0001579881 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:C000276611Member 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member oef:RiskLoseMoneyMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member oef:RiskNotInsuredMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:AmericanDepositaryReceiptsRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:AuthorizedParticipantConcentrationRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:CashHoldingsRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:CostsOfBuyingAndSellingFundSharesMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:CorrelationRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:CoveredCallWritingRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:CurrencyRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:DebtSecuritiesRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:DerivativesRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:EquitySecuritiesRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:FLEXOptionsRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:ForeignSecuritiesRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:ForwardForeignCurrencyContractRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:FuturesAndForwardContractsRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:LiquidityRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:MarketMakerRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:MarketRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:NewFundRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:OptionsRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:OtherInvestmentCompaniesRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:PortfolioSelectionRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:PortfolioTurnoverRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:PremiumDiscountRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:SecondaryMarketTradingRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:SectorRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:TaxRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:TradingIssuesRiskMember 2026-06-18 2026-06-18 0001579881 ck0001579881:S000105820Member ck0001579881:UncoveredCallWritingRiskMember 2026-06-18 2026-06-18 pure iso4217:USD 2026-06-18 N-1A Calamos ETF Trust 2026-06-22 Calamos Active Hedged Equity ETF Investment Objective Calamos Active Hedged Equity ETF (the “Fund”) seeks total return with lower volatility than equity markets. Fees and Expenses of the Fund The following table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund (“Fund Shares”). Investors may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:-1.99pt 0pt 0pt"><td style="min-width:4pt; max-width:4pt"></td><td colspan="3" style="min-width:511.5pt; max-width:511.5pt; vertical-align:bottom">Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):</td></tr> <tr style="display:block; margin:5.25pt 0pt 0pt"><td style="min-width:4pt; max-width:4pt; border-bottom:0.75pt solid #b3b3b3"></td><td style="min-width:467pt; max-width:467pt; padding:1.76pt 0pt 0.93pt; vertical-align:bottom; border-bottom:0.75pt solid #b3b3b3">Management Fees</td><td style="min-width:27.5pt; max-width:27.5pt; padding:1.76pt 0pt 0.93pt; text-align:right; vertical-align:bottom; background-color:#b3b3b3; border-bottom:0.75pt solid #b3b3b3">0.64</td><td style="min-width:17pt; max-width:17pt; padding:1.76pt 0pt 0.93pt; vertical-align:bottom; background-color:#b3b3b3; border-bottom:0.75pt solid #b3b3b3">%</td></tr> <tr style="display:block"><td style="min-width:4pt; max-width:4pt; border-bottom:0.75pt solid #b3b3b3"></td><td style="min-width:467pt; max-width:467pt; padding:1.76pt 0pt 0.93pt; vertical-align:bottom; border-bottom:0.75pt solid #b3b3b3">Distribution and/or Service Fees (12b‑1)</td><td style="min-width:27.5pt; max-width:27.5pt; padding:1.76pt 0pt 0.93pt; text-align:right; vertical-align:bottom; background-color:#e6e6e6; border-bottom:0.75pt solid #b3b3b3">0.00</td><td style="min-width:17pt; max-width:17pt; padding:1.76pt 0pt 0.93pt; vertical-align:bottom; background-color:#e6e6e6; border-bottom:0.75pt solid #b3b3b3">%</td></tr> <tr style="display:block"><td style="min-width:4pt; max-width:4pt; border-bottom:0.75pt solid #b3b3b3"></td><td style="min-width:467pt; max-width:467pt; padding:1.76pt 0pt 0.93pt; vertical-align:bottom; border-bottom:0.75pt solid #b3b3b3">Other Expenses1</td><td style="min-width:27.5pt; max-width:27.5pt; padding:1.76pt 0pt 0.93pt; text-align:right; vertical-align:bottom; background-color:#b3b3b3; border-bottom:0.75pt solid #b3b3b3">0.00</td><td style="min-width:17pt; max-width:17pt; padding:1.76pt 