune\ntime and shareholders may lose money on their investment.

Book Entry Only System

The following information supplements, and should be read in conjunction\nwith, the section in the Prospectus entitled “Fund Facts — Book Entry.”

The Depository Trust Company (“DTC”) acts as Securities\nDepository for Fund Shares. Fund Shares are represented by securities registered in the name of DTC or its nominee and deposited with,\nor on behalf of, DTC.

DTC, a limited purpose trust company, was created to hold securities\nof its participants (the “DTC Participants”) and to facilitate the clearance and settlement of securities transactions among\nthe DTC Participants in such securities through electronic book entry changes in accounts of the DTC Participants, thereby eliminating\nthe need for physical movement of securities certificates. DTC Participants include securities brokers and dealers, banks, trust companies,\nclearing corporations and certain other organizations, some of whom (and/or their representatives) own DTC. More specifically, DTC is\nowned by a number of its DTC Participants and by NYSE and FINRA. Access to the DTC system is also available to others such as banks, brokers,\ndealers and trust companies that clear through or maintain a custodial relationship with a DTC Participant, either directly or indirectly\n(the “Indirect Participants”).

Beneficial ownership of Fund Shares is limited to DTC Participants, Indirect\nParticipants and persons holding interests through DTC Participants and Indirect Participants. Ownership of beneficial interests in Fund\nShares (owners of such beneficial interests are referred to herein as “Beneficial Owners”) is shown on, and the transfer of\nownership is effected only through, records maintained by DTC (with respect to DTC Participants) and on the records of DTC Participants\n(with respect to Indirect Participants and Beneficial Owners that are not DTC Participants). Beneficial Owners will receive from or through\nthe DTC Participant written confirmation relating to their purchase and sale of Fund Shares.

Conveyance of all notices, statements and other communications to Beneficial\nOwners is effected as follows. Pursuant to the Depositary Agreement between the Trust and DTC, DTC is required to make available to the\nTrust upon request and for a fee to be charged to the Trust a listing of the Fund Shares held by each DTC Participant. The Trust shall\ninquire of each such DTC Participant as to the number of Beneficial Owners holding Fund Shares, directly or indirectly, through such DTC\nParticipant. The Trust shall provide each such DTC Participant with copies of such notice, statement or other communication, in such form,\nnumber and at such place as such DTC Participant may reasonably request, in order that such notice, statement or communication may be\ntransmitted by such DTC Participant, directly or indirectly, to such Beneficial Owners. In addition, the Trust shall pay to each such\nDTC Participant a fair and reasonable amount as reimbursement for the expenses attendant to such transmittal, all subject to applicable\nstatutory and regulatory requirements.

Fund distributions shall be made to DTC or its nominee, Cede &\nCo., as the registered holder of all Fund Shares. DTC or its nominee, upon receipt of any such distributions, shall immediately credit\nDTC Participants’ accounts with payments in amounts proportionate to their respective beneficial interests in Fund Shares as shown\non the records of DTC or its nominee. Payments by DTC Participants to Indirect Participants and Beneficial Owners of Fund Shares held\nthrough such DTC Participants will be governed by standing instructions and customary practices, and will be the responsibility of such\nDTC Participants.

The Trust has no responsibility or liability for any aspect of the\nrecords relating to or notices to Beneficial Owners, or payments made on account of beneficial ownership interests in such Fund Shares,\nor for maintaining, supervising or reviewing any records relating to such beneficial ownership interests, or for any other aspect of the\nrelationship between DTC and the DTC Participants or the relationship between such DTC Participants and the Indirect Participants and\nBeneficial Owners owning through such DTC Participants.

DTC may decide to discontinue providing its service with respect to\nFund Shares at any time by giving reasonable notice to the Trust and discharging its responsibilities with respect thereto under applicable\nlaw. Under such circumstances, the Trust shall take action to find a replacement for DTC to perform its functions at a comparable cost.

The Trust is required to disclose on a quarterly basis the complete\nschedule of the Fund’s portfolio holdings with the SEC on Form N-PORT. Form N-PORT for the Trust is available on the SEC’s\nwebsite at https://www.sec.gov. A Fund’s Form N-PORT may also be reviewed and copied at the SEC’s Public Reference Room\nin Washington, D.C. and information on the operation of the Public Reference Room may be obtained by calling 1-800-SEC-0330. The Trust’s\nForms N-PORT are available without charge, upon request, by calling (866) 363-9219 or by writing to Calamos ETF Trust, 2020 Calamos Court,\nNaperville, IL 60563.

CREATION AND REDEMPTION OF CREATION UNITS

General

A Fund will issue and sell Fund Shares only in Creation Units on\na continuous basis, without an initial sales load, at their NAV next determined after receipt, on any Business Day (as defined herein),\nof an order in proper form. An Authorized Participant (defined below) that is not a “qualified institutional buyer,” as such\nterm is defined under Rule 144A of the Securities Act, will not be able to receive, as part of a redemption, restricted securities\neligible for resale under Rule 144A.

A “Business Day” with respect to a Fund is any day on which\nthe NYSE is open for business. As of the date of this SAI, the NYSE observes the following holidays: New Year’s Day, Martin Luther\nKing, Jr. Day, President’s Day (Washington’s Birthday), Good Friday, Memorial Day (observed), Juneteenth National Independence\nDay, Independence Day, Labor Day, Thanksgiving Day and Christmas Day.

Distribution of Fund Shares

In connection with its launch, a Fund was seeded through the sale of\none or more Creation Units to one or more initial investors. Initial investors participating in the seeding may be Authorized Participants\nor a lead market maker, other third-party investor or an affiliate of a Fund or the Adviser purchasing from an Authorized Participant.\nEach such initial investor may sell some or all of the Fund Shares underlying the Creation Unit(s) held by them pursuant to the registration\nstatement for a Fund (each, a “Selling Shareholder”), which Fund Shares have been registered to permit the resale from time\nto time after purchase. No Fund will receive any of the proceeds from the resale by the Selling Shareholders of these Fund Shares. Selling\nShareholders may sell Fund Shares owned by them directly or through broker-dealers, in accordance with applicable law, on any national\nsecurities exchange on which the Fund Shares may be listed or quoted at the time of sale, through trading systems, in the over-the-counter\nmarket or in transactions other than on these exchanges or systems at fixed prices, at prevailing market prices at the time of the sale,\nat varying prices determined at the time of sale, or at negotiated prices. These sales may be effected through brokerage transactions,\nprivately negotiated trades, block sales, entry into options or other derivatives transactions or through any other means authorized by\napplicable law. Selling Shareholders may redeem the Fund Shares held in Creation Unit size by them through an Authorized Participant.\nAny Selling Shareholder and any broker-dealer or agents participating in the distribution of Fund Shares may be deemed to be “underwriters”\nwithin the meaning of Section 2(a)(11) of the Securities Act, in connection with such sales. Any Selling Shareholder and any other\nperson participating in such distribution will be subject to any applicable provisions of the Exchange Act and the rules and regulations\nthereunder.

Fund Deposit

The consideration for purchase of a Creation Unit of a Fund generally\nconsists of the in-kind deposit of a designated portfolio of securities (the “Deposit Securities”) per each Creation Unit,\nand the Cash Component (defined below), computed as described below. The Trust reserves the right to permit or require the substitution\nof Deposit Cash to be added to the Cash Component to replace any Deposit Security. When accepting purchases of Creation Units for all\nor a portion of Deposit Cash, a Fund may incur additional costs associated with the acquisition of Deposit Securities that would otherwise\nbe provided by an in-kind purchaser.

Together, the Deposit Securities or Deposit Cash, as applicable, and\nthe Cash Component constitute the “Fund Deposit,” which represents the minimum initial and subsequent investment amount for\na Creation Unit of a Fund. The “Cash Component” is an amount equal to the difference between the NAV of Fund Shares (per Creation\nUnit) and the value of the Deposit Securities or Deposit Cash, as applicable. If the Cash Component is a positive number (i.e., the NAV\nper Creation Unit exceeds the value of the Deposit Securities or Deposit Cash, as applicable), the Cash Component shall be such positive\namount. If the Cash Component is a negative number (i.e., the NAV per Creation Unit is less than the value of the Deposit Securities or\nDeposit Cash, as applicable), the Cash Component shall be such negative amount and the creator will be entitled to receive cash in an\namount equal to the Cash Component. The Cash Component serves the function of compensating for any differences between the NAV per Creation\nUnit and the value of the Deposit Securities or Deposit Cash, as applicable. Computation of the Cash Component excludes any stamp duty\nor other similar fees and expenses payable upon transfer of beneficial ownership of the Deposit Securities, if applicable, which shall\nbe the sole responsibility of the Authorized Participant.

A Fund, through NSCC, make available on each Business Day, prior to\nthe opening of business on the Exchange (currently 9:30 a.m., Eastern Time), the list of the names and the required number of Fund Shares\nof each Deposit Security or the required amount of Deposit Cash, as applicable, to be included in the current Fund Deposit (based on information\nat the end of the previous Business Day) for a Fund. Such Fund Deposit is subject to any applicable adjustments as described below, to\neffect purchases of Creation Units of a Fund until such time as the next-announced composition of the Deposit Securities or the required\namount of Deposit Cash, as applicable, is made available.

The identity and number of Fund Shares of the Deposit Securities or\nthe amount of Deposit Cash, as applicable, required for a Fund Deposit for a Fund changes as rebalancing adjustments and corporate action\nevents are reflected from time to time by the Adviser with a view to the investment objective of a Fund.

The Trust reserves the right to permit or require the substitution\nof Deposit Cash to replace any Deposit Security, which shall be added to the Cash Component, including, without limitation, in situations\nwhere the Deposit Security: (i) may not be available in sufficient quantity for delivery; (ii) may not be eligible for transfer\nthrough the systems of DTC for corporate securities and municipal securities; (iii) may not be eligible for trading by an Authorized\nParticipant or the investor for which it is acting; (iv) would be restricted under the securities laws or where the delivery of the\nDeposit Security to the Authorized Participant would result in the disposition of the Deposit Security by the Authorized Participant becoming\nrestricted under the securities laws; or (v) in certain other situations (collectively, “custom orders”). The adjustments\ndescribed above will reflect changes known to the Adviser on the date of announcement to be in effect by the time of delivery of a Fund\nDeposit from certain corporate actions.

Procedures for Purchase of Creation Units

To be eligible to place orders with the Transfer Agent to purchase\na Creation Unit of a Fund, an entity must be (i) a “Participating Party” (i.e., a broker- dealer or other participant\nin the clearing process through the Continuous Net Settlement System of the NSCC (the “Clearing Process”)), a clearing agency\nthat is registered with the SEC; or (ii) a DTC Participant (see “Book Entry Only System”). In addition, each Participating\nParty or DTC Participant (each an “Authorized Participant”) must execute a Participant Agreement that has been agreed to by\nthe Distributor, and that has been accepted by the Transfer Agent, with respect to purchases and redemptions of Creation Units. Each Authorized\nParticipant will agree, pursuant to the terms of a Participant Agreement, on behalf of itself or any investor on whose behalf it will\nact, to certain conditions, including that it will pay to the Trust, an amount of cash sufficient to pay the Cash Component together with\nthe creation transaction fee (described below), if applicable, and any other applicable fees and taxes.

All orders to purchase Fund Shares directly from a Fund must be placed\nfor one or more Creation Units and in the manner and by the time set forth in the Participant Agreement and/or applicable order form.\nThe order cut-off time for a Fund for orders to purchase Creation Units is expected to be 2:00 p.m. Eastern Time which time may be\nmodified by a Fund from time-to-time by amendment to the Participant Agreement and/or applicable order form. In the case of custom orders,\nthe order must be received by the Transfer Agent no later than 2:30 p.m. Eastern Time or such earlier time as may be designated by\na Fund and disclosed to Authorized Participants. The date on which an order to purchase Creation Units (or an order to redeem Creation\nUnits, as set forth below) is received and accepted is referred to as the “Order Placement Date.”

An Authorized Participant may require an investor to make certain representations\nor enter into agreements with respect to the order (e.g., to provide for payments of cash, when required). Investors should be aware that\ntheir particular broker may not have executed a Participant Agreement and that, therefore, orders to purchase Fund Shares directly from\na Fund in Creation Units have to be placed by the investor’s broker through an Authorized Participant that has executed a Participant\nAgreement. In such cases there may be additional charges to such investor. At any given time, there may be only a limited number of broker-dealers\nthat have executed a Participant Agreement and only a small number of such Authorized Participants may have international capabilities.

On days when the Exchange closes earlier than normal, a Fund may require\norders to create Creation Units to be placed earlier in the day. In addition, if a market or markets on which a Fund’s investments\nare primarily traded is closed, a Fund will also generally not accept orders on such day(s). Orders must be transmitted by an Authorized\nParticipant by telephone or other transmission method acceptable to the Transfer Agent pursuant to procedures set forth in the Participant\nAgreement and in accordance with the applicable order form. On behalf of a Fund, the Transfer Agent will notify the Custodian of such\norder. The Custodian will then provide such information to the appropriate local sub-custodian(s). Those placing orders through an Authorized\nParticipant should allow sufficient time to permit proper submission of the purchase order to the Transfer Agent by the cut-off time on\nsuch Business Day. Economic or market disruptions or changes, or telephone or other communication failures may impede the ability to reach\nthe Transfer Agent or an Authorized Participant.

Fund Deposits must be delivered by an Authorized Participant through\nthe Federal Reserve System (for cash) or through DTC (for corporate securities), through a sub-custody agent (for foreign securities)\nand/or through such other arrangements allowed by the Trust or its agents. With respect to foreign Deposit Securities, the Custodian shall\ncause the sub-custodian of a Fund to maintain an account into which the Authorized Participant shall deliver, on behalf of itself or the\nparty on whose behalf it is acting, such Deposit Securities (or Deposit Cash for all or a part of such securities, as permitted or required),\nwith any appropriate adjustments as advised by the Trust. Foreign Deposit Securities must be delivered to an account maintained at the\napplicable local sub-custodian. A Fund Deposit transfer must be ordered by the Authorized Participant in a timely fashion so as to ensure\nthe delivery of the requisite number of Deposit Securities or Deposit Cash, as applicable, to the account of the applicable Fund or its\nagents by no later than 12:00 p.m. Eastern Time (or such other time as specified by the Trust) on the Settlement Date. If a Fund\nor its agents do not receive all of the Deposit Securities, or the required Deposit Cash in lieu thereof, by such time, then the order\nmay be deemed rejected and the Authorized Participant shall be liable to a Fund for losses, if any, resulting therefrom. The “Settlement\nDate” for a Fund is generally the second Business Day after the Order Placement Date. All questions as to the number of Deposit\nSecurities or Deposit Cash to be delivered, as applicable, and the validity, form and eligibility (including time of receipt) for the\ndeposit of any tendered securities or cash, as applicable, will be determined by the Trust, whose determination shall be final and binding.\nThe amount of cash represented by the Cash Component must be transferred directly to the Custodian through the Federal Reserve Bank wire\ntransfer system in a timely manner so as to be received by the Custodian no later than the Settlement Date. If the Cash Component and\nthe Deposit Securities or Deposit Cash, as applicable, are not received by the Custodian in a timely manner by the Settlement Date, the\ncreation order may be cancelled. Upon written notice to the Transfer Agent, such canceled order may be resubmitted the following Business\nDay using a Fund Deposit as newly constituted to reflect the then current NAV of the applicable Fund.

The order shall be deemed to be received on the Business Day on which\nthe order is placed provided that the order is placed in proper form prior to the applicable cut-off time and the federal funds in the\nappropriate amount are deposited by 2:00 p.m. or 3:00 p.m., Eastern Time (as set forth on the applicable order form), with the Custodian\non the Settlement Date. If the order is not placed in proper form as required, or federal funds in the appropriate amount are not received\nby 2:00 p.m. or 3:00 p.m., Eastern Time (as set forth on the applicable order form) on the Settlement Date, then the order may be\ndeemed to be rejected and the Authorized Participant shall be liable to a Fund for losses, if any, resulting therefrom. A creation request\nis considered to be in “proper form” if all procedures set forth in the Participant Agreement, order form and this SAI are\nproperly followed.