0pt 0.93pt; vertical-align:bottom; background-color:#b3b3b3; border-bottom:0.75pt solid #b3b3b3">%</td></tr> <tr style="display:block"><td style="min-width:4pt; max-width:4pt; border-bottom:0.75pt solid #b3b3b3"></td><td style="min-width:467pt; max-width:467pt; padding:1.76pt 0pt 0.93pt; vertical-align:bottom; border-bottom:0.75pt solid #b3b3b3">Acquired Fund Fees and Expenses2</td><td style="min-width:27.5pt; max-width:27.5pt; padding:1.76pt 0pt 0.93pt; text-align:right; vertical-align:bottom; background-color:#e6e6e6; border-bottom:0.75pt solid #b3b3b3">0.02</td><td style="min-width:17pt; max-width:17pt; padding:1.76pt 0pt 0.93pt; vertical-align:bottom; background-color:#e6e6e6; border-bottom:0.75pt solid #b3b3b3">%</td></tr> <tr style="display:block"><td style="min-width:4pt; max-width:4pt; border-bottom:0.75pt solid #b3b3b3"></td><td style="min-width:467pt; max-width:467pt; padding:1.76pt 0pt 0.93pt; vertical-align:bottom; border-bottom:0.75pt solid #b3b3b3">Total Annual Operating Expenses</td><td style="min-width:27.5pt; max-width:27.5pt; padding:1.76pt 0pt 0.93pt; text-align:right; vertical-align:bottom; background-color:#b3b3b3; border-bottom:0.75pt solid #b3b3b3">0.66</td><td style="min-width:17pt; max-width:17pt; padding:1.76pt 0pt 0.93pt; vertical-align:bottom; background-color:#b3b3b3; border-bottom:0.75pt solid #b3b3b3">%</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:6.82pt 264.5pt 0pt 7.5pt"><td style="min-width:7pt; max-width:7pt; vertical-align:top">1</td><td style="min-width:236.5pt; max-width:236.5pt; vertical-align:bottom">“Other Expenses” are based on estimated amounts for the current fiscal year.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3pt 6.5pt 0pt 7.5pt"><td style="min-width:7pt; max-width:7pt; vertical-align:top">2</td><td style="min-width:494.5pt; max-width:494.5pt; vertical-align:bottom">“Acquired Fund Fees and Expenses” include certain expenses incurred in connection with the Fund’s investment in various closed-end funds, exchange-traded funds (“ETFs”), and business development companies (“BDCs”). The amount shown is based on estimated amounts for the current fiscal year.</td></tr> </table> Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment): 0.0064 0 0 0.0002 0.0066 “Other Expenses” are based on estimated amounts for the current fiscal year. Example This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The example assumes that you invest $10,000 in the Fund for the time periods indicated, and then sell all of your Fund Shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs, whether you sell or hold your Fund Shares, would be: You would pay the following expenses whether you sell or hold your Fund Shares at the end of the period: You would pay the following expenses whether you sell or hold your Fund Shares at the end of the period: <table style="border-collapse:collapse; margin:11.25pt 0pt 0pt; border-top:0.5pt solid #000000; border-bottom:0.5pt solid #000000; border-left:0.5pt solid #000000; border-right:0.5pt solid #000000; border-spacing: 0px;"><tr><td style="min-width:50.15pt; max-width:50.15pt; background-color:#b3b3b3; vertical-align:top; box-sizing:border-box"> </td><td style="min-width:43.8pt; max-width:43.8pt; background-color:#b3b3b3; vertical-align:top; box-sizing:border-box; text-align:center; padding:4.12pt 0pt 1.32pt">One Year </td><td style="min-width:6.8pt; max-width:6.8pt; background-color:#b3b3b3; vertical-align:top; box-sizing:border-box"> </td><td style="min-width:290.8pt; max-width:290.8pt; background-color:#b3b3b3; vertical-align:top; box-sizing:border-box"> </td><td style="min-width:11.4pt; max-width:11.4pt; background-color:#b3b3b3; vertical-align:top; box-sizing:border-box"> </td><td style="min-width:70.2pt; max-width:70.2pt; background-color:#b3b3b3; vertical-align:top; box-sizing:border-box; text-align:center; padding:4.12pt 0pt 1.32pt">Three Years </td><td style="min-width:42.35pt; max-width:42.35pt; background-color:#b3b3b3; vertical-align:top; box-sizing:border-box"> </td></tr> <tr><td style="min-width:50.15pt; max-width:50.15pt; background-color:#e6e6e6; vertical-align:top; border-bottom:0.5pt solid #b3b3b3; box-sizing:border-box"> </td><td style="min-width:43.8pt; max-width:43.8pt; background-color:#e6e6e6; vertical-align:top; border-bottom:0.5pt solid #b3b3b3; box-sizing:border-box; text-align:center; padding:2.51pt 0pt 1.61pt">$67 </td><td style="min-width:6.8pt; max-width:6.8pt; background-color:#e6e6e6; vertical-align:top; border-bottom:0.5pt solid #b3b3b3; box-sizing:border-box"> </td><td style="min-width:290.8pt; max-width:290.8pt; background-color:#e6e6e6; vertical-align:top; border-bottom:0.5pt