Issuance of a Creation Unit

Except as provided in this SAI, Creation Units will not be issued until\nthe transfer of good title to the Trust of the Deposit Securities or payment of Deposit Cash, as applicable, and the payment of the Cash\nComponent have been completed. When the sub-custodian has confirmed to the Custodian that the required Deposit Securities (or the cash\nvalue thereof) have been delivered to the account of the relevant sub-custodian or sub-custodians, the Transfer Agent and the Adviser\nshall be notified of such delivery, and the Trust will issue and cause the delivery of the Creation Units. The delivery of Creation Units\nso created generally will occur no later than the second Business Day following the day on which the purchase order is deemed received\nby the Transfer Agent. The Authorized Participant shall be liable to the applicable Fund for losses, if any, resulting from unsettled\norders.

Creation Units may be purchased in advance of receipt by the Trust\nof all or a portion of the applicable Deposit Securities as described below. In these circumstances, the initial deposit will have a value\ngreater than the NAV of Fund Shares on the date the order is placed in proper form since, in addition to available Deposit Securities,\ncash must be deposited in an amount equal to the sum of (i) the Cash Component, plus (ii) an additional amount of cash equal\nto up to 115% of the market value of the undelivered Deposit Securities (the “Additional Cash Deposit”), which shall be maintained\nin a separate non-interest bearing collateral account. The Authorized Participant must deposit with the Custodian the Additional Cash\nDeposit, as applicable, by 12:00 p.m. Eastern Time (or such other time as specified by the Trust) on the Settlement Date. If a Fund\nor its agents do not receive the Additional Cash Deposit in the appropriate amount, by such time, then the order may be deemed rejected\nand the Authorized Participant shall be liable to a Fund for losses, if any, resulting therefrom. An additional amount of cash shall be\nrequired to be deposited with the Trust, pending delivery of the missing Deposit Securities to the extent necessary to maintain the Additional\nCash Deposit with the Trust in an amount at least equal to the applicable percentage, as set forth in the Participant Agreement, of the\ndaily market value of the missing Deposit Securities. The Participant Agreement will permit the Trust to buy the missing Deposit Securities\nat any time. Authorized Participants will be liable to the Trust for the costs incurred by the Trust in connection with any such purchases.\nThese costs will be deemed to include the amount by which the actual purchase price of the Deposit Securities exceeds the value of such\nDeposit Securities on the day the purchase order was deemed received by the Transfer Agent plus the brokerage and related transaction\ncosts associated with such purchases.

The Trust will return any unused portion of the Additional Cash Deposit\nonce all of the missing Deposit Securities have been properly received by the Custodian or purchased by the Trust and deposited into the\nTrust. In addition, a transaction fee, as described below under “Creation Transaction Fee,” may be charged. The delivery of\nCreation Units so created generally will occur no later than the Settlement Date.

Acceptance of Orders of Creation Units

The Trust reserves the right to reject an order for Creation Units\ntransmitted to it by the Transfer Agent with respect to a Fund including, without limitation, if (a) the order is not in proper form;\n(b) the Deposit Securities or Deposit Cash, as applicable, delivered by the Participant are not as disseminated through the facilities\nof the NSCC for that date by the Custodian; (c) the investor(s), upon obtaining Fund Shares ordered, would own 80% or more of the\ncurrently outstanding Fund Shares; (d) the acceptance of a Fund Deposit would, in the opinion of counsel, be unlawful; (e) the\nacceptance or receipt of the order for a Creation Unit would, in the opinion of counsel to the Trust, be unlawful; or (f) in the\nevent that circumstances outside the control of the Trust, the Custodian, the Transfer Agent and/or the Adviser make it for all practical\npurposes not feasible to process orders for Creation Units.

Examples of such circumstances include acts of God or public service\nor utility problems such as fires, floods, extreme weather conditions and power outages resulting in telephone, telecopy and computer\nfailures; market conditions or activities causing trading halts; systems failures involving computer or other information systems affecting\nthe Trust, the Distributor, the Custodian, a sub-custodian, the Transfer Agent, DTC, NSCC, Federal Reserve System, or any other participant\nin the creation process, and other extraordinary events. The Transfer Agent shall notify a prospective creator of a Creation Unit and/or\nthe Authorized Participant acting on behalf of the creator of a Creation Unit of its rejection of the order of such person. The Trust,\nthe Transfer Agent, the Custodian, any sub-custodian and the Distributor are under no duty, however, to give notification of any defects\nor irregularities in the delivery of Fund Deposits nor shall either of them incur any liability for the failure to give any such notification.\nThe Trust, the Transfer Agent, the Custodian and the Distributor shall not be liable for the rejection of any purchase order for Creation\nUnits.

All questions as to the number of Fund Shares of each security in the\nDeposit Securities and the validity, form, eligibility and acceptance for deposit of any securities to be delivered shall be determined\nby the Trust, and the Trust’s determination shall be final and binding.

Creation Transaction Fee

A fixed purchase (i.e., creation) transaction fee, payable to a Fund’s\ncustodian, may be imposed for the transfer and other transaction costs associated with the purchase of Creation Units (“Creation\nOrder Costs”). The standard fixed creation transaction fee for a Fund is $250 for in-kind Creation Units or $100 for cash Creation\nUnits, or such other amount as agreed to in writing between the parties, regardless of the number of Creation Units created in the transaction.\nA Fund may adjust the standard fixed creation transaction fee from time to time. The fixed creation fee may be waived on certain orders\nif a Fund’s custodian has determined to waive some or all of the Creation Order Costs associated with the order or another party,\nsuch as the Adviser, has agreed to pay such fee.

In addition, a variable fee, payable to a Fund, of up to a maximum\nof 2% of the value of the Creation Units subject to the transaction may be imposed for cash purchases, non-standard orders, or partial\ncash purchases of Creation Units. The variable charge is primarily designed to cover additional costs (e.g., brokerage, taxes) involved\nwith buying the securities with cash. A Fund may determine to not charge a variable fee on certain orders when the Adviser has determined\nthat doing so is in the best interests of Fund shareholders, e.g., for creation orders that facilitate the rebalance of a Fund’s\nportfolio in a more tax efficient manner than could be achieved without such order. Investors who use the services of a broker or other\nsuch intermediary may be charged a fee for such services. Investors are responsible for the fixed costs of transferring a Fund Securities\nfrom the Trust to their account or on their order.

Risks of Purchasing Creation Units

There are certain legal risks unique to investors purchasing Creation\nUnits directly from a Fund. Because Fund Shares may be issued on an ongoing basis, a “distribution” of Fund Shares could be\noccurring at any time. Certain activities that a shareholder performs as a dealer could, depending on the circumstances, result in the\nshareholder being deemed a participant in the distribution in a manner that could render the shareholder a statutory underwriter and subject\nto the prospectus delivery and liability provisions of the Securities Act. For example, a shareholder could be deemed a statutory underwriter\nif it purchases Creation Units from a Fund, breaks them down into the constituent Fund Shares, and sells those Fund Shares directly to\ncustomers, or if a shareholder chooses to couple the creation of a supply of new Fund Shares with an active selling effort involving solicitation\nof secondary-market demand for Fund Shares. Whether a person is an underwriter depends upon all of the facts and circumstances pertaining\nto that person’s activities, and the examples mentioned here should not be considered a complete description of all the activities\nthat could cause you to be deemed an underwriter.

Dealers who are not “underwriters” but are participating\nin a distribution (as opposed to engaging in ordinary secondary-market transactions), and thus dealing with Fund Shares as part of an\n“unsold allotment” within the meaning of Section 4(a)(3)(C) of the Securities Act, will be unable to take advantage\nof the prospectus delivery exemption provided by Section 4(a)(3) of the Securities Act.

Redemptions

Fund Shares may be redeemed only in Creation Units at their NAV next\ndetermined after receipt of a redemption request in proper form by a Fund through the Transfer Agent and only on a Business Day. Except\nupon liquidation of a Fund, the Trust will not redeem Fund Shares in amounts less than Creation Units. Investors must accumulate enough\nFund Shares in the secondary market to constitute a Creation Unit to have such Fund Shares redeemed by the Trust. There can be no assurance,\nhowever, that there will be sufficient liquidity in the public trading market at any time to permit assembly of a Creation Unit. Investors\nshould expect to incur brokerage and other costs in connection with assembling a sufficient number of Fund Shares to constitute a redeemable\nCreation Unit.

With respect to a Fund, the Custodian, through the NSCC, makes available\nprior to the opening of business on the Exchange (currently 9:30 a.m., Eastern Time) on each Business Day, the list of the names and Share\nquantities of a Fund’s portfolio securities that will be applicable (subject to possible amendment or correction) to redemption\nrequests received in proper form (as defined below) on that day (“Fund Securities”). Fund Securities received on redemption\nmay not be identical to Deposit Securities.

Redemption proceeds for a Creation Unit are paid either in-kind or\nin cash, or combination thereof, as determined by the Trust. With respect to in-kind redemptions of a Fund, redemption proceeds for a\nCreation Unit will consist of Fund Securities — as announced by the Custodian on the Business Day of the request for redemption\nreceived in proper form plus cash in an amount equal to the difference between the NAV of Fund Shares being redeemed, as next determined\nafter a receipt of a request in proper form, and the value of a Fund Securities (the “Cash Redemption Amount”), less a fixed\nredemption transaction fee, as applicable, as set forth below. In the event that the Fund Securities have a value greater than the NAV\nof Fund Shares, a compensating cash payment equal to the differential is required to be made by or through an Authorized Participant by\nthe redeeming shareholder. Notwithstanding the foregoing, at the Trust’s discretion, an Authorized Participant may receive the corresponding\ncash value of the securities in lieu of the in-kind securities value representing one or more Fund Securities.

Redemption Transaction Fee

A fixed redemption transaction fee, payable to a Fund’s custodian,\nmay be imposed for the transfer and other transaction costs associated with the redemption of Creation Units (“Redemption Order\nCosts”). The standard fixed redemption transaction fee for a Fund is $250 for in-kind Creation Units or $100 for cash Creation Units,\nor such other amount as agreed to in writing between the parties, regardless of the number of Creation Units redeemed in the transaction.\nA Fund may adjust the redemption transaction fee from time to time. The fixed redemption fee may be waived on certain orders if a Fund’s\ncustodian has determined to waive some or all of the Redemption Order Costs associated with the order or another party, such as the Adviser,\nhas agreed to pay such fee.

In addition, a variable fee, payable to a Fund, of up to a maximum\nof 2% of the value of the Creation Units subject to the transaction may be imposed for cash redemptions, non-standard orders, or partial\ncash redemptions (when cash redemptions are available) of Creation Units. The variable charge is primarily designed to cover additional\ncosts (e.g., brokerage, taxes) involved with selling portfolio securities to satisfy a cash redemption. A Fund may determine to not charge\na variable fee on certain orders when the Adviser has determined that doing so is in the best interests of Fund shareholders, e.g., for\nredemption orders that facilitate the rebalance of a Fund’s portfolio in a more tax efficient manner than could be achieved without\nsuch order.

Investors who use the services of a broker or other such intermediary\nmay be charged a fee for such services. Investors are responsible for the fixed costs of transferring the Fund Securities from the Trust\nto their account or on their order.

Procedures for Redemption of Creation Units

Orders to redeem Creation Units must be submitted in proper form to\nthe Transfer Agent prior to 4:00 p.m. Eastern Time. A redemption request is considered to be in “proper form” if (i) an\nAuthorized Participant has transferred or caused to be transferred to the Trust’s Transfer Agent the Creation Unit(s) being\nredeemed through the book-entry system of DTC so as to be effective by the time as set forth in the Participant Agreement and (ii) a\nrequest in form satisfactory to the Trust is received by the Transfer Agent from the Authorized Participant on behalf of itself or another\nredeeming investor within the time periods specified in the Participant Agreement. If the Transfer Agent does not receive the investor’s\nFund Shares through DTC’s facilities by the times and pursuant to the other terms and conditions set forth in the Participant Agreement,\nthe redemption request shall be rejected.

The Authorized Participant must transmit the request for redemption,\nin the form required by the Trust, to the Transfer Agent in accordance with procedures set forth in the Authorized Participant Agreement.\nInvestors should be aware that their particular broker may not have executed an Authorized Participant Agreement, and that, therefore,\nrequests to redeem Creation Units may have to be placed by the investor’s broker through an Authorized Participant who has executed\nan Authorized Participant Agreement. Investors making a redemption request should be aware that such request must be in the form specified\nby such Authorized Participant. Investors making a request to redeem Creation Units should allow sufficient time to permit proper submission\nof the request by an Authorized Participant and transfer of the Fund Shares to the Trust’s Transfer Agent; such investors should\nallow for the additional time that may be required to effect redemptions through their banks, brokers or other financial intermediaries\nif such intermediaries are not Authorized Participants.

Additional Redemption Procedures

In connection with taking delivery of Fund Shares of Fund Securities\nupon redemption of Creation Units, a redeeming shareholder or Authorized Participant acting on behalf of such shareholder must maintain\nappropriate custody arrangements with a qualified broker-dealer, bank or other custody providers in each jurisdiction in which any of\na Fund Securities are customarily traded, to which account such Fund Securities will be delivered. Deliveries of redemption proceeds generally\nwill be made within two business days of the trade date.

The Trust may in its discretion exercise its option to redeem such\nFund Shares in cash, and the redeeming investor will be required to receive its redemption proceeds in cash. In addition, an investor\nmay request a redemption in cash that a Fund may, in its sole discretion, permit. In either case, the investor will receive a cash payment\nequal to the NAV of its Fund Shares based on the NAV of Fund Shares next determined after the redemption request is received in proper\nform (minus a redemption transaction fee, if applicable, and additional charge for requested cash redemptions specified above, to offset\nthe Trust’s brokerage and other transaction costs associated with the disposition of Fund Securities). A Fund may also, in its sole\ndiscretion, upon request of a shareholder, provide such redeemer a portfolio of securities that differs from the exact composition of\na Fund Securities but does not differ in NAV.

Redemptions of Fund Shares for Fund Securities will be subject to compliance\nwith applicable federal and state securities laws and a Fund (whether or not it otherwise permits cash redemptions) reserve the right\nto redeem Creation Units for cash to the extent that the Trust could not lawfully deliver specific Fund Securities upon redemptions or\ncould not do so without first registering a Fund Securities under such laws. An Authorized Participant or an investor for which it is\nacting subject to a legal restriction with respect to a particular security included in a Fund Securities applicable to the redemption\nof Creation Units may be paid an equivalent amount of cash. The Authorized Participant may request the redeeming investor of Fund Shares\nto complete an order form or to enter into agreements with respect to such matters as compensating cash payment. Further, an Authorized\nParticipant that is not a “qualified institutional buyer,” (“QIB”) as such term is defined under Rule 144A\nof the Securities Act, will not be able to receive Fund Securities that are restricted securities eligible for resale under Rule 144A.\nAn Authorized Participant may be required by the Trust to provide a written confirmation with respect to QIB status to receive Fund Securities.

The right of redemption may be suspended or the date of payment postponed\nwith respect to a Fund (1) for any period during which the Exchange is closed (other than customary weekend and holiday closings);\n(2) for any period during which trading on the Exchange is suspended or restricted; (3) for any period during which an emergency\nexists as a result of which disposal of Fund Shares or determination of the NAV of Fund Shares is not reasonably practicable; or (4) in\nsuch other circumstance as is permitted by the SEC.

For every occurrence of one or more intervening holidays in the applicable\nforeign market that are not holidays observed in the U.S. equity market, the redemption settlement cycle will be extended by the number\nof such intervening holidays. In addition to holidays, other unforeseeable closings in a foreign market due to emergencies may also prevent\nthe Trust from delivering securities within normal settlement period.

The securities delivery cycles currently practicable for transferring\nportfolio securities to redeeming investors, coupled with foreign market holiday schedules, will require, in certain circumstances, a\ndelivery process longer than seven calendar days for a Fund. Although certain holidays may occur on different dates in subsequent years,\nthe number of days required to deliver redemption proceeds in any given year is not expected to exceed the maximum number of days listed\nbelow for a Fund. The proclamation of new holidays, the treatment by market participants of certain days as “informal holidays”\n(e.g., days on which no or limited securities transactions occur, as a result of substantially shortened trading hours), the elimination\nof existing holidays, or changes in local securities delivery practices, could affect the information set forth herein at some time in\nthe future.

Custom Baskets

Creation and Redemption baskets may differ and a Fund may accept “custom\nbaskets.” A custom basket may include any of the following: (i) a basket that is composed of a non-representative selection\nof a Fund’s portfolio holdings; (ii) a representative basket that is different from the initial basket used in transactions\non the same business day; or (iii) a basket that contains bespoke cash substitutions for a single Authorized Participant. The Fund\nhas adopted policies and procedures that govern the construction and acceptance of baskets, including heightened requirements for certain\ntypes of custom baskets. Such policies and procedures provide the parameters for the construction and acceptance of custom baskets that\nare in the best interests of a Fund and their shareholders, establish processes for revisions to, or deviations from, such parameters,\nand specify the titles and roles of the employees of the Adviser who are required to review each custom basket for compliance with those\nparameters. In addition, when constructing custom baskets for redemptions, the tax efficiency of a Fund may be taken into account. The\npolicies and procedures distinguish among different types of custom baskets that may be used and impose different requirements for different\ntypes of custom baskets in order to seek to mitigate against potential risks of conflicts and/or overreaching by an Authorized Participant.\nThe Adviser has established a governance process to oversee basket compliance for a Fund, as set forth in a Fund’s policies and\nprocedures.

DETERMINATION OF NET ASSET VALUE

The NAV of Fund Shares is determined at the close of regular trading\non the New York Stock Exchange (normally 4:00 p.m. Eastern Time) on each day the NYSE is open. NAV is computed by determining the\naggregate market value of all assets of the applicable Fund, less its liabilities, divided by the total number of Fund Shares outstanding\n((assets-liabilities)/number of Fund Shares = NAV). The NYSE is closed on weekends and New Year’s Day, Martin Luther King, Jr.\nDay, Presidents’ Day, Good Friday, Memorial Day, Juneteenth National Independence Day, Independence Day, Labor Day, Thanksgiving\nDay and Christmas Day. The NAV takes into account the expenses and fees of a Fund, including management, administration, and distribution\nfees, which are accrued daily. The determination of NAV for a Fund for a particular day is applicable to all applications for the purchase\nof Fund Shares, as well as all requests for the redemption of Fund Shares, received by a Fund (or an authorized broker or agent, or its\nauthorized designee) before the close of trading on the NYSE on that day.

Generally, securities traded or dealt in upon one or more securities\nexchanges (whether domestic or foreign) for which market quotations are readily available and not subject to restrictions against resale\nshall be valued at the last quoted sales price on the primary exchange or, in the absence of a sale on the primary exchange, at the mean\nbetween the current bid and ask prices on such exchange. Securities primarily traded in the National Association of Securities Dealers’\nAutomated Quotation System (“NASDAQ”) National Market System for which market quotations are readily available shall be valued\nusing the NASDAQ Official Closing Price. Securities that are not traded or dealt in any securities exchange (whether domestic or foreign)\nand for which over-the-counter market quotations are readily available generally shall be valued at the last sale price or, in the absence\nof a sale, at the mean between the current bid and ask price on such over-the-counter market. Debt securities not traded on an exchange\nmay be valued at prices supplied by a pricing agent(s) based on broker or dealer supplied valuations or matrix pricing, a method\nof valuing securities by reference to the value of other securities with similar characteristics, such as rating, interest rate and maturity.\nFutures, swaps and options contracts listed for trading on a futures or options exchange or board of trade for which market quotations\nare generally available are valued at the last quoted sale price, or, in the absence of a sale, at the mean of the last bid and ask price.\nTotal return swaps on exchange-listed securities are valued at the last quoted sale price, or, in the absence of a sale, at the mean of\nthe last bid and ask price.

If market quotations are not readily available, securities or other\nassets will be valued at their fair market value as determined in good faith by the Adviser in accordance with procedures approved by\nthe Board and evaluated by the Board as to the reliability of the fair value method used. In these cases, a Fund’s NAV will reflect\ncertain portfolio securities’ fair value rather than their market price. Fair value pricing involves subjective judgments, and it\nis possible that the fair value determined for a security or other asset may be materially different than the value that could be realized\nupon the sale of that security or other asset. The fair value prices can differ from market prices when they become available or when\na price becomes available. The Board has delegated execution of these procedures to Calamos Advisors as “valuation designee”\nfor a Fund. Calamos Advisors may also enlist third party consultants such as an audit firm or financial officer of a security issuer on\nan as-needed basis to assist in determining a security-specific fair value. Calamos Advisors reviews and ratifies the execution of this\nprocess and the resultant fair value prices at least quarterly to assure the process produces reliable results.

A Fund may use independent pricing services to assist in calculating\nthe value of a Fund’s securities or other assets. In addition, market prices for foreign securities are not determined at the same\ntime of day as the NAV for a Fund. Because a Fund may invest in securities primarily listed on foreign exchanges, and these exchanges\nmay trade on weekends or other days when a Fund does not price its Fund Shares, the value of some of a Fund’s portfolio securities\nmay change on days when you may not be able to buy or sell Fund Shares.

In computing the NAV, a Fund values foreign securities held by a Fund\nat the latest closing price on the exchange in which they are traded immediately prior to closing of the NYSE. Prices of foreign securities\nquoted in foreign currencies are translated into U.S. dollars at current rates. If events materially affecting the value of a security\nin a Fund’s portfolio, particularly foreign securities, occur after the close of trading on a foreign market but before a Fund prices\nits shares, the security will be valued at fair value. For example, if trading in a portfolio security is halted and does not resume before\na Fund calculates its NAV, the Adviser may need to price the security using a Fund’ fair value pricing guidelines. Without a fair\nvalue price, short-term traders could take advantage of the arbitrage opportunity and dilute the NAV of long-term investors. Fair valuation\nof a Fund’ portfolio securities can serve to reduce arbitrage opportunities available to short-term traders, but there is no assurance\nthat fair value pricing policies will prevent dilution of a Fund’ NAVs by short term traders. The determination of fair value involves\nsubjective judgments. As a result, using fair value to price a security may result in a price materially different from the prices used\nby other funds to determine NAV, or from the price that may be realized upon the actual sale of the security.

With respect to any portion of a Fund’s assets that are invested\nin one or more open-end management investment companies registered under the 1940 Act, a Fund’s NAV is calculated based upon the\nNAVs of those open-end management investment companies, and the prospectuses for these companies explain the circumstances under which\nthose companies will use fair value pricing and the effects of using fair value pricing.

DIVIDENDS AND DISTRIBUTIONS

The following information supplements and should be read in conjunction\nwith the section in the Prospectus entitled “DIVIDENDS, OTHER DISTRIBUTIONS AND TAXES.”

General Policies

The Fund intends to make distributions monthly and distribute long-term\ncapital gains, if any, at least annually.

Dividend Distributions

Dividends and other distributions on Fund Shares are distributed, as\ndescribed below, on a pro rata basis to Beneficial Owners of such Fund Shares. Dividend payments are made through DTC Participants and\nIndirect Participants to Beneficial Owners then of record with proceeds received from the Trust.

Dividend Reinvestment Service

The Trust will not make the DTC book-entry dividend reinvestment service\navailable for use by Beneficial Owners for reinvestment of their cash proceeds, but certain individual broker-dealers may make available\nthe DTC book-entry Dividend Reinvestment Service for use by Beneficial Owners of a Fund through DTC Participants for reinvestment of their\ndividend distributions. Investors should contact their brokers to ascertain the availability and description of these services. Beneficial\nOwners should be aware that each broker may require investors to adhere to specific procedures and timetables in order to participate\nin the dividend reinvestment service and investors should ascertain from their brokers such necessary details. If this service is available\nand used, dividend distributions of both investment income and realized gains will be automatically reinvested in additional whole Fund\nShares issued by the Trust of the same Fund at NAV per Share. Distributions reinvested in additional Shares of a Fund will nevertheless\nbe taxable to Beneficial Owners acquiring such additional Fund Shares to the same extent as if such distributions had been received in\ncash.

TAXATION

This section summarizes some of the main U.S. federal income tax consequences\nof owning shares of the Fund. This section is current as of the date of this SAI. Tax laws and interpretations change frequently, and\nthese summaries do not describe all of the tax consequences to all taxpayers. For example, these summaries generally do not describe your\nsituation if you are a corporation, a non-U.S. person, a broker-dealer, or other investor with special circumstances. In addition, this\nsection does not describe your state, local or foreign tax consequences.

This federal income tax summary is based in part on the advice of counsel\nto a Fund. The Internal Revenue Service could disagree with any conclusions set forth in this section. In addition, our counsel was not\nasked to review, and has not reached a conclusion with respect to the federal income tax treatment of the assets to be deposited in a\nFund. This may not be sufficient for prospective investors to use for the purpose of avoiding penalties under federal tax law.

As with any investment, prospective investors should seek advice based\non their individual circumstances from their own tax advisor.

The Fund intends to qualify annually and to elect to be treated as\na regulated investment company under the Code.

To qualify for the favorable U.S. federal income tax treatment generally\naccorded to regulated investment companies, a Fund must, among other things, (i) derive in each taxable year at least 90% of its\ngross income from dividends, interest, payments with respect to securities loans and gains from the sale or other disposition of stock,\nsecurities or foreign currencies or other income (including but not limited to gains from options, futures, or forward contracts) derived\nwith respect to its business of investing in such stock, securities or currencies, or net income derived from interests in certain publicly\ntraded partnerships; (ii) diversify its holdings so that, at the end of each quarter of the taxable year, (a) at least 50% of\nthe market value of a Fund’s assets is represented by cash and cash items (including receivables), U.S. government securities, the\nsecurities of other regulated investment companies and other securities, with such other securities of any one issuer generally limited\nfor the purposes of this calculation to an amount not greater than 5% of the value of a Fund’s total assets and not greater than\n10% of the outstanding voting securities of such issuer, and (b) not more than 25% of the value of its total assets is invested in\nthe securities (other than U.S. government securities or the securities of other regulated investment companies) of any one issuer, or\ntwo or more issuers which a Fund controls and which are engaged in the same, similar or related trades or businesses, or the securities\nof one or more of certain publicly traded partnerships; and (iii) distribute at least 90% of its investment company taxable income\n(which includes, among other items, dividends, interest and net short-term capital gains in excess of net long-term capital losses) and\nat least 90% of its net tax-exempt interest income each taxable year. There are certain exceptions for failure to qualify if the failure\nis for reasonable cause or is de minimis, and certain corrective action is taken and certain tax payments are made by a Fund.

For purposes of the qualifying income test, the treatment of derivatives\nthat provide exposure to the Autocallable Index is not entirely clear, and thus whether the income and gain therefrom is qualifying income\nis uncertain. An adverse determination or future guidance by the Internal Revenue Service with respect to the treatment of income or gain\nfrom those investments may adversely affect the Fund’s ability to qualify as a regulated investment company. See discussion under\nheading “Tax Risk.”

For purposes of the diversification tests, the identification of the\nissuer (or, in some cases, issuers) of a particular investment can depend on the terms and conditions of such investment. Because there\nis no published Internal Revenue Service guidance or case law on how to determine the “issuer” of various derivatives that\nthe Fund may enter into, there is a risk that the Fund will not meet the Code’s diversification requirements and will not qualify,\nor will be disqualified, as a regulated investment company. See discussion under heading “Tax Risk.”

If determined necessary, the Fund may invest a portion of its assets\nin a Subsidiary, which is expected to provide the Fund with exposure to the Autocallable Index within the limitations of the qualifying\nincome and diversification tests.

As a regulated investment company, the Fund generally will not be subject\nto U.S. federal income tax on its investment company taxable income (as that term is defined in the Code, but without regard to the deduction\nfor dividends paid) and net capital gain (the excess of net long-term capital gain over net short-term capital loss), if any, that it\ndistributes to shareholders. The Fund intends to distribute to its shareholders, at least annually, substantially all of its investment\ncompany taxable income and net capital gain. If a Fund retains any net capital gain or investment company taxable income, it will generally\nbe subject to federal income tax at regular corporate rates on the amount retained. However, if a Fund retains any net capital gain, the\nFund may report the retained amount as undistributed capital gains to shareholders who, if subject to U.S. federal income tax on long-term\ncapital gains, (i) will be required to include in income as long-term capital gain their proportionate share of such undistributed\namount, and (ii) will be entitled to credit their proportionate share of the federal income tax paid by the Fund on the undistributed\namount against their U.S. federal income tax liabilities, if any, and to claim refunds to the extent the credit exceeds such liabilities.\nIf a Fund makes this designation, the tax basis of shares owned by a shareholder of the Fund will, for U.S. federal income tax purposes,\ngenerally be increased by the difference between the amount of undistributed net capital gain included in the shareholder’s gross\nincome and the federal income tax deemed paid by the shareholder.

In addition, amounts not distributed on a timely basis in accordance\nwith a calendar year distribution requirement are subject to a nondeductible 4% excise tax unless, generally, a Fund distributes during\neach calendar year an amount equal to the sum of (1) at least 98% of its ordinary income (not taking into account any capital gains\nor losses) for the calendar year, (2) at least 98.2% of its capital gains in excess of its capital losses (adjusted for certain ordinary\nlosses) for the one-year period ending October 31 of the calendar year, and (3) any ordinary income and capital gains for previous\nyears that were not distributed during those years. In order to prevent application of the excise tax, the Fund intends to make its distributions\nin accordance with the calendar year distribution requirement. A distribution will be treated as paid on December 31 of the current\ncalendar year if it is declared by a Fund in October, November or December with a record date in such a month and paid by a\nFund during January of the following calendar year. Such distributions will be taxable to shareholders in the calendar year in which\nthe distributions are declared, rather than the calendar year in which the distributions are received.

Subject to certain reasonable cause and de minimis exceptions, if a\nFund fails to qualify as a regulated investment company or failed to satisfy the 90% distribution requirement in any taxable year, a Fund\nwould be taxed as an ordinary corporation on its taxable income (even if such income were distributed to its shareholders) and all distributions\nout of earnings and profits would be taxed to shareholders as ordinary income.

Distributions

Dividends paid out of a Fund’s investment company taxable income\nare generally taxable to a shareholder as ordinary income to the extent of a Fund’s earnings and profits, whether paid in cash or\nreinvested in additional shares. However, certain ordinary income distributions paid by a Fund may be taxed at long-term capital gains\ntax rates. In particular, dividends received by an individual shareholder from a regulated investment company such as a Fund may be treated\nas “qualified dividend income” that is eligible to be taxed at the same rates that apply to net capital gain, provided that\ncertain holding period requirements are satisfied by both the Fund and shareholder and provided the dividends are attributable to qualifying\ndividends received by the Fund itself.

A Fund will provide notice to its shareholders of the amount of any\ndistributions that may be taken into account as a dividend, which is eligible for the long-term capital gains tax rates. A Fund cannot\nmake any guarantees as to the amount of any distribution, which will be regarded as a qualified dividend income. It is not anticipated\nthat the Fund will have qualified dividend income.

Income from a Fund may also be subject to a 3.8% “Medicare tax.”\nThis tax generally applies to net investment income if the taxpayer’s adjusted gross income exceeds certain threshold amounts, which\nare $250,000 in the case of married couples filing joint returns and $200,000 in the case of single individuals.

A portion of dividends from the Fund also may be eligible for the dividends-received\ndeduction allowed to corporations, provided certain holding period and other requirements are satisfied. The eligible portion is not permitted\nto exceed the aggregate dividends a Fund receives from U.S. corporations. Funds with higher concentrations of securities other than stock\nof U.S. corporations are generally not expected to designate a significant portion of their distributions as qualifying for the dividends-received\ndeduction.

Distributions of net capital gain (the excess of net long-term capital\ngain over net short-term capital loss), if any, properly reported as capital gain dividends are taxable to a shareholder as long-term\ncapital gains, regardless of how long the shareholder has held Fund Shares. The Internal Revenue Service and the Department of the Treasury\nhave issued regulations that impose special rules in respect of capital gain dividends received through partnership interests constituting\n“applicable partnership interests” under Section 1061 of the Code. Shareholders receiving distributions in the form of\nadditional Fund Shares, rather than cash, generally will have a tax basis in each such Fund Share equal to the value of a share of a Fund\non the reinvestment date. A distribution of an amount in excess of a Fund’s current and accumulated earnings and profits will be\ntreated by a shareholder as a return of capital which is applied against and reduces the shareholder’s basis in his or her Fund\nShares. To the extent that the amount of any such distribution exceeds the shareholder’s basis in his or her Fund Shares, the excess\nwill be treated by the shareholder as gain from a sale or exchange of a Fund Shares.