solid #b3b3b3; box-sizing:border-box"> </td><td style="min-width:11.4pt; max-width:11.4pt; background-color:#e6e6e6; vertical-align:top; border-bottom:0.5pt solid #b3b3b3; box-sizing:border-box"> </td><td style="min-width:70.2pt; max-width:70.2pt; background-color:#e6e6e6; vertical-align:top; border-bottom:0.5pt solid #b3b3b3; box-sizing:border-box; text-align:center; padding:2.51pt 0pt 1.61pt">$211 </td><td style="min-width:42.35pt; max-width:42.35pt; background-color:#e6e6e6; vertical-align:top; border-bottom:0.5pt solid #b3b3b3; box-sizing:border-box"> </td></tr> <tr><td style="min-width:50.15pt; max-width:50.15pt; vertical-align:top; border-top:0.5pt solid #000000; box-sizing:border-box"> </td><td style="min-width:43.8pt; max-width:43.8pt; vertical-align:top; border-top:0.5pt solid #000000; box-sizing:border-box"> </td><td style="min-width:6.8pt; max-width:6.8pt; vertical-align:top; border-top:0.5pt solid #000000; box-sizing:border-box"> </td><td style="min-width:290.8pt; max-width:290.8pt; vertical-align:top; border-top:0.5pt solid #000000; box-sizing:border-box"> </td><td style="min-width:11.4pt; max-width:11.4pt; vertical-align:top; border-top:0.5pt solid #000000; box-sizing:border-box"> </td><td style="min-width:70.2pt; max-width:70.2pt; vertical-align:top; border-top:0.5pt solid #000000; box-sizing:border-box"> </td><td style="min-width:42.35pt; max-width:42.35pt; vertical-align:top; border-top:0.5pt solid #000000; box-sizing:border-box"> </td></tr> </table> <table style="border-collapse:collapse; margin:11.25pt 0pt 0pt; border-top:0.5pt solid #000000; border-bottom:0.5pt solid #000000; border-left:0.5pt solid #000000; border-right:0.5pt solid #000000; border-spacing: 0px;"><tr><td style="min-width:50.15pt; max-width:50.15pt; background-color:#b3b3b3; vertical-align:top; box-sizing:border-box"> </td><td style="min-width:43.8pt; max-width:43.8pt; background-color:#b3b3b3; vertical-align:top; box-sizing:border-box; text-align:center; padding:4.12pt 0pt 1.32pt">One Year </td><td style="min-width:6.8pt; max-width:6.8pt; background-color:#b3b3b3; vertical-align:top; box-sizing:border-box"> </td><td style="min-width:290.8pt; max-width:290.8pt; background-color:#b3b3b3; vertical-align:top; box-sizing:border-box"> </td><td style="min-width:11.4pt; max-width:11.4pt; background-color:#b3b3b3; vertical-align:top; box-sizing:border-box"> </td><td style="min-width:70.2pt; max-width:70.2pt; background-color:#b3b3b3; vertical-align:top; box-sizing:border-box; text-align:center; padding:4.12pt 0pt 1.32pt">Three Years </td><td style="min-width:42.35pt; max-width:42.35pt; background-color:#b3b3b3; vertical-align:top; box-sizing:border-box"> </td></tr> <tr><td style="min-width:50.15pt; max-width:50.15pt; background-color:#e6e6e6; vertical-align:top; border-bottom:0.5pt solid #b3b3b3; box-sizing:border-box"> </td><td style="min-width:43.8pt; max-width:43.8pt; background-color:#e6e6e6; vertical-align:top; border-bottom:0.5pt solid #b3b3b3; box-sizing:border-box; text-align:center; padding:2.51pt 0pt 1.61pt">$67 </td><td style="min-width:6.8pt; max-width:6.8pt; background-color:#e6e6e6; vertical-align:top; border-bottom:0.5pt solid #b3b3b3; box-sizing:border-box"> </td><td style="min-width:290.8pt; max-width:290.8pt; background-color:#e6e6e6; vertical-align:top; border-bottom:0.5pt solid #b3b3b3; box-sizing:border-box"> </td><td style="min-width:11.4pt; max-width:11.4pt; background-color:#e6e6e6; vertical-align:top; border-bottom:0.5pt solid #b3b3b3; box-sizing:border-box"> </td><td style="min-width:70.2pt; max-width:70.2pt; background-color:#e6e6e6; vertical-align:top; border-bottom:0.5pt solid #b3b3b3; box-sizing:border-box; text-align:center; padding:2.51pt 0pt 1.61pt">$211 </td><td style="min-width:42.35pt; max-width:42.35pt; background-color:#e6e6e6; vertical-align:top; border-bottom:0.5pt solid #b3b3b3; box-sizing:border-box"> </td></tr> <tr><td style="min-width:50.15pt; max-width:50.15pt; vertical-align:top; border-top:0.5pt solid #000000; box-sizing:border-box"> </td><td style="min-width:43.8pt; max-width:43.8pt; vertical-align:top; border-top:0.5pt solid #000000; box-sizing:border-box"> </td><td style="min-width:6.8pt; max-width:6.8pt; vertical-align:top; border-top:0.5pt solid #000000; box-sizing:border-box"> </td><td style="min-width:290.8pt; max-width:290.8pt; vertical-align:top; border-top:0.5pt solid #000000; box-sizing:border-box"> </td><td style="min-width:11.4pt; max-width:11.4pt; vertical-align:top; border-top:0.5pt solid #000000; box-sizing:border-box"> </td><td style="min-width:70.2pt; max-width:70.2pt; vertical-align:top; border-top:0.5pt solid #000000; box-sizing:border-box"> </td><td style="min-width:42.35pt; max-width:42.35pt; vertical-align:top; border-top:0.5pt solid #000000; box-sizing:border-box"> </td></tr> </table> 67 67 211 211 Portfolio Turnover The Fund pays 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 Annual Fund Operating Expenses or in the example, affect the Fund’s performance. Because the Fund has not yet commenced operations, portfolio turnover information is unavailable at this time. Principal Investment Strategies The Fund seeks to achieve total return with lower volatility than equity markets. Under normal circumstances, the Fund invests at least 80% of its net assets (plus any borrowings for investment purposes) in shares of other registered investment companies which in turn seek to provide investment results that, before expenses, correspond generally to the price and yield performance of the S&P 500® Index (the “S&P 500”), including, but not limited to, the State Street® SPDR® Portfolio S&P 500® ETF (“SPYM”), the State Street SPDR® S&P 500 ETF Trust (“SPY”) or the Vanguard S&P 500 ETF (“VOO”) (collectively, the ”S&P 500® Funds”). The Fund invests in the S&P 500® Funds while also buying and selling index call and put options and/or entering into other options strategies, including the use of Flexible Exchange Options (“FLEX Options”) on the S&P 500® Funds and/or broad based indices (such as the S&P 500 or MSCI EAFE Index) or ETFs (exchange-traded funds). In addition, to seek to offset some of the risk of a potential decline in value of certain long positions, the Fund may also purchase put options on the S&P 500® Funds or broad-based securities indices (such as the S&P 500). The Fund may also engage in active and frequent trading of portfolio securities.Equity securities purchased by the Fund may also include U.S. exchange-listed common stocks, options on equities, and American Depositary Receipts (ADRs). The Fund may also invest in fixed-income securities. The Fund may also invest in ETFs. The Fund may use derivatives for hedging (attempting to reduce risk by offsetting one investment position with another) or non-hedging purposes. In particular, the Fund may hedge some or all of the currency exposure of foreign securities by entering into forward foreign currency contracts, futures or other derivatives. The Fund intends that its option-based risk management strategy will reduce the volatility inherent in investments in equity securities over time. 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 State Street 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. An investment in the Fund is subject to risks, and you could lose money on your investment in the Fund. Your investment in the Fund is not a deposit in a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:5.5pt 1pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:492pt; max-width:492pt; vertical-align:bottom">American Depositary Receipts Risk — The stocks of most foreign companies that trade in the U.S. markets are traded as ADRs. U.S. depositary banks issue these stocks. Each ADR represents one or more shares of foreign stock or a fraction of a share. The price of an ADR corresponds to the price of the foreign stock in its home market, adjusted to the ratio of the ADRs to foreign company shares. Therefore while purchasing a security on a U.S. exchange, the risks inherently associated with foreign investing still apply to ADRs.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 4pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:489pt; max-width:489pt; vertical-align:bottom">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.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:-2.79pt 0pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:493pt; max-width:493pt; vertical-align:bottom">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.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 3pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:490pt; max-width:490pt; vertical-align:bottom">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.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 0pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:493pt; max-width:493pt; vertical-align:bottom">Correlation Risk — The effectiveness of the Fund’s index option-based risk management strategy may be reduced if the performance of the Fund’s equity portfolio does not correlate to that of the indices underlying its option positions.