Shareholders will be notified annually as to the U.S. federal income\ntax status of distributions, and shareholders receiving distributions in the form of additional Fund Shares will receive a report as to\nthe value of those Fund Shares.

Sale or Exchange of Fund Shares

Upon the sale or other disposition of Fund Shares, which a shareholder\nholds as a capital asset, such a shareholder may realize a capital gain or loss, which will be long-term or short-term, depending upon\nthe shareholder’s holding period for the Fund Shares. Generally, a shareholder’s gain or loss will be a long-term gain or\nloss if a Fund Shares have been held for more than one year.

Any loss realized on a sale or exchange will be disallowed to the extent\nthat Fund Shares disposed of are replaced (including through reinvestment of dividends) within a period of 61 days beginning 30 days before\nand ending 30 days after disposition of Fund Shares or to the extent that the shareholder, during such period, acquires or enters into\nan option or contract to acquire, substantially identical stock or securities. In such a case, the basis of the Fund Shares acquired will\nbe adjusted to reflect the disallowed loss. Any loss realized by a shareholder on a disposition of Fund Shares held by the shareholder\nfor six months or less will be treated as a long-term capital loss to the extent of any distributions of long-term capital gain received\nby the shareholder with respect to such Fund Shares.

Taxes on Purchase and Redemption of Creation Units

If a shareholder exchanges securities for Creation Units the shareholder\nwill generally recognize a gain or a loss. The gain or loss will be equal to the difference between the market value of the Creation Units\nat the time plus (or minus) any Cash Component received (or paid) and the shareholder’s aggregate basis in the securities surrendered.\nIf a shareholder exchanges Creation Units for securities, then the shareholder will generally recognize a gain or loss equal to the difference\nbetween the aggregate market value of the securities received, plus (or minus) any Cash Redemption Amount received (or paid), and such\nshareholder’s basis in the Creation Units. The Internal Revenue Service, however, may assert that a loss realized upon an exchange\nof securities for Creation Units or Creation Units for securities cannot be deducted currently under the rules governing “wash\nsales,” or on the basis that there has been no significant change in economic position. In addition, when a regulated investment\ncompany redeems a shareholder in kind, the regulated investment company generally is not required to recognize taxable gains in respect\nof the portfolio securities it distributes to the redeeming shareholder. However, a Fund may be required to recognize taxable gain on\nthe distribution of certain securities, and the Internal Revenue Service may assert that a Fund must recognize taxable gain in respect\nof certain other securities that the Fund distributes to a shareholder in exchange for Creation Units, which may increase the amount of\ntaxable gains that the Fund would otherwise be required to distribute in order to maintain its qualification as a regulated investment\ncompany and avoid a Fund-level tax.

Authorized Participants that are dealers may be subject to special\ntax rules and should consult their own tax advisors regarding the tax consequences of purchasing and redeeming Creation Units in\ntheir capacity as dealers.

Options, Futures and Forward Contracts, and Swap Agreements or Derivatives

In general, option premiums received by a Fund are not immediately\nincluded in the income of the Fund. Instead, the premiums are recognized when the option contract expires, the option is exercised by\nthe holder, or the Fund transfers or otherwise terminates the option (e.g., through a closing transaction). If a call option written by\na Fund is exercised and the Fund sells or delivers the underlying stock, the Fund generally will recognize capital gain or loss equal\nto (a) the sum of the strike price and the option premium received by the Fund minus (b) the Fund’s basis in the stock.\nSuch gain or loss generally will be short-term or long-term depending upon the holding period of the underlying stock. If securities are\npurchased by a Fund pursuant to the exercise of a put option written by it, the Fund generally will subtract the premium received for\npurposes of computing its cost basis in the securities purchased. Gain or loss arising in respect of a termination of a Fund’s obligation\nunder an option other than through the exercise of the option will be short-term gain or loss depending on whether the premium income\nreceived by the Fund is greater or less than the amount paid by the Fund (if any) in terminating the transaction. Thus, for example, if\nan option written by a Fund expires unexercised, the Fund generally will recognize short-term gain equal to the premium received.

The tax treatment of certain positions entered into by a Fund (including\noptions, Box Spreads, box spread ETFs, futures contracts, forward contracts, foreign currency positions and swap agreements) may be governed\nby Section 1256 of the Code (“Section 1256 contracts”). Any gains or losses on Section 1256 contracts are generally\nconsidered 60% long-term and 40% short-term capital gains or losses (“60/40”), although certain foreign currency gains and\nlosses from such contracts may be treated as ordinary in character. Also, Section 1256 contracts held by the Fund at the end of each\ntaxable year (and, for purposes of the 4% excise tax, on certain other dates as prescribed under the Code) are “marked to market”\nwith the result that unrealized gains or losses are treated as though they were realized and the resulting gain or loss is treated as\nordinary or 60/40 gain or loss, as applicable.

The Fund’s options activities may include transactions constituting\nstraddles for U.S. federal income tax purposes, that is, that trigger the straddle rules contained primarily in Section 1092\nof the Code. In some cases, the straddle rules also could apply in connection with swap agreements, Box Spreads, box spread ETFs,\nand the other derivatives. Very generally, where applicable, Section 1092 requires (i) that losses be deferred on positions\ndeemed to be offsetting positions with respect to “substantially similar or related property,” to the extent of unrealized\ngain in the latter, and (ii) that the holding period of such a straddle position that has not already been held for the long-term\nholding period be terminated and begin anew once the position is no longer part of a straddle. Options on single stocks that are not “deep\nin the money” may constitute qualified covered calls, which generally are not subject to the straddle rules; the holding period\non stock underlying qualified covered calls that are “in the money” although not “deep in the money” will be suspended\nduring the period that such calls are outstanding. The straddle rules and the rules governing qualified covered calls may affect\nthe character of gains (or losses) realized by the Fund by causing gains that would otherwise constitute long-term capital gains to be\ntreated as short-term capital gains, and distributions that would otherwise constitute “qualified dividend income” or qualify\nfor the dividends-received deduction to fail to satisfy the holding period requirements and therefore to be taxed as ordinary income or\nto fail to qualify for the dividends-received deduction, as the case may be. In addition, losses realized by the Fund on positions that\nare part of a straddle may be deferred under the straddle rules, rather than being taken into account in calculating the taxable income\nfor the taxable year in which such losses are realized. Because only a few regulations implementing the straddle rules have been\npromulgated, the tax consequences to the Fund of transactions in options Box Spreads, box spread ETFs, futures, forward contracts, and\nswap agreements are not entirely clear.

The Fund may make one or more of the elections available under the\nCode which are applicable to straddles. If the Fund makes any of the elections, the amount, character and timing of gains or losses from\nthe affected straddle positions will be determined under rules that vary according to the election(s) made. The rules applicable\nunder certain of the elections operate to accelerate the recognition of gains or losses from the affected straddle positions. Because\napplication of the straddle rules may affect the character of gains or losses, defer losses and/or accelerate the recognition of\ngains or losses from the affected straddle positions, the amount which must be distributed to shareholders, and which will be taxed to\nshareholders as ordinary income or long-term capital gain, may be increased or decreased substantially as compared to a fund that did\nnot engage in such hedging transactions.

In addition, the Fund’s transactions in other derivative instruments\n(e.g., forward contracts and swap agreements), as well as any of its hedging, short sale, securities loan or similar transactions, may\nbe subject to one or more special tax rules (e.g., notional principal contract, straddle, constructive sale, wash sale and short\nsale rules), which could affect the amount, timing and/or character of distributions to shareholders. The qualifying income and diversification\nrequirements applicable to the Fund’s assets may limit the extent to which the Fund will be able to engage in transactions in options,\nfutures contracts, forward contracts, swap agreements, and other derivative instruments.

Rules governing the tax aspects of swap agreements, Box Spreads,\nbox spread ETFs, and other derivative instruments are in a developing state and not entirely clear in certain respects. Accordingly, while\nthe Fund intends to account for such transactions in a manner it deems to be appropriate, the IRS might not accept such treatment. If\nit did not, the status of a Fund as a regulated investment company might be affected. Calamos Advisors intends to monitor developments\nin this area.

An adverse determination or future guidance by the IRS with respect\nto these rules (which determination or guidance could be retroactive) may affect whether a Fund has made sufficient distributions,\nand otherwise satisfied the relevant requirements, to maintain its qualification as a regulated investment company and avoid a Fund-level\ntax.

Investments in Other Investment Companies

The Fund’s investments in shares of other investment companies\nthat qualify as regulated investment companies (each an “underlying RIC”) can cause the Fund to be required to distribute\ngreater amounts of net investment income or net capital gain than the Fund would have distributed had it invested directly in the securities\nheld by the underlying RIC, rather than in shares of the underlying RIC. Further, the amount or timing of distributions from the Fund\nqualifying for treatment as a particular character (e.g., long-term capital gain, exempt interest, eligibility for dividends-received\ndeduction, etc.) will not necessarily be the same as it would have been had the Fund invested directly in the securities held by\nthe underlying RIC.

If a Fund receives dividends from an underlying RIC and the underlying\nRIC reports such dividends as qualified dividend income, then the Fund is permitted in turn to report a portion of its distributions as\nqualified dividend income, provided the Fund meets holding period and other requirements with respect to shares of the underlying RIC.

If a Fund receives dividends from an underlying RIC and the underlying\nRIC reports such dividends as eligible for the dividends-received deduction, then the Fund is permitted in turn to report its distributions\nderived from those dividends as eligible for the dividends-received deduction as well, provided the Fund meets holding period and other\nrequirements with respect to shares of the underlying RIC.

Nature of Fund Investments

Certain of a Fund’s investment practices are subject to special\nand complex federal income tax provisions that may, among other things, (i) disallow, suspend or otherwise limit the allowance of\ncertain losses or deductions; (ii) convert lower taxed long-term capital gain into higher taxed short-term capital gain or ordinary\nincome; (iii) convert an ordinary loss or a deduction into a capital loss (the deductibility of which is more limited); (iv) cause\na Fund to recognize income or gain without a corresponding receipt of cash; (v) adversely affect the time as to when a purchase or\nsale of stock or securities is deemed to occur; and (vi) adversely alter the characterization of certain complex financial transactions.

Non-U.S. Taxes

Income and proceeds received by a Fund from sources within foreign\ncountries may be subject to withholding and other taxes imposed by such countries, which would reduce the Fund’s return on investments\nin such countries. Tax treaties between certain countries and the U.S. may reduce or eliminate such taxes. Shareholders generally will\nnot be entitled separately to claim a credit or deduction in respect of non-U.S. taxes paid or treated as paid by a Fund. In addition,\na Fund’s investments in foreign securities or foreign currencies may increase or accelerate the Fund’s recognition of ordinary\nincome and may affect the timing or amount of the Fund’s distributions.

Investments in Certain Non-U.S. Corporations

If a Fund holds an equity interest in any “passive foreign investment\ncompanies” (“PFICs”), which are generally certain non-U.S. corporations that receive at least 75% of their annual gross\nincome from passive sources (such as interest, dividends, certain rents and royalties or capital gains) or that hold at least 50% of their\nassets in investments producing such passive income, a Fund could be subject to U.S. federal income tax and additional interest charges\non gains and certain distributions with respect to those equity interests, even if all the income or gain is timely distributed to its\nshareholders. A Fund will not be able to pass through to its shareholders any credit or deduction for such taxes. A Fund may be able to\nmake an election that could ameliorate these adverse tax consequences. For instance, a Fund may elect to mark the gains (and to a limited\nextent losses) in such holdings “to the market” as though it had sold (and, solely for purposes of this mark-to-market election,\nrepurchased) its holdings in those PFICs on the last day of the Fund’s taxable year. If a Fund were to make a mark-to-market election,\nthe Fund would recognize as ordinary income any increase in the value of such PFIC shares, and as ordinary loss any decrease in such value\nto the extent it did not exceed prior increases included in income. Under this election, a Fund might be required to recognize in a year\nincome in excess of its distributions from PFICs and its proceeds from dispositions of PFIC stock during that year, and such income would\nnevertheless be subject to the distribution requirement and would be taken into account for purposes of the 4% excise tax (described above).\nDividends paid by PFICs are not treated as qualified dividend income.

Investments in a Subsidiary

If the Fund invests in a Subsidiary, such Subsidiary is expected to\nbe a controlled foreign corporation (“CFC”) for U.S. federal income tax purposes, in which the Fund will be a U.S. Shareholder.\nIf the Fund is a U.S. Shareholder of a CFC, the Fund will be required to include in gross income for U.S. federal income tax purposes\nall of the CFC’s “subpart F income,” whether or not such income is actually distributed by the CFC. Subpart F income\ngenerally includes net gains from the disposition of stocks or securities, receipts with respect to securities loans, net gains from transactions\n(including futures, forward, and similar transactions) in commodities, and net payments received with respect to equity swaps and similar\nderivatives. Subpart F income is treated as ordinary income, regardless of the character of the CFC’s underlying income. Net losses\nincurred by a CFC during a tax year do not flow through to the Fund and thus will not be available to offset income or capital gain generated\nfrom the Fund’s other investments. In addition, net losses incurred by a CFC during a tax year generally cannot be carried forward\nby the CFC to offset gains realized by it in subsequent taxable years. The Subsidiary may be required to sell investments in order to\nmake cash payments to the Fund, including at a time when it may be disadvantageous to do so.

In addition, if any income earned by a Subsidiary were treated as “effectively\nconnected” with the conduct of a trade or business in the United States (effectively connected income or ECI), such income would\nbe subject to both a so-called “branch profits tax” and a U.S. federal income tax at the rates applicable to U.S. corporations,\nat the entity level. If, for U.S. federal income tax purposes, a Subsidiary were to earn ECI in connection with its direct investment\nactivities, a portion or all of the Subsidiary’s income would be subject to these U.S. taxes. The Fund expects that if it invests\nin a Subsidiary, in general, the activities of the Subsidiary will be conducted in such a manner that it will not be treated as engaged\nin a U.S. trade or business, but there can be no assurance that the entity will not recognize any effectively connected income. The imposition\nof U.S. taxes on ECI could significantly reduce shareholders’ returns on their investments in the Fund.

Under Treasury regulations, subpart F inclusions included in the Fund’s\nannual income for U.S. federal income purposes will constitute qualifying income to the extent it is either (i) timely and currently\nrepatriated or (ii) derived with respect to the Fund’s business of investing in stock, securities or currencies.

Backup Withholding

A Fund may be required to withhold U.S. federal income tax from all\ntaxable distributions and sale proceeds payable to shareholders who fail to provide a Fund with their correct taxpayer identification\nnumber or fail to make required certifications, or who have been notified by the Internal Revenue Service that they are subject to backup\nwithholding. Corporate shareholders and certain other shareholders specified in the Code generally are exempt from such backup withholding.\nThis withholding is not an additional tax. Any amounts withheld may be credited against the shareholder’s U.S. federal income tax\nliability.

Non-U.S. Shareholders

U.S. taxation of a shareholder who, as to the United States, is a nonresident\nalien individual, a non-U.S. trust or estate, a non-U.S. corporation or non-U.S. partnership (“non-U.S. shareholder”) depends\non whether the income of a Fund is “effectively connected” with a U.S. trade or business carried on by the shareholder.

In addition to the rules described in this section concerning\nthe potential imposition of withholding on distributions to non-U.S. persons, distributions to non-U.S. persons that are “financial\ninstitutions” may be subject to a withholding tax of 30% unless an agreement is in place between the financial institution and the\nDepartment of the Treasury to collect and disclose information about accounts, equity investments, or debt interests in the financial\ninstitution held by one or more U.S. persons or the institution is resident in a jurisdiction that has entered into such an agreement\nwith the Department of the Treasury. For these purposes, a “financial institution” means any entity that (i) accepts\ndeposits in the ordinary course of a banking or similar business; (ii) holds financial assets for the account of others as a substantial\nportion of its business; or (iii) is engaged (or holds itself out as being engaged) primarily in the business of investing, reinvesting\nor trading in securities, partnership interests, commodities or any interest (including a futures contract or option) in such securities,\npartnership interests or commodities. The Internal Revenue Service and the Department of the Treasury have issued proposed regulations\nproviding that these withholding rules will not be applicable to the gross proceeds of share redemptions or capital gains dividends\nthat a Fund pays.