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 0pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:493pt; max-width:493pt; vertical-align:bottom">Covered Call Writing Risk — As the writer of a covered call option on a security, the Fund foregoes, during the option’s life, the opportunity to profit from increases in the market value of the security covering the call option above the sum of the premium and the exercise price of the call.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 8pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:485pt; max-width:485pt; vertical-align:bottom">Currency Risk — To the extent that the Fund invests in securities or other instruments denominated in or indexed to foreign currencies, changes in currency exchange rates bring an added dimension of risk. Currency fluctuations could negatively impact investment gains or add to investment losses. Although the Fund may attempt to hedge against currency risk, the hedging instruments may not always perform as the Fund expects and could produce losses. Suitable hedging instruments may not be available for currencies of emerging market countries. The Fund’s investment adviser may determine not to hedge currency risks, even if suitable instruments appear to be available.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 0pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:493pt; max-width:493pt; vertical-align:bottom">Debt Securities Risk — Debt securities are subject to various risks, including interest rate risk, credit risk and default risk.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 0pt 0pt 23pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:484pt; max-width:484pt; vertical-align:bottom">Interest Rate Risk — The value of debt securities generally decreases in periods when interest rates are rising. In addition, interest rate changes typically have a greater effect on prices of longer-term debt securities than shorter term debt securities. Changes in interest rates by the Federal Reserve Board, and other events affecting fixed-income markets, may subject the Fund to heightened interest rate risk as a result of a rise in interest rates.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 0pt 0pt 23pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:484pt; max-width:484pt; vertical-align:bottom">Credit Risk — A debt security could deteriorate in quality to such an extent that its rating is downgraded or its market value declines relative to comparable securities. Changes in actual or perceived creditworthiness may occur quickly. If the Fund holds securities that have been downgraded, or that default on payment, the Fund’s performance could be negatively affected.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 7pt 0pt 23pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:477pt; max-width:477pt; vertical-align:bottom">Default Risk — A company that issues a debt security may be unable to fulfill its obligation to repay principal and interest. The lower a bond is rated, the greater its default risk. To the extent the Fund holds securities that have been downgraded, or that default on payment, its performance could be negatively affected.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 5pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:488pt; max-width:488pt; vertical-align:bottom">Derivatives Risk — Derivatives are instruments, such as futures and forward foreign currency contracts, whose value is derived from that of other assets, rates or indices. The use of derivatives for non-hedging purposes may be considered more speculative than other types of investments. Derivatives can be used for hedging (attempting to reduce risk by offsetting one investment position with another) or non-hedging purposes. Hedging with derivatives may increase expenses, and there is no guarantee that a hedging strategy will work. While hedging 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.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 0pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:493pt; max-width:493pt; vertical-align:bottom">Equity Securities Risk — The securities markets are volatile, and the market prices of the Fund’s securities may decline generally. The price of equity securities fluctuates based on changes in a company’s financial condition and overall market and economic conditions. If the market prices of the securities owned by the Fund (i.e., the Fund’s long position) fall, the value of your investment in the Fund will decline.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:-2.79pt 0pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:493pt; max-width:493pt; vertical-align:bottom">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.