Distributions to non-financial non-U.S. entities (other than publicly\ntraded non-U.S. entities, entities owned by residents of U.S. possessions, non-U.S. governments, international organizations, or non-U.S.\ncentral banks), will also be subject to a withholding tax of 30% if the entity does not (i) certify that the entity does not have\nany substantial U.S. owners or (ii) provide the name, address and TIN of each substantial U.S. owner. The Internal Revenue Service\nand the Department of the Treasury have issued proposed regulations providing that these withholding rules will also not be applicable\nto the gross proceeds of share redemptions or capital gains dividends that a Fund pays.

Income Not Effectively Connected

If the income from a Fund is not “effectively connected”\nwith a U.S. trade or business carried on by the non-U.S. shareholder, distributions of investment company taxable income will generally\nbe subject to a U.S. tax of 30% (or lower treaty rate), which tax is generally withheld from such distributions.

Distributions of capital gain dividends and any amounts retained by\na Fund which are properly reported by a Fund as undistributed capital gains will not be subject to U.S. tax at the rate of 30% (or lower\ntreaty rate) unless the non-U.S. shareholder is a nonresident alien individual and is physically present in the United States for more\nthan 182 days during the taxable year and meets certain other requirements. However, this 30% tax on capital gains of nonresident alien\nindividuals who are physically present in the United States for more than the 182 day period only applies in exceptional cases because\nany individual present in the United States for more than 182 days during the taxable year is generally treated as a resident for U.S.\nincome tax purposes; in that case, he or she would be subject to U.S. income tax on his or her worldwide income at the graduated rates\napplicable to U.S. citizens, rather than the 30% U.S. tax. In the case of a non-U.S. shareholder who is a nonresident alien individual,\na Fund may be required to withhold U.S. income tax from distributions of net capital gain unless the non-U.S. shareholder certifies his\nor her non-U.S. status under penalties of perjury or otherwise establishes an exemption. If a non-U.S. shareholder is a nonresident alien\nindividual, any gain such shareholder realizes upon the sale or exchange of such shareholder’s Fund Shares in the United States\nwill ordinarily be exempt from U.S. tax unless the gain is U.S. source income and such shareholder is physically present in the United\nStates for more than 182 days during the taxable year and meets certain other requirements.

Distributions from a Fund that are properly reported by a Fund as an\ninterest-related dividend attributable to certain interest income received by a Fund or as a short-term capital gain dividend attributable\nto certain net short-term capital gain income received by a Fund may not be subject to U.S. federal income taxes, including withholding\ntaxes when received by certain non-U.S. investors, provided that a Fund makes certain elections and certain other conditions are met.

In addition, capital gain distributions attributable to gains from\nU.S. real property interests (including certain U.S. real property holding corporations) will generally be subject to U.S. withholding\ntax and may give rise to an obligation on the part of the non-U.S. shareholder to file a US tax return.

Income Effectively Connected

If the income from a Fund is “effectively connected” with\na U.S. trade or business carried on by a non-U.S. shareholder, then distributions of investment company taxable income and capital gain\ndividends, any amounts retained by a Fund which are properly reported by a Fund as undistributed capital gains and any gains realized\nupon the sale or exchange of Fund Shares will be subject to U.S. income tax at the graduated rates applicable to U.S. citizens, residents\nand domestic corporations. Non-U.S. corporate shareholders may also be subject to the branch profits tax imposed by the Code. The tax\nconsequences to a non-U.S. shareholder entitled to claim the benefits of an applicable tax treaty may differ from those described herein.\nNon-U.S. shareholders are advised to consult their own tax advisors with respect to the particular tax consequences to them of an investment\nin a Fund.

Capital Loss Carryforward

Net capital gains of a Fund that are available for distribution to\nshareholders will be computed by taking into account any applicable capital loss carryforward.

Other Taxation

Fund shareholders may be subject to state, local and foreign taxes\non their Fund distributions. Shareholders are advised to consult their own tax advisors with respect to the particular tax consequences\nto them of an investment in a Fund.

CUSTODIAN AND TRANSFER AGENT

State Street Bank and Trust Company (“State Street”), One\nCongress Street, Boston, Massachusetts 02114-2016, is the custodian for the assets of a Fund. The custodian is responsible for holding\nall cash and securities of a Fund, directly or through a book entry system, delivering and receiving payment for securities sold by a\nFund, receiving and paying for securities purchased by a Fund, collecting income from investments of a Fund and performing other duties,\nall as directed by authorized persons of the Trust. The custodian does not exercise any supervisory functions in such matters as the purchase\nand sale of securities by a Fund, payment of dividends or payment of expenses of a Fund.

State Street also serves as transfer agent and dividend paying agent\nfor a Fund.

FUND ACCOUNTING AND FINANCIAL ACCOUNTING AGENT

The Fund has an agreement with Ernst & Young LLP (“EY”)\nlocated at 155 N. Wacker Drive, Chicago, IL 60606 to provide certain tax services. The tax services include the following: calculating,\ntracking and reporting tax adjustments on all assets of the Fund, including but not limited to contingent debt and preferred trust obligations;\npreparing excise tax and fiscal year distribution schedules; preparing tax information required for financial statement footnotes; preparing\nstate and federal income tax returns; preparing specialized calculations of amortization on convertible securities; preparing year-end\ndividend disclosure information; providing treaty-based foreign withholding tax reclaim services; providing certain global compliance\nand reporting services; providing a match service and analysis of the “passive foreign investment company” status of foreign\ncorporate entities; and providing services related to corporate actions that may or may not have a tax impact on the Fund’s holdings.\nEY receives compensation for these services from the Adviser out of its management fee.

Under the arrangements with State Street to provide fund accounting\nservices, State Street provides certain administrative and accounting services including providing daily reconciliation of cash, trades\nand positions; maintaining general ledger and capital stock accounts; preparing daily trial balance; calculating NAV; providing selected\ngeneral ledger reports; preferred share compliance; calculating total returns; and providing monthly distribution analysis to a Fund.\nA Fund has also entered into an agreement with State Street pursuant to which State Street provides certain administration treasury services\nto a Fund. These services include: monitoring the calculation of expense accrual amounts for a Fund and making any necessary modifications;\nmanaging a Fund’s expenses and expense payment processing; coordinating any expense reimbursement calculations and payment; calculating\nnet investment income dividends and capital gain distributions; coordinating the audits for a Fund; preparing financial reporting statements\nfor a Fund; preparing certain regulatory filings; and calculating asset coverage tests for certain Calamos Funds. State Street receives\ncompensation for these services from the Adviser out of its management fee.

MISCELLANEOUS

Counsel. Ropes & Gray LLP, located at 191 North Wacker\nDrive, 32^nd Floor, Chicago, IL 60606, is counsel to the Trust.

Independent Registered Public Accounting Firm. Deloitte &\nTouche LLP, an independent registered public accounting firm, is the Trust’s independent auditor and is located at 111 South Wacker\nDrive, Chicago, IL 60606. Deloitte & Touche LLP audits and reports on a Fund’s annual financial statements and performs\naudit, audit-related and other services when approved by the Trust’s audit committee.

FINANCIAL STATEMENTS

Because the Fund has not yet commenced operations, financial statements\nare not yet available for the Fund. Deloitte & Touche LLP will audit a Fund’s annual financial statements once the Fund\nbecomes operational. A copy of the Fund’s Annual Report, once available, may be obtained upon request and without charge by writing\nor by calling the Fund at 1-866-363-9219.

EXHIBIT A—DESCRIPTION OF RATINGS⁷

A rating of a rating service represents the service’s opinion\nas to the credit quality of the security being rated. However, the ratings are general and are not absolute standards of quality or guarantees\nas to the creditworthiness of an issuer. Consequently, Calamos Advisors believes that the quality of debt securities in which a Fund invests\nshould be continuously reviewed. A rating is not a recommendation to purchase, sell or hold a security, because it does not take into\naccount market value or suitability for a particular investor. When a security has received a rating from more than one service, each\nrating should be evaluated independently. Ratings are based on current information furnished by the issuer or obtained by the ratings\nservices from other sources that they consider reliable. Ratings may be changed, suspended or withdrawn as a result of changes in or unavailability\nof such information, or for other reasons.

The following is a description of the characteristics of ratings used\nby Moody’s Investors Service (“Moody’s”) and Standard & Poor’s Corporation, a division of The McGraw-Hill\nCompanies (“S&P”).

MOODY’S GLOBAL SHORT-TERM RATING SCALE

P-1: Issuers (or supporting institutions) rated Prime-1 have\na superior ability to repay short-term debt obligations.

P-2: Issuers (or supporting institutions) rated Prime-2 have\na strong ability to repay short-term debt obligations.

P-3: Issuers (or supporting institutions) rated Prime-3 have\nan acceptable ability to repay short-term obligations.

NP: Issuers (or supporting institutions) rated Not Prime do\nnot fall within any of the Prime rating categories.

MOODY’S GLOBAL LONG-TERM RATING SCALE

Aaa—Obligations rated Aaa are judged to be of the highest\nquality, subject to the lowest level of credit risk.

Aa—Obligations rated Aa are judged to be of high quality\nand are subject to very low credit risk.

A—Obligations rated A are judged to be upper-medium grade\nand are subject to low credit risk.

Baa—Obligations rated Baa are judged to be medium-grade\nand subject to moderate credit risk and as such may possess certain speculative characteristics.

Ba—Obligations rated Ba are judged to be speculative and\nare subject to substantial credit risk.

B—Obligations rated B are considered speculative and are\nsubject to high credit risk.

Caa—Obligations rated Caa are judged to be speculative\nof poor standing and are subject to very high credit risk.

Ca—Obligations rated Ca are highly speculative and are\nlikely in, or very near, default, with some prospect of recovery of principal and interest.

C—Obligations rated C are the lowest rated and are typically\nin default, with little prospect for recovery of principal or interest.

⁷ The ratings indicated herein are believed to be the most\nrecent ratings available at the date of this prospectus for the securities listed. Ratings are generally given to securities at the time\nof issuance. While the rating agencies may from time to time revise such ratings, they undertake no obligation to do so, and the ratings\nindicated do not necessarily represent ratings which will be given to these securities on the date of a Fund’s fiscal year-end.

A-1

Note: Moody’s appends numerical modifiers 1, 2, and 3 to each\ngeneric rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic\nrating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic\nrating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers,\nfinance companies, and securities firms.*

*  By their terms, hybrid securities allow for the omission\nof scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid\nsecurities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the\nhybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated\nwith that security.

S&P SHORT-TERM ISSUE CREDIT RATINGS

A-1: A short-term obligation rated ‘A-1’ is rated\nin the highest category by S&P Global Ratings. The obligor’s capacity to meet its financial commitments on the obligation\nis strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity\nto meet its financial commitments on these obligations is extremely strong.

A-2: A short-term obligation rated ‘A-2’ is somewhat\nmore susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories.\nHowever, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.

A-3: A short-term obligation rated ‘A-3’ exhibits\nadequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s\ncapacity to meet its financial commitments on the obligation.

B: A short-term obligation rated ‘B’ is regarded\nas vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments;\nhowever, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.

C: A short-term obligation rated ‘C’ is currently\nvulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial\ncommitments on the obligation.

D: A short-term obligation rated ‘D’ is in default\nor in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an\nobligation are not made on the date due, unless S&P Global Ratings believes that such payments will be made within any stated grace\nperiod. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating\nalso will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual\ncertainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a\ndistressed exchange offer.

S&P LONG-TERM ISSUE CREDIT RATINGS*

Issue credit ratings are based, in varying degrees, on S&P Global\nRatings’ analysis of the following considerations:

●   The likelihood of payment — the capacity\nand willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;

●   The nature and provisions of the financial obligation,\nand the promise we impute; and

●   The protection afforded by, and relative position\nof, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other\nlaws affecting creditors’ rights.

A-2

An issue rating is an assessment of default risk but may incorporate\nan assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior\nobligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and\nsubordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)

AAA—An obligation rated ‘AAA’ has the highest\nrating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.

AA—An obligation rated ‘AA’ differs from the\nhighest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is\nvery strong.

A—An obligation rated ‘A’ is somewhat more\nsusceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However,\nthe obligor’s capacity to meet its financial commitments on the obligation is still strong.

BBB—An obligation rated ‘BBB’ exhibits adequate\nprotection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity\nto meet its financial commitments on the obligation.

BB, B, CCC, CC and C—Obligations rated ‘BB’,\n‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics.\n‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some\nquality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.

BB—An obligation rated ‘BB’ is less vulnerable\nto nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial,\nor economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.

*  Ratings from ‘AA’ to ‘CCC’ may\nbe modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

B—An obligation rated ‘B’ is more vulnerable\nto nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on\nthe obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to\nmeet its financial commitments on the obligation.

CCC—An obligation rated ‘CCC’ is currently\nvulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial\ncommitment on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the\ncapacity to meet its financial commitment on the obligation.

CC—An obligation rated ‘CC’ is currently highly\nvulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a\nvirtual certainty, regardless of the anticipated time to default.

C—An obligation rated ‘C’ is currently highly\nvulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations\nthat are rated higher.

D—An obligation rated ‘D’ is in payment default\nor in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an\nobligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence\nof a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be\nused upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty,\nfor example due to automatic stay provisions. An obligation’s rating is lowered to ‘D’ if it is subject to a distressed\nexchange offer.

A-3

NR—indicates that a rating has not been assigned or is\nno longer assigned.

Local Currency and Foreign Currency Ratings

S&P Global Ratings’ issuer credit ratings make a distinction\nbetween foreign currency ratings and local currency ratings. A foreign currency rating on an issuer will differ from the local currency\nrating on it when the obligor has a different capacity to meet its obligations denominated in its local currency versus obligations denominated\nin a foreign currency.

A-4

CALAMOS ETF TRUST

PART C

OTHER INFORMATION

Item 28. EXHIBITS.

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(a)	(i)	Amended\n and Restated Certificate of Trust of the Registrant (incorporated by reference to Exhibit (a)(ii) to Post-Effective Amendment\n No. 10 to Registrant’s Registration Statement on Form N-1A, filed on January 23, 2023).
	(ii)	Second\n Amended and Restated Trust Instrument (incorporated by reference to Exhibit (a)(iii) to Post-Effective Amendment No. 10\n to Registrant’s Registration Statement on Form N-1A, filed on January 23, 2023).
(b)		Bylaws\n of the Registrant (incorporated by reference to Exhibit (b) to Post-Effective Amendment No. 10 to Registrant’s\n Registration Statement on Form N-1A, filed on January 23, 2023).
(c)		See Articles IV, V, and\n VI of Exhibit (a)(ii) above and Article V of Exhibit (b) above.
(d)	(i)	Investment\n Advisory Agreement dated January 10, 2023 by and between Calamos ETF Trust and Calamos Antetokounmpo Asset Management LLC (incorporated\n by reference to Exhibit (d)(i) to Post-Effective Amendment No. 10 to Registrant’s Registration Statement on\n Form N-1A, filed on January 23, 2023).
	(ii)	Sub-Advisory\n Agreement dated January 10, 2023 by and among Calamos Antetokounmpo Asset Management LLC, Calamos Advisors LLC and Calamos ETF\n Trust (incorporated by reference to Exhibit (d)(ii) to Post-Effective Amendment No. 10 to Registrant’s Registration\n Statement on Form N-1A, filed on January 23, 2023).
	(iii)	Investment\n Advisory Agreement dated September 1, 2023 by and between Calamos ETF Trust and Calamos Advisors LLC (incorporated by reference\n to Exhibit (d)(iii) to Post-Effective Amendment No. 16 to Registrant’s Registration Statement on Form N-1A,\n filed on September 28, 2023).
	(iv)	Amendment,\n dated September 26, 2023, regarding Calamos CEF Income & Arbitrage ETF, to Investment Advisory Agreement by and between\n Calamos ETF Trust and Calamos Advisors LLC (incorporated by reference to Exhibit (d)(iv) to Post-Effective Amendment No. 18\n to Registrant’s Registration Statement on Form N-1A, filed on November 21, 2023).
	(v)	Amendment,\n dated December 12, 2023, regarding Calamos Alternative Nasdaq^® & Bond ETF, to Investment Advisory Agreement\n by and between Calamos ETF Trust and Calamos Advisors LLC (incorporated by reference to Exhibit (d)(v) to Post-Effective\n Amendment No. 22 to Registrant’s Registration Statement on Form N-1A, filed on January 10, 2024).