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 0pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:493pt; max-width:493pt; vertical-align:bottom">Foreign Securities Risk — Risks associated with investing in foreign securities include fluctuations in the exchange rates of foreign currencies that may affect the U.S. dollar value of a security, the possibility of substantial price volatility as a result of political and economic instability in the foreign country, less public information about issuers of securities, different securities regulation, different accounting, auditing and financial reporting standards, and less liquidity than in U.S. markets.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 0pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:493pt; max-width:493pt; vertical-align:bottom">Forward Foreign Currency Contract Risk — Forward foreign currency contracts are contractual agreements to purchase or sell a specified currency at a specified future date (or within a specified time period) at a price set at the time of the contract. The Fund may not fully benefit from, or may lose money on, forward foreign currency transactions if changes in currency exchange rates do not occur as anticipated or do not correspond accurately to changes in the value of the Fund’s holdings.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 0pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:493pt; max-width:493pt; vertical-align:bottom">Futures and Forward Contracts Risk — Futures contracts provide for the future sale by one party and purchase by another of a specific asset at a specific time and price (with or without delivery required). Futures contracts are standardized contracts traded on a recognized exchange. An option on a futures contract gives the purchaser the right, in exchange for a premium, to assume a position in a futures contract at a specified exercise price during the term of the option. Futures and forward contracts are subject to counterparty risk, meaning that the party with whom the Fund enters into the derivatives transaction (the clearinghouse or the broker holding the Fund’s position for a futures contract or the counterparty for a forward contract) may experience a significant credit event and/or may be unwilling or unable to make timely settlement payments or otherwise honor its obligations.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:-2.79pt 0pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:493pt; max-width:493pt; vertical-align:bottom">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.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 0pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:493pt; max-width:493pt; vertical-align:bottom">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 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.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 0pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:493pt; max-width:493pt; vertical-align:bottom">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 S&P 500® Funds.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 12pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:481pt; max-width:481pt; vertical-align:bottom">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.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 0pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:493pt; max-width:493pt; vertical-align:bottom">Options Risk — The Fund’s ability to close out its position as a purchaser or seller of an over-the-counter or exchange-listed put or call option is dependent, in part, upon the liquidity of the options market. There are significant differences between the securities and options markets that could result in an imperfect correlation among these markets, causing a given transaction not to achieve its objectives. The Fund’s ability to utilize options successfully will depend on the ability of the Fund’s investment adviser to predict pertinent market movements, which cannot be assured. The Fund may also purchase or write over-the-counter put or call options, which involves risks different from, and possibly greater than, the risks associated with exchange-listed put or call options. In some instances, over-the-counter put or call options may expose the Fund to the risk that a counterparty may be unable or unwilling to perform according to a contract, and that any deterioration in a counterparty’s creditworthiness could adversely affect the instrument. In addition, the Fund may be exposed to a risk that losses may exceed the amount originally invested. </td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 0pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:493pt; max-width:493pt; vertical-align:bottom">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 BDCs 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. Accordingly, if the Fund serves as an “underlying fund” to another investment company, the Fund’s ability to invest in other investment companies, private funds and other investment vehicles may be limited and, under these circumstances, the Fund’s investments in other investment companies, private funds and other investment vehicles will be consistent with applicable law and/or exemptive relief obtained from the SEC. 