	(vi)	Amendment,\n dated April 18, 2024, regarding Calamos S&P 500 Structured Alt Protection ETF^® - May, Calamos S&P 500\n Structured Alt Protection ETF^® - August, Calamos S&P 500 Structured Alt Protection ETF^® - July (formerly,\n Calamos S&P 500 Structured Alt Protection ETF^® - November), Calamos S&P 500 Structured Alt Protection ETF^®\n - September (formerly, Calamos S&P 500 Structured Alt Protection ETF^® - February), Calamos Nasdaq-100^®\n Structured Alt Protection ETF^® - June, Calamos Nasdaq-100^® Structured Alt Protection ETF^®\n - September, Calamos Nasdaq-100^® Structured Alt Protection ETF^® - December, and Calamos Nasdaq-100^®\n Structured Alt Protection ETF^® - March, to Investment Advisory Agreement by and between Calamos ETF Trust and Calamos\n Advisors LLC (incorporated by reference to Exhibit (d)(vi) to Post-Effective Amendment No. 30 to Registrant’s\n Registration Statement on Form N-1A, filed on April 22, 2024).
	(vii)	Amendment,\n dated May 22, 2024 regarding Calamos Russell 2000^® Structured Alt Protection ETF^® - July, Calamos\n Russell 2000^® Structured Alt Protection ETF^® - October, Calamos Russell 2000^® Structured\n Alt Protection ETF^® - January, and Calamos Russell 2000^® Structured Alt Protection ETF^®\n - April to Investment Advisory Agreement by and between Calamos ETF Trust and Calamos Advisors LLC (incorporated by reference\n to Exhibit (d)(vii) to Post-Effective Amendment No. 33 to Registrant’s Registration Statement on Form N-1A,\n filed on June 13, 2024).

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	(viii)	Amendment, dated August 12, 2024 regarding Calamos Laddered S&P 500^® Structured Alt Protection ETF^®, Calamos S&P 500^® Structured Alt Protection ETF^® - January, Calamos S&P 500^® Structured Alt Protection ETF^® - February, Calamos S&P 500^® Structured Alt Protection ETF^® - March, Calamos S&P 500^® Structured Alt Protection ETF^® - April, Calamos S&P 500^® Structured Alt Protection ETF^® - June, Calamos S&P 500^® Structured Alt Protection ETF^® - October, Calamos S&P 500^® Structured Alt Protection ETF^® - November, and Calamos S&P 500^® Structured Alt Protection ETF^® - December to Investment Advisory Agreement by and between Calamos ETF Trust and Calamos Advisors LLC (incorporated by reference to Exhibit (d)(viii) to Post-Effective Amendment No. 39 to Registrant’s Registration Statement on Form N-1A, filed on August 23, 2024).
	(ix)	Amendment, dated January 10, 2025 regarding Calamos Bitcoin Structured Alt Protection ETF^® - January, Calamos Bitcoin Structured Alt Protection ETF^® - April, Calamos Bitcoin Structured Alt Protection ETF^® - July and Calamos Bitcoin Structured Alt Protection ETF^® - October to Investment Advisory Agreement by and between Calamos ETF Trust and Calamos Advisors LLC (incorporated by reference to Exhibit (d)(ix) to Post-Effective Amendment No. 52 to Registrant’s Registration Statement on Form N-1A, filed on January 17, 2025).
	(x)	Amendment, dated January 23, 2025 regarding Calamos Bitcoin 90 Series Structured Alt Protection ETF^® - January, Calamos Bitcoin 90 Series Structured Alt Protection ETF^® - April, Calamos Bitcoin 90 Series Structured Alt Protection ETF^® - July, Calamos Bitcoin 90 Series Structured Alt Protection ETF^® - October, Calamos Bitcoin 80 Series Structured Alt Protection ETF^® - January, Calamos Bitcoin 80 Series Structured Alt Protection ETF^® - April, Calamos Bitcoin 80 Series Structured Alt Protection ETF^® - July, Calamos Bitcoin 80 Series Structured Alt Protection ETF^® - October, Calamos Bitcoin Structured Alt Protection ETF^® - 6 Mo Jan/Jul and Calamos Bitcoin Structured Alt Protection ETF^® - 6 Mo Apr/Oct to Investment Advisory Agreement by and between Calamos ETF Trust and Calamos Advisors LLC (incorporated by reference to Exhibit (d)(xi) to Post-Effective Amendment No. 53 to Registrant’s Registration Statement on Form N-1A, filed on January 31, 2025).

	(xi)	Amendment, dated May 2, 2025, regarding name change of Calamos Alternative Nasdaq^® & Bond ETF to Calamos Nasdaq^® Equity & Income ETF to Investment Advisory Agreement by and between Calamos ETF Trust and Calamos Advisors LLC (incorporated by reference to Exhibit (d)(xi) to Post-Effective Amendment No. 57 to Registrant’s Registration Statement on Form N-1A, filed on June 23, 2025).
	(xii)	Amendment, dated June 18, 2025, regarding Calamos Autocallable Income ETF to Investment Advisory Agreement by and between Calamos ETF Trust and Calamos Advisors LLC (incorporated by reference to Exhibit (d)(xii) to Post-Effective Amendment No. 57 to Registrant’s Registration Statement on Form N-1A, filed on June 23, 2025).
	(xiii)	Amendment, dated August 20, 2025 regarding Calamos Laddered Bitcoin Structured Alt Protection ETF^®, Calamos Laddered Bitcoin 90 Series Structured Alt Protection ETF^®, and Calamos Laddered Bitcoin 80 Series Structured Alt Protection ETF^® to Investment Advisory Agreement by and between Calamos ETF Trust and Calamos Advisors LLC (incorporated by reference to Exhibit (d)(xiii) to Post-Effective Amendment No. 63 to Registrant’s Registration Statement on Form N-1A, filed on September 26, 2025).
	(xiv)	Amendment, dated October 9, 2025, regarding Calamos Nasdaq^® Autocallable Income ETF to Investment Advisory Agreement by and between Calamos ETF Trust and Calamos Advisors LLC (incorporated by reference to Exhibit (d)(xiv) to Post-Effective Amendment No. 71 to Registrant’s Registration Statement on Form N-1A, filed on November 5, 2025).
	(xv)	Amendment,\ndated April 8, 2026, regarding Calamos Autocallable Growth ETF and Calamos Tax-Aware Collateral ETF to Investment Advisory Agreement\nby and between Calamos ETF Trust and Calamos Advisors LLC (incorporated by reference to Exhibit (d)(xv) to Post-Effective Amendment\nNo. 82 to Registrant’s Registration Statement on Form N-1A, filed on April 10, 2026).
	(xvi)	Amendment, dated April 8, 2026, regarding Calamos Active Hedged Equity ETF and Calamos Timpani Active SMID Growth ETF to Investment Advisory Agreement by and between Calamos ETF Trust and Calamos Advisors LLC (incorporated by reference to Exhibit (d)(xvi) to Post-Effective Amendment No. 86 to Registrant’s Registration Statement on Form N-1A, filed on June 18, 2026).

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	(xvii)	Amendment, dated September 29, 2026, regarding Calamos Nasdaq^®\nAutocallable Growth ETF and Calamos Least-Of Autocallable Income ETF to Investment Advisory Agreement by and between Calamos ETF Trust\nand Calamos Advisors LLC (incorporated by reference to Exhibit (d)(xvii) to Post-Effective Amendment No. 92 to Registrant’s\nRegistration Statement on Form N-1A, filed on October 14, 2026).
	(xviii)	Investment Advisory Agreement dated June 18, 2025 between Calamos Advisors LLC and Calamos Bitcoin Structured Alt Protection ETF^® - January Sub 1, Calamos Bitcoin Structured Alt Protection ETF^® - April Sub 1, Calamos Bitcoin Structured Alt Protection ETF^® - July Sub 1, Calamos Bitcoin Structured Alt Protection ETF^® - October Sub 1, Calamos Bitcoin Structured Alt Protection ETF^® - 6 Mo Jan/Jul Sub 1, Calamos Bitcoin Structured Alt Protection ETF^® - 6 Mo Apr/Oct Sub 1, Calamos Bitcoin 90 Series Structured Alt Protection ETF^® - January Sub 1, Calamos Bitcoin 90 Series Structured Alt Protection ETF^® - April Sub 1, Calamos Bitcoin 90 Series Structured Alt Protection ETF^® - July Sub 1, Calamos Bitcoin 90 Series Structured Alt Protection ETF^® - October Sub 1, Calamos Bitcoin 80 Series Structured Alt Protection ETF^® - January Sub 1, Calamos Bitcoin 80 Series Structured Alt Protection ETF^® - April Sub 1, Calamos Bitcoin 80 Series Structured Alt Protection ETF^® - July Sub 1, and Calamos Bitcoin 80 Series Structured Alt Protection ETF^® - October Sub 1 (incorporated by reference to Exhibit (d)(xiii) to Post-Effective Amendment No. 57 to Registrant’s Registration Statement on Form N-1A, filed on June 23, 2025).

	(xix)	Amendment, dated September 11, 2025 regarding fund name changes to Investment Advisory Agreement by and between Calamos Advisors LLC and Calamos Bitcoin Structured Alt Protection ETF^® - January Sub 1, Calamos Bitcoin Structured Alt Protection ETF - April^® Sub 1, Calamos Bitcoin Structured Alt Protection ETF^® - July Sub 1, Calamos Bitcoin Structured Alt Protection ETF^® - October Sub 1, Calamos Bitcoin 90 Series Structured Alt Protection ETF^® - January Sub 1, Calamos Bitcoin 90 Series Structured Alt Protection ETF^® - April Sub 1, Calamos Bitcoin 90 Series Structured Alt Protection ETF^® - July Sub 1, Calamos Bitcoin 90 Series Structured Alt Protection ETF^® - October Sub 1, Calamos Bitcoin 80 Series Structured Alt Protection ETF^® - January Sub 1, Calamos Bitcoin 80 Series Structured Alt Protection ETF^® - April Sub 1, Calamos Bitcoin 80 Series Structured Alt Protection ETF^® - July Sub 1, and Calamos Bitcoin 80 Series Structured Alt Protection ETF^® - October Sub 1 (incorporated by reference to Exhibit (d)(xv) to Post-Effective Amendment No. 63 to Registrant’s Registration Statement on Form N-1A, filed on September 26, 2025).
	(xx)	Investment Advisory Agreement dated June 18, 2025 between Calamos Advisors LLC and Calamos Autocallable Income ETF - Sub 1 (incorporated by reference to Exhibit (d)(xiv) to Post-Effective Amendment No. 57 to Registrant’s Registration Statement on Form N-1A, filed on June 23, 2025).
	(xxi)	Investment Advisory Agreement dated October 9, 2025 between Calamos Advisors LLC and Calamos Nasdaq^® Autocallable Income ETF - Sub 1 (incorporated by reference to Exhibit (d)(xviii) to Post-Effective Amendment No. 71 to Registrant’s Registration Statement on Form N-1A, filed on November 5, 2025).
	(xxii)	Investment Advisory Agreement dated April 8, 2026, between Calamos Advisors LLC and Calamos Autocallable Growth ETF - Sub 1 (incorporated by reference to Exhibit (d)(xx) to Post-Effective Amendment No. 82 to Registrant's Registration Statement on Form N-1A, filed on April 10, 2026).
	(xxiii)	Investment Advisory Agreement dated September 29, 2026, between Calamos Advisors LLC and Calamos Nasdaq Autocallable Growth ETF – Sub 1 and Calamos Least-Of Autocallable Income ETF – Sub 1 (incorporated by reference to Exhibit (d)(xxiii) to Post-Effective Amendment No. 92 to Registrant’s Registration Statement on Form N-1A, filed on October 14, 2026).
(e)	(i)	ETF Distribution Agreement dated December 19, 2023 between Calamos ETF Trust and Calamos Financial Services LLC (incorporated by reference to Exhibit (e)(iv) to Post-Effective Amendment No. 22 to Registrant’s Registration Statement on Form N-1A, filed on January 10, 2024).
	(ii)	First Amendment to ETF Distribution Agreement dated April 18, 2024 (incorporated by reference to Exhibit (e)(ii) to Post-Effective Amendment No. 30 to Registrant’s Registration Statement on Form N-1A, filed on April 22, 2024).
	(iii)	Second Amendment to ETF Distribution Agreement dated May 22, 2024 (incorporated by reference to Exhibit (e)(iii) to Post-Effective Amendment No. 33 to Registrant’s Registration Statement on Form N-1A, filed on June 13, 2024).

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	(iv)	Third\n Amendment to ETF Distribution Agreement dated August 12, 2024 (incorporated by reference to Exhibit (e)(iv) to Post-Effective\n Amendment No. 39 to Registrant’s Registration Statement on Form N-1A, filed on August 23, 2024).
	(v)	Fourth\n Amendment to ETF Distribution Agreement dated January 10, 2025 (incorporated by reference to Exhibit (e)(v) to Post\n Effective Amendment No. 52 to Registrant’s Registration Statement on Form N-1A, filed on January 17, 2025).
	(vi)	Fifth\n Amendment to ETF Distribution Agreement dated January 23, 2025 (incorporated by reference to Exhibit (e)(vi) to Post\n Effective Amendment No. 53 to Registrant’s Registration Statement on Form N-1A, filed on January 31, 2025).
	(vii)	Sixth\n Amendment to ETF Distribution Agreement dated June 12, 2025 (incorporated by reference to Exhibit (e)(vii) to Post-Effective\n Amendment No. 57 to Registrant’s Registration Statement on Form N-1A, filed on June 23, 2025).
	(viii)	Seventh\n Amendment to ETF Distribution Agreement dated August 20, 2025 (incorporated by reference to Exhibit (e)(viii) to Post-Effective\n Amendment No. 63 to Registrant’s Registration Statement on Form N-1A, filed on September 26, 2025).
	(ix)	Eighth\n Amendment to ETF Distribution Agreement dated October 9, 2025 (incorporated by reference to Exhibit (e)(ix) to Post-Effective\n Amendment No. 71 to Registrant’s Registration Statement on Form N-1A, filed on November 5, 2025).
	(x)	Ninth Amendment to ETF Distribution Agreement dated April 8, 2026 (incorporated by reference to Exhibit (e)(x) to Post-Effective Amendment No. 82 to Registrant’s Registration Statement on Form N-1A, filed on April 10, 2026).
	(xi)	Tenth Amendment to ETF Distribution Agreement dated May 28, 2026 (incorporated by reference to Exhibit (e)(xi) to Post-Effective Amendment No. 86 to Registrant’s Registration Statement on Form N-1A, filed on June 18, 2026).
	(xii)	Eleventh Amendment\n to ETF Distribution Agreement dated September 29, 2026 (incorporated by reference to Exhibit (e)(xii) to Post-Effective\n Amendment No. 92 to Registrant’s Registration Statement on Form N-1A, filed on October 14, 2026).
(f)		Not applicable.
(g)	(i)	Master\n Custodian Agreement with State Street Bank and Trust Company, dated September 11, 2009 (incorporated by reference to Exhibit (g)(i) to\n Post-Effective Amendment No. 10 to Registrant’s Registration Statement on Form N-1A, filed on January 23, 2023).
	(ii)	Notification\n of Additional Fund, dated December 21, 2022, pursuant to Master Custodian Agreement (incorporated by reference to Exhibit (g)(ii) to\n Post-Effective Amendment No. 10 to Registrant’s Registration Statement on Form N-1A, filed on January 23, 2023).
	(iii)	Notification\n of Additional Funds, dated September 26, 2023, pursuant to Master Custodian Agreement (incorporated by reference to Exhibit (g)(iii) to\n Post-Effective Amendment No. 17 to Registrant’s Registration Statement on Form N-1A, filed on October 6, 2023).
	(iv)	Notification\n of Additional Fund, dated December 12, 2023, pursuant to Master Custodian Agreement (incorporated by reference to Exhibit (g)(iv) to\n Post-Effective Amendment No. 22 to Registrant’s Registration Statement on Form N-1A, filed on January 10, 2024).
	(v)	Notification\n of Additional Funds, dated April 24, 2024, pursuant to Master Custodian Agreement (incorporated by reference to Exhibit (g)(v) to\n Post-Effective Amendment No. 33 to Registrant’s Registration Statement on Form N-1A, filed on June 13, 2024).
	(vi)	Notification\n of Additional Funds, dated May 29, 2024, pursuant to Master Custodian Agreement (incorporated by reference to Exhibit (g)(vi) to\n Post-Effective Amendment No. 33 to Registrant’s Registration Statement on Form N-1A, filed on June 13, 2024).

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

	(vii)	Notification\n of Additional Funds, dated July 1, 2024, pursuant to Master Custodian Agreement (incorporated by reference to Exhibit (g)(vii) to\n Post-Effective Amendment No. 39 to Registrant’s Registration Statement on Form N-1A, filed on August 23, 2024).
	(viii)	Notification\n of Additional Funds, dated August 26, 2024, pursuant to Master Custodian Agreement (incorporated by reference to Exhibit (g)(viii) to\n Post-Effective Amendment No. 40 to Registrant’s Registration Statement on Form N-1A, filed on August 30, 2024).
	(ix)	Notification\n of Additional Funds, dated September 30, 2024, pursuant to Master Custodian Agreement (incorporated by reference to Exhibit (g)(ix) to\n Post-Effective Amendment No. 49 to Registrant’s Registration Statement on Form N-1A, filed on November 21, 2024).
	(x)	Notification\n of Additional Funds, dated November 6, 2024, pursuant to Master Custodian Agreement (incorporated by reference to Exhibit (g)(x) to\n Post-Effective Amendment No. 49 to Registrant’s Registration Statement on Form N-1A, filed on November 21, 2024).
	(xi)	Notification\n of Additional Funds, dated January 24, 2025, pursuant to Master Custodian Agreement (incorporated by reference to Exhibit (g)(xi) to\n Post-Effective Amendment No. 53 to Registrant’s Registration Statement on Form N-1A, filed on January 31, 2025).
	(xii)	Notification\n of Additional Funds, dated June 20, 2025, pursuant to Master Custodian Agreement (incorporated by reference to Exhibit (g)(xii) to\n Post-Effective Amendment No. 57 to Registrant’s Registration Statement on Form N-1A, filed on June 23, 2025).
	(xiii)	Notification\n of Additional Funds, dated September 19, 2025, pursuant to Master Custodian Agreement (incorporated by reference to Exhibit (g)(xiii) to\n Post-Effective Amendment No. 63 to Registrant’s Registration Statement on Form N-1A, filed on September 26,\n 2025).
	(xiv)	Notification\n of Additional Funds, dated October 23, 2025, pursuant to Master Custodian Agreement (incorporated by reference to Exhibit (g)(xiv) to\n Post-Effective Amendment No. 71 to Registrant’s Registration Statement on Form N-1A, filed on November 5, 2025).
	(xv)	Notification\n of Additional Funds, dated May 8, 2026, pursuant to Master Custodian Agreement (incorporated by reference to Exhibit (g)(xv) to\n Post-Effective Amendment No. 86 to Registrant’s Registration Statement on Form N-1A, filed on June 18, 2026).
(h)		Other Material Contracts.
	(i)	Transfer\n Agency and Service Agreement, with State Street Bank and Trust Company dated as of March 21, 2014 (incorporated by reference\n to Exhibit (h)(2) to Pre-Effective Amendment No. 1 to Registrant’s Registration Statement on Form N-1A,\n filed on May 28, 2014).
	(ii)	Notification\n of Additional Fund, dated December 21, 2022, pursuant to Transfer Agency and Service Agreement (incorporated by reference to\n Exhibit (h)(ii) to Post-Effective Amendment No. 10 to Registrant’s Registration Statement on Form N-1A,\n filed on January 23, 2023).
	(iii)	Notification\n of Additional Funds, dated September 26, 2023, pursuant to Transfer Agency and Service Agreement (incorporated by reference\n to Exhibit (h)(iii) to Post-Effective Amendment No. 17 to Registrant’s Registration Statement on Form N-1A,\n filed on October 6, 2023).
	(iv)	Notification\n of Additional Fund, dated December 12, 2023, pursuant to Transfer Agency and Service Agreement (incorporated by reference to\n Exhibit (h)(iv) to Post-Effective Amendment No. 22 to Registrant’s Registration Statement on Form N-1A,\n filed on January 10, 2024).

\n \n \n \n \n \n \n \n \n

	(v)	Notification\n of Additional Funds, dated April 24, 2024, pursuant to Transfer Agency and Service Agreement (incorporated by reference to Exhibit (h)(v) to\n Post-Effective Amendment No. 33 to Registrant’s Registration Statement on Form N-1A, filed on June 13, 2024).
	(vi)	Notification\n of Additional Funds, dated May 29, 2024, pursuant to Transfer Agency and Service Agreement (incorporated by reference to Exhibit (h)(vi) to\n Post-Effective Amendment No. 33 to Registrant’s Registration Statement on Form N-1A, filed on June 13, 2024).

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

	(vii)	Notification\n of Additional Funds, dated July 1, 2024, pursuant to Transfer Agency and Service Agreement (incorporated by reference to Exhibit (h)(vii) to\n Post-Effective Amendment No. 39 to Registrant’s Registration Statement on Form N-1A, filed on August 23, 2024).
	(viii)	Notification\n of Additional Funds, dated August 26, 2024, pursuant to Transfer Agency and Service Agreement (incorporated by reference to\n Exhibit (h)(viii) to Post-Effective Amendment No. 40 to Registrant’s Registration Statement on Form N-1A,\n filed on August 30, 2024).
	(ix)	Notification\n of Additional Funds, dated September 30, 2024, pursuant to Transfer Agency and Service Agreement (incorporated by reference\n to Exhibit (h)(ix) to Post-Effective Amendment No. 49 to Registrant’s Registration Statement on Form N-1A,\n filed on November 21, 2024).
	(x)	Notification\n of Additional Funds, dated November 8, 2024, pursuant to Transfer Agency and Service Agreement (incorporated by reference to\n Exhibit (h)(x) to Post-Effective Amendment No. 49 to Registrant’s Registration Statement on Form N-1A,\n filed on November 21, 2024).
	(xi)	Notification\n of Additional Funds, dated January 24, 2025, pursuant to Transfer Agency and Service Agreement (incorporated by reference to\n Exhibit (h)(xi) to Post-Effective Amendment No. 53 to Registrant’s Registration Statement on Form N-1A,\n filed on January 31, 2025).
	(xii)	Notification\n of Additional Funds, dated June 20, 2025, pursuant to Transfer Agency and Service Agreement (incorporated by reference to Exhibit (h)(xii) to\n Post-Effective Amendment No. 57 to Registrant’s Registration Statement on Form N-1A, filed on June 23, 2025).
	(xiii)	Notification\n of Additional Funds, dated September 19, 2025, pursuant to Transfer Agency and Service Agreement (incorporated by reference\n to Exhibit (h)(xiii) to Post-Effective Amendment No. 63 to Registrant’s Registration Statement on Form N-1A,\n filed on September 26, 2025).
	(xiv)	Notification\n of Additional Funds, dated October 23, 2025, pursuant to Transfer Agency and Service Agreement (incorporated by reference to\n Exhibit (h)(xiv) to Post-Effective Amendment No. 71 to Registrant’s Registration Statement on Form N-1A,\n filed on November 5, 2025).
	(xv)	Notification of Additional Funds, dated May 8, 2026 pursuant to Transfer Agency and Service Agreement (incorporated by reference to Exhibit (h)(xv) to Post-Effective Amendment No. 86 to Registrant’s Registration Statement on Form N-1A, filed on June 18, 2026).
	(xvi)	Administration\n Agreement, effective November 1, 2018, with State Street Bank (incorporated by reference to Exhibit (h)(iii) to Post-Effective\n Amendment No. 10 to Registrant’s Registration Statement on Form N-1A, filed on January 23, 2023).
	(xvii)	Notification\n of Additional Fund, dated December 21, 2022, pursuant to Administration Agreement (incorporated by reference to Exhibit (h)(iv) to\n Post-Effective Amendment No. 10 to Registrant’s Registration Statement on Form N-1A, filed on January 23, 2023).
	(xviii)	Notification\n of Additional Funds, dated October 3, 2023, pursuant to Administration Agreement (incorporated by reference to Exhibit (h)(vi) to\n Post-Effective Amendment No. 17 to Registrant’s Registration Statement on Form N-1A, filed on October 6, 2023).
	(xix)	Amendment\n to Administration Agreement, dated January 4, 2024 (incorporated by reference to Exhibit (h)(viii) to Post-Effective\n Amendment No. 25 to Registrant’s Registration Statement on Form N-1A, filed on February 8, 2024).
	(xx)	Notification\n of Additional Funds, dated April 24, 2024, pursuant to Administration Agreement (incorporated by reference to Exhibit (h)(xii) to\n Post-Effective Amendment No. 33 to Registrant’s Registration Statement on Form N-1A, filed on June 13, 2024).
	(xxi)	Notification\n of Additional Funds, dated May 29, 2024, pursuant to Administration Agreement (incorporated by reference to Exhibit (h)(xiii) to\n Post-Effective Amendment No. 33 to Registrant’s Registration Statement on Form N-1A, filed on June 13, 2024).

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

	(xxii)	Notification\n of Additional Funds, dated July 1, 2024, pursuant to Administration Agreement (incorporated by reference to Exhibit (h)(xv) to\n Post-Effective Amendment No. 39 to Registrant’s Registration Statement on Form N-1A, filed on August 23, 2024).
	(xxiii)	Notification\n of Additional Funds, dated August 26, 2024, pursuant to Administration Agreement (incorporated by reference to Exhibit (h)(xvi) to\n Post-Effective Amendment No. 40 to Registrant’s Registration Statement on Form N-1A, filed on August 30, 2024).
	(xxiv)	Notification\n of Additional Funds, dated September 30, 2024, pursuant to Administration Agreement (incorporated by reference to Exhibit (h)(xix) to\n Post-Effective Amendment No. 49 to Registrant’s Registration Statement on Form N-1A, filed on November 21, 2024).

	(xxv)	Notification\n of Additional Funds, dated November 8, 2024, pursuant to Administration Agreement (incorporated by reference to Exhibit (h)(xx) to\n Post-Effective Amendment No. 49 to Registrant’s Registration Statement on Form N-1A, filed on November 21, 2024).
	(xxvi)	Notification\n of Additional Funds, dated January 24, 2025, pursuant to Administration Agreement (incorporated by reference to Exhibit (h)(xxii) to\n Post-Effective Amendment No. 53 to Registrant’s Registration Statement on Form N-1A, filed on January 31, 2025).
	(xxvii)	Notification\n of Additional Funds, dated June 20, 2025, pursuant to Administration Agreement (incorporated by reference to Exhibit (h)(xxiv) to\n Post-Effective Amendment No. 57 to Registrant’s Registration Statement on Form N-1A, filed on June 23, 2025).
	(xxviii)	Notification\n of Additional Funds, dated September 19, 2025, pursuant to Administration Agreement (incorporated by reference to Exhibit (h)(xxvi) to\n Post-Effective Amendment No. 63 to Registrant’s Registration Statement on Form N-1A, filed on September 26,\n 2025).
	(xxix)	Notification\n of Additional Funds, dated October 23, 2025, pursuant to Administration Agreement (incorporated by reference to Exhibit (h)(xxviii) to\n Post-Effective Amendment No. 71 to Registrant’s Registration Statement on Form N-1A, filed on November 5, 2025).
	(xxx)	Amendment to Administration Agreement, dated May 8, 2026 (incorporated by reference to Exhibit (h)(xxx) to Post-Effective Amendment No. 86 to Registrant’s Registration Statement on Form N-1A, filed on June 18, 2026).
	(xxxi)	Master\n Services Agreement, dated March 15, 2004, with State Street Bank and Trust Company (incorporated by reference to Exhibit (h)(v) to\n Post-Effective Amendment No. 10 to Registrant’s Registration Statement on Form N-1A, filed on January 23, 2023).
	(xxxii)	Notification\n of Additional Funds, dated December 21, 2022, pursuant to the Master Services Agreement (incorporated by reference to Exhibit (h)(vi) to\n Post-Effective Amendment No. 10 to Registrant’s Registration Statement on Form N-1A, filed on January 23, 2023).
	(xxxiii)	Notification\n of Additional Funds, dated September 26, 2023, pursuant to the Master Services Agreement (incorporated by reference to Exhibit (h)(ix) to\n Post-Effective Amendment No. 17 to Registrant’s Registration Statement on Form N-1A, filed on October 6, 2023).
	(xxxiv)	Notification\n of Additional Fund, dated December 12, 2023, pursuant to the Master Services Agreement (incorporated by reference to Exhibit (h)(xii) to\n Post-Effective Amendment No. 22 to Registrant’s Registration Statement on Form N-1A, filed on January 10, 2024).
	(xxxv)	Notification\n of Additional Funds, dated April 24, 2024, pursuant to Master Services Agreement (incorporated by reference to Exhibit (h)(xix) to\n Post-Effective Amendment No. 33 to Registrant’s Registration Statement on Form N-1A, filed on June 13, 2024).
	(xxxvi)	Notification\n of Additional Funds, dated May 29, 2024, pursuant to Master Services Agreement (incorporated by reference to Exhibit (h)(xx) to\n Post-Effective Amendment No. 33 to Registrant’s Registration Statement on Form N-1A, filed on June 13, 2024).

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

	(xxxvii)	Notification\n of Additional Funds, dated July 1, 2024, pursuant to Master Services Agreement (incorporated by reference to Exhibit (h)(xxiii) to\n Post-Effective Amendment No. 39 to Registrant’s Registration Statement on Form N-1A, filed on August 23, 2024).
	(xxxviii)	Notification\n of Additional Funds, dated August 26, 2024, pursuant to Master Services Agreement (incorporated by reference to Exhibit (h)(xxiv) to\n Post-Effective Amendment No. 40 to Registrant’s Registration Statement on Form N-1A, filed on August 30, 2024).
	(xxxix)	Notification\n of Additional Funds, dated September 30, 2024, pursuant to Master Services Agreement (incorporated by reference to Exhibit (h)(xxix) to\n Post-Effective Amendment No. 49 to Registrant’s Registration Statement on Form N-1A, filed on November 21, 2024).
	(xl)	Notification\n of Additional Funds, dated November 8, 2024, pursuant to Master Services Agreement (incorporated by reference to Exhibit (h)(xxx) to\n Post-Effective Amendment No. 49 to Registrant’s Registration Statement on Form N-1A, filed on November 21, 2024).
	(xli)	Notification\n of Additional Funds, dated January 24, 2025, pursuant to Master Services Agreement (incorporated by reference to Exhibit (h)(xxxiii) to\n Post-Effective Amendment No. 53 to Registrant’s Registration Statement on Form N-1A, filed on January 31, 2025).
	(xlii)	Notification\n of Additional Funds, dated June 20, 2025, pursuant to Master Services Agreement (incorporated by reference to Exhibit (h)(xxxvi) to\n Post-Effective Amendment No. 57 to Registrant’s Registration Statement on Form N-1A, filed on June 23, 2025).
	(xliii)	Notification\n of Additional Funds, dated September 19, 2025, pursuant to Master Services Agreement (incorporated by reference to Exhibit (h)(xxxix) to\n Post-Effective Amendment No. 63 to Registrant’s Registration Statement on Form N-1A, filed on September 26,\n 2025).
	(xliv)	Notification\n of Additional Funds, dated October 23, 2025, pursuant to Master Services Agreement (incorporated by reference to Exhibit (h)(xlii) to\n Post-Effective Amendment No. 71 to Registrant’s Registration Statement on Form N-1A, filed on November 5, 2025).
	(xlv)	Notification of Additional Funds, dated May 8, 2026 pursuant to Master Services Agreement (incorporated by reference to Exhibit (h)(xlv) to Post-Effective Amendment No. 86 to Registrant’s Registration Statement on Form N-1A, filed on June 18, 2026).
	(xlvi)	Master\n Services Agreement, effective as of October 16, 2023, with Ernst & Young LLP (incorporated by reference to Exhibit (h)(xvi) to\n Post-Effective Amendment No. 29 to Registrant’s Registration Statement on Form N-1A, filed on April 12, 2024).