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.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:-2.79pt 6pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:487pt; max-width:487pt; vertical-align:bottom">Portfolio Selection Risk — The value of your investment may decrease if the investment adviser’s judgment about the attractiveness, value or market trends affecting a particular security, issuer, industry, or sector or about market movements is incorrect.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 0pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:493pt; max-width:493pt; vertical-align:bottom">Portfolio Turnover Risk — The portfolio managers may actively and frequently trade securities or other instruments in the Fund’s portfolio to carry out its investment strategies. A high portfolio turnover rate increases transaction costs, which may increase the Fund’s expenses. Frequent and active trading may also cause adverse tax consequences for investors in the Fund due to an increase in short-term capital gains.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 1pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:492pt; max-width:492pt; vertical-align:bottom">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.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 0pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:493pt; max-width:493pt; vertical-align:bottom">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.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 0pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:493pt; max-width:493pt; vertical-align:bottom">Sector Risk — To the extent the Fund invests a significant portion of its assets in a particular sector, a greater portion of the Fund’s performance may be affected by the general business and economic conditions affecting that sector. Each sector may share economic risk with the broader market, however there may be economic risks specific to each sector. As a result, returns from those sectors may trail returns from the overall stock market and it is possible that the Fund may underperform the broader market, or experience greater volatility.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 1pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:492pt; max-width:492pt; vertical-align:bottom">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 Internal Revenue Code of 1986, as amended (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. 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.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 6pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:487pt; max-width:487pt; vertical-align:bottom">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.</td></tr> </table> <table cellpadding="0" style="border-collapse:collapse; border-spacing: 0px;"> <tr style="display:block; margin:3.5pt 0pt 0pt 14pt"><td style="min-width:9pt; max-width:9pt; vertical-align:top">•</td><td style="min-width:493pt; max-width:493pt; vertical-align:bottom">Uncovered Call Writing Risk — If the Fund writes an uncovered call option, there is no underlying security held by the Fund that can act as a partial hedge. As the writer of an uncovered call option on a security, the Fund is exposed to the risk of loss if the market price of the underlying security increases and the risk that the Fund may not be able to enter into a closing transaction because of an illiquid secondary market.</td></tr> </table> 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. The Fund has not commenced operations as of the date of this prospectus. www.calamos.com Past performance (before and after taxes) is not an indication of future performance. 485BPOS 0001579881 false “Acquired Fund Fees and Expenses” include certain expenses incurred in connection with the Fund’s investment in various closed-end funds, exchange-traded funds (“ETFs”), and business development companies (“BDCs”). The amount shown is based on estimated amounts for the current fiscal year. “Other Expenses” are based on estimated amounts for the current fiscal year.