	(xlvii)	Form of\n Authorized Participant Agreement (incorporated by reference to Exhibit (h)(vii) to Post-Effective Amendment No. 10\n to Registrant’s Registration Statement on Form N-1A, filed on January 23, 2023).
	(xlviii)	Revised\n Form of Authorized Participant Agreement (incorporated by reference to Exhibit (h)(xiv) to Post-Effective Amendment\n No. 22 to Registrant’s Registration Statement on Form N-1A, filed on January 10, 2024).
	(xlix)	Expense Limitation Agreement for Calamos Autocallable Growth ETF, dated April 8, 2026 (incorporated by reference to Exhibit (h)(xlvi) to Post-Effective Amendment No. 82 to Registrant's Registration Statement on Form N-1A, filed on April 10, 2026).
	(l)	Expense Limitation Agreement, for Calamos Tax-Aware Collateral ETF dated April 8, 2026 (incorporated by reference to Exhibit (h)(xlvii) to Post Effective Amendment No. 83 to Registrant’s Registration Statement on Form N-1A, Filed on April 10, 2026).
	(li)	Expense Limitation Agreement for Calamos Autocallable Income ETF, dated April 15, 2026 (incorporated by reference to Exhibit (h)(xlviii) Post Effective Amendment No. 84 to Registrant’s Registration Statement on Form N-1A, Filed on April 10, 2026).

	(lii)	Expense Limitation Agreement for Calamos Nasdaq^® Autocallable Income ETF, dated April 15, 2026 (incorporated by reference to Exhibit (h)(xlix) Post Effective Amendment No. 85 to Registrant’s Registration Statement on Form N-1A, Filed on November 14, 2025).
	(liii)	Expense Limitation\n Agreement for Calamos Nasdaq^® Autocallable Growth ETF and Calamos Least-Of Autocallable Income ETF, dated September 29, 2026\n (incorporated by reference to Exhibit (h)(liii) to Post-Effective Amendment No. 92 to Registrant’s Registration Statement\n on Form N-1A, filed on October 14, 2026).
(i)		Legal Opinion and Consent\n (filed herewith).
(j)		Not applicable.
(k)		Not applicable.
(l)		Not applicable.
(m)		Rule 12b-1\n Plan (incorporated by reference to Exhibit (m) to Post-Effective Amendment No. 10 to Registrant’s Registration\n Statement on Form N-1A, filed on January 23, 2023).
	(i)	Amendment\n to Rule 12b-1 Plan dated September 26, 2023 (incorporated by reference to Exhibit (m)(i) to Post-Effective Amendment\n No. 16 to Registrant’s Registration Statement on Form N-1A, filed on September 28, 2023).
	(ii)	Amendment\n to Rule 12b-1 Plan dated December 12, 2023 (incorporated by reference to Exhibit (m)(ii) to Post-Effective Amendment\n No. 22 to Registrant’s Registration Statement on Form N-1A, filed on January 10, 2024).
	(iii)	Amendment\n to Rule 12b-1 Plan dated April 18, 2024 (incorporated by reference to Exhibit (m)(iii) to Post-Effective Amendment\n No. 30 to Registrant’s Registration Statement on Form N-1A, filed on April 22, 2024).
	(iv)	Amendment\n to Rule 12b-1 Plan dated May 22, 2024 (incorporated by reference to Exhibit (m)(iv) to Post-Effective Amendment\n No. 33 to Registrant’s Registration Statement on Form N-1A, filed on June 13, 2024).
	(v)	Amendment\n to Rule 12b-1 Plan dated August 12, 2024 (incorporated by reference to Exhibit (m)(v) to Post-Effective Amendment\n No. 39 to Registrant’s Registration Statement on Form N-1A, filed on August 23, 2024).
	(vi)	Amendment\n to Rule 12b-1 Plan dated January 10, 2025 (incorporated by reference to Exhibit (m)(vi) to Post-Effective Amendment\n No. 52 to Registrant’s Registration Statement on Form N-1A, filed on January 17, 2025).
	(vii)	Amendment\n to Rule 12b-1 Plan dated January 23, 2025 (incorporated by reference to Exhibit (m)(vii) to Post-Effective Amendment\n No. 53 to Registrant’s Registration Statement on Form N-1A, filed on January 31, 2025).
	(viii)	Amendment\n to Rule 12b-1 Plan dated June 18, 2025 (incorporated by reference to Exhibit (m)(viii) to Post-Effective Amendment\n No. 57 to Registrant’s Registration Statement on Form N-1A, filed on June 23, 2025).

	(ix)	Amendment\n to Rule 12b-1 Plan dated August 20, 2025 (incorporated by reference to Exhibit (m)(ix) to Post-Effective Amendment\n No. 63 to Registrant’s Registration Statement on Form N-1A, filed on September 26, 2025).
	(x)	Amendment\n to Rule 12b-1 Plan dated October 9, 2025 (incorporated by reference to Exhibit (m)(x) to Post-Effective Amendment\n No. 71 to Registrant’s Registration Statement on Form N-1A, filed on November 5, 2025).
	(xi)	Amendment to Rule 12b-1 Plan dated April 8, 2026 (incorporated by reference to Exhibit (m)(xi) to Post-Effective Amendment No. 82 to Registrant’s Registration Statement on Form N-1A, filed on April 10, 2026).

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

	(xii)	Amendment to Rule 12b-1 Plan dated May 28, 2026 (incorporated by reference to Exhibit (m)(xii) to Post-Effective Amendment No. 86 to Registrant’s Registration Statement on Form N-1A, filed on June 18, 2026).
	(xiii)	Amendment to Rule 12b-1\n Plan dated September 29, 2026 (incorporated by reference to Exhibit (m)(xiii) to Post-Effective Amendment No. 92\n to Registrant’s Registration Statement on Form N-1A, filed on October 14, 2026).
(n)		Not applicable.
(o)		Not applicable.
(p)		Code of Ethics.
	(i)	Code\n of Ethics of Calamos Antetokounmpo Asset Management LLC (“CGAM”), dated April 9, 2026 (incorporated by reference\n to Exhibit (p)(i) to Post-Effective Amendment No. 86 to Registrant’s Registration Statement on Form N-1A,\n filed on June 18, 2026).
	(ii)	Code\n of Ethics and Insider Trading Policy of Registrant, Calamos Advisors LLC, Calamos Financial Services LLC and certain affiliated entities,\n dated April 8, 2026 (incorporated by reference to Exhibit (p)(ii) to Post-Effective Amendment No. 82 to Registrant’s\n Registration Statement on Form N-1A, filed on April 10, 2026).
(q)	(i)	Powers\n of Attorney for Messrs. Neal, Rybak, Wennlund, Toub and Mses. Breen and Stuckey (incorporated by reference to Exhibit (q) to\n Post-Effective Amendment No. 29 to Registrant’s Registration Statement on Form N-1A, filed on April 12, 2024).\n
	(ii)	Powers\n of Attorney for Messrs. Koudounis, Armstrong, and Phlegar (incorporated by reference to Exhibit (q)(ii) to Post-Effective\n Amendment No. 63 to Registrant’s Registration Statement on Form N-1A, filed on September 26, 2025).

Item 29. CONTROL PERSONS.

No person is directly or indirectly controlled by or under common\ncontrol with Calamos Least-Of Autocallable Income ETF.

Item 30. INDEMNIFICATION.

Article IX of the Second Amended and Restated Trust Instrument\nof the Registrant (the “Trust Instrument”) (Exhibit (a)(ii) to this registration statement) provides that, subject\nto certain exceptions and limitations, every person who is, or has been, a trustee or an officer or employee of the Trust or is or was\nserving at the request of the Trust as a trustee, director, officer, employee or agent of another organization in which the Trust has\nany interest as a shareholder, creditor or otherwise (“Covered Person”) shall be indemnified by the Trust and each series\nto the fullest extent permitted by law against liability and against all expenses reasonably incurred or paid by him or her in connection\nwith any claim, action, suit or proceeding in which he or she becomes involved as a party or otherwise by virtue of his or her being\nor having been a Covered Person and against amounts paid or incurred by him or her in the settlement thereof. To the extent required\nunder the Investment Company Act of 1940, as amended, but only to such extent, no indemnification shall be provided hereunder to a Covered\nPerson: (i) who shall have been adjudicated by a court or body before which the proceeding was brought to be liable to the Trust\nor its shareholders by reason of willful misfeasance, bad faith, gross negligence or reckless disregard of the duties involved in the\nconduct of his or her office; or (ii) in the event of a settlement, unless there has been a determination that such Covered Person\ndid not engage in willful misfeasance, bad faith, gross negligence or reckless disregard of the duties involved in the conduct of his\nor her office: (A) by the court or other body approving the settlement; (B) by at least a majority of those trustees who are\nneither interested persons of the Trust nor are parties to the matter based upon a review of readily available facts (as opposed to a\nfull trial-type inquiry); or (C) by written opinion of independent legal counsel based upon a review of readily available facts\n(as opposed to a full trial-type inquiry).

The Trust Instrument also provides that if any shareholder or former\nshareholder of any series is held personally liable solely by reason of his or her being or having been a shareholder and not because\nof his or her acts or omissions or for some other reason, the shareholder or former shareholder (or his or her heirs, executors, administrators\nor other legal representatives or, in the case of any entity, its general successor) shall be entitled out of the assets belonging to\nthe applicable series to be held harmless from and indemnified against all loss and expense arising from such liability. The Trust, on\nbehalf of the affected series, shall, upon request by such shareholder or former shareholder, assume the defense of any claim made against\nhim or

her for any act or obligation of the series and satisfy any judgment\nthereon from the assets belonging to the series. Neither the Trust nor the applicable series shall be responsible for satisfying any\nobligation arising from such a claim that has been settled by the shareholder without the prior written notice to, and consent of, the\nTrust. Except as otherwise specifically provided in this Trust Instrument or in the Bylaws, the Trust shall have no obligation to indemnify\nor hold harmless any shareholder against any loss or expense arising under any circumstances whether in connection with a proceeding\nof any kind or otherwise.

The Registrant, its trustees and officers, its investment adviser,\nthe other investment companies advised by the Advisor and certain persons affiliated with them are insured, within the limits and subject\nto the limitations of the insurance, against certain expenses in connection with the defense of actions, suits or proceedings, and certain\nliabilities that might be imposed as a result of such actions, suits or proceedings. The insurance expressly excludes coverage for any\ntrustee or officer whose personal dishonesty, fraudulent breach of trust, lack of good faith, or intention to deceive or defraud has\nbeen finally adjudicated or may be established or who willfully fails to act prudently.

Insofar as indemnification for liabilities arising under the Securities\nAct of 1933 (the “Securities Act”) may be permitted to trustees, officers, and controlling persons of the Registrant pursuant\nto the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the Securities and Exchange Commission\nsuch indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that\na claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a trustee,\nofficer, or controlling person of the Registrant in the successful defense of any action, suit, or proceeding) is asserted by such trustee,\nofficer, or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its\ncounsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such\nindemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such\nissue.

Item 31. BUSINESS AND OTHER CONNECTIONS OF INVESTMENT ADVISER.

The information in the Statement of Additional Information under the\ncaptions “Management” and “Investment Advisory Services” is incorporated by reference.

Item 32. PRINCIPAL UNDERWRITER.

\n \n \n \n

(a)

Calamos Financial Services LLC (“CFS”)\n serves as principal underwriter for the following investment companies registered under the Investment Company Act of 1940, as amended:\n Calamos Investment Trust, Calamos Advisors Trust, Calamos Antetokounmpo Sustainable Equities Trust, Calamos ETF Trust, Calamos Aksia\n Alternative Credit and Income Fund, Calamos Aksia Private Equity and Alternatives Fund, and Calamos Aksia Hedged Strategies Fund.

\n \n \n \n

(b)

Information on the officers of CFS is set forth below.\n CFS does not have any directors. The principal business address for all named individuals, except Messrs. Kiley and Ojala, is\n 2020 Calamos Court, Naperville, Illinois 60563. The principal business address for Mr. Kiley is 50 Rockefeller Plaza, Suite 1600,\n New York, NY 10020, and the principal business address for Mr. Ojala is 215 North Peoria Street, Chicago, Illinois 60607.

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

Name	Position\n with Underwriter	Position\n with Registrant
John S. Koudounis	President and Chief Executive Officer	Trustee and Vice President
Thomas Kiley	Principal Executive Officer and Chief Distribution\n Officer	Vice President
Daniel Dufresne	Executive Vice President, Chief Operating Officer	Vice President
Christian A. Helmetag	Principal Financial Officer and Principal Operations\n Officer	None
Erik D. Ojala	General Counsel, Secretary and Chief Compliance\n Officer	Vice President and Secretary

\n \n \n \n

(c)	There are no commissions or other compensation received\n from the Registrant directly or indirectly, by any principal underwriter who is not an affiliated person of the Registrant or an\n affiliated person of an affiliated person.

Item 33. LOCATION OF ACCOUNTS AND RECORDS.

All such accounts, books, and other documents are maintained at the\noffices of the Registrant, at the offices of the Registrant’s investment adviser, Calamos Advisors LLC, and CFS, the Registrant’s\nprincipal underwriter, 2020 Calamos Court, Naperville, Illinois 60563, or at the offices of the custodian and transfer agent, State\nStreet Bank & Trust Company, N.A., One Congress Street, Boston, Massachusetts, 02114.

Item 34. MANAGEMENT SERVICES.

None.

Item 35. UNDERTAKINGS.

None.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933 and\nthe Investment Company Act of 1940, as amended, the Registrant certifies that it meets all the requirements for effectiveness of this\nregistration statement under rule 485(b) under the Securities Act and has duly caused this registration statement to be signed\non its behalf by the undersigned, duly authorized, in the City of Naperville, and the State of Illinois on the 14th day of October 2026.

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

Calamos ETF Trust

By:	/s/ John P. Calamos, Sr.
	John P. Calamos, Sr.
	Trustee and President

Pursuant to the requirements of the Securities Act of 1933, this registration\nstatement has been signed below by the following persons in the capacities and on the dates indicated.

\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n

Name	Title	Date

/s/ John\n P. Calamos, Sr.	Trustee and President	October 14, 2026
John P. Calamos, Sr.	(principal executive officer)

/s/ John\n S. Koudounis**	Trustee and Vice President	October 14, 2026
John S. Koudounis

/s/ Hugh\n Armstrong**	Trustee	October 14, 2026
Hugh Armstrong

/s/ Virginia\n G. Breen*	Trustee	October 14, 2026
Virginia G. Breen

/s/ Jeffrey\n S. Phlegar**	Trustee	October 14, 2026
Jeffrey S. Phlegar

/s/ William\n Rybak*	Trustee	October 14, 2026
William Rybak

/s/ Karen\n L. Stuckey*	Trustee	October 14, 2026
Karen L. Stuckey

/s/ Christopher\n M. Toub*	Trustee	October 14, 2026
Christopher M. Toub

/s/ Lloyd\n A. Wennlund*	Trustee	October 14, 2026
Lloyd A. Wennlund

/s/ Thomas\n E. Herman	Vice President and Chief Financial Officer	October 14, 2026
Thomas E. Herman	(principal accounting officer)

\n \n \n \n

An original power of attorney authorizing John P. Calamos, Sr. to execute this Registration Statement, and amendments thereto, for Messrs. Rybak, Toub, Wennlund, and Mses. Breen and Stuckey, each a trustee of the Registrant on whose behalf this Registration Statement is filed, was previously executed, and previously filed as an exhibit.

\n \n \n \n

An original power of attorney authorizing John P. Calamos, Sr. to execute this Registration Statement, and amendments thereto, for Messrs. Koudounis, Armstrong, and Phlegar, each a trustee of the Registrant on whose behalf this Registration Statement is filed, was previously executed, and previously filed as an exhibit.

\n \n \n \n \n

By:

/s/ John P. Calamos, Sr.

\n \n \n \n \n \n \n \n \n \n \n \n \n

	John P. Calamos, Sr.
	Attorney-in-Fact
	October 14, 2026

Exhibit Index

\n \n \n \n \n

(i)

Legal\n Opinion and Consent.

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