Summary Prospectus by Investment Company (Form 497K)

Before you invest, you may want to review the Fund's Prospectus, which contains more information about the Fund and its risks. You can find the Fund's Prospectus and other information about the Fund online at im.natixis.com/funddocuments. You can also get this information at no cost by calling 800-862-4863 or by sending an e-mail request to [email protected]. The Fund's Prospectus and Statement of Additional Information, each dated May 1, 2026, as may be revised or supplemented from time to time, are incorporated by reference into this Summary Prospectus.

Investment Goal

The Fund seeks to deliver current income while maintaining prospects for capital appreciation.

Fund Fees & Expenses

The following table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in this table. If such expenses were reflected, the expenses set forth below would be higher.

Annual Fund Operating Expenses

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 (whether or not shares are redeemed), and also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same, except that the example is based on the Total Annual Fund Operating Expenses After Fee Waiver and/or Expense Reimbursement assuming that such waiver and/or reimbursement will only be in place through the date noted above and on the Total Annual Fund Operating Expenses for the remaining periods. The example does not take into account brokerage commissions and other fees to financial intermediaries that you may pay on your purchases and sales of shares of the Fund. It also does not include the transaction fees on purchases and redemptions of creation units ("Creation Units"), because those fees will not be imposed on retail investors. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:

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 for you if your 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. During its most recently ended fiscal year, the Fund's portfolio turnover rate was 65% of the average value of its portfolio.

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Fund Summary

Investments, Risks and Performance

Principal Investment Strategies

The Fund is an actively-managed exchange-traded fund ("ETF") that seeks to achieve its investment objective by investing in high-quality stocks and written index call option exposure. The Fund may use listed index options or equity-linked notes to achieve the written index call option exposure.

Equity Portfolio

Under normal circumstances, the Fund invests in a diversified portfolio of U.S. large- and mid-capitalization stocks with quality characteristics identified through certain fundamental metrics determined by Gateway Investment Advisers, LLC (the "Subadviser"). Generally, the Subadviser believes that a high-quality company is a company that has an established business with high relative profitability characteristics and low leverage. For these purposes, large-capitalization companies are those that, at the time of purchase, generally have market capitalizations of at least $10 billion and mid-capitalization companies are those that, at the time of purchase, generally have market capitalizations of between $2 billion and $10 billion.

The Subadviser uses a multifactor quantitative model to construct and manage the stock portfolio. The model evaluates U.S.-exchange-traded equities that meet criteria and constraints established by the Subadviser. A quality score is assigned to each security in the investment universe based on systematic factors including profitability and leverage. The strategy seeks to maximize exposure to the weighted quality score, while considering active exposures to individual names, sectors, and the market as a whole. The equity portfolio generally consists of approximately 75-150 securities. Equity securities purchased by the Fund may include U.S. exchange-listed common stocks, preferred stocks, American Depository Receipts and investment companies (including ETFs). The Fund may invest in affiliated and unaffiliated mutual funds and ETFs, to the extent permitted by the Investment Company Act of 1940, as amended (the "1940 Act"). The holdings may be rebalanced as frequently as desired by the Subadviser to maintain the overall desired exposure to the quality factor.

Equity-linked notes ("ELNs")

In order to generate income, the Fund may invest in ELNs. ELNs are investment products that are structured as notes. They are issued by financial institutions such as banks and broker-dealers or entities organized by financial institutions to issue the ELNs. An ELN is designed to offer a return linked to specific economic characteristics identified in the note. The Fund will generally invest in ELNs that are issued in a privately negotiated transaction, including securities offered and sold under Rule 144A of the Securities Act of 1933 (the "Securities Act").

The ELNs in which the Fund invests are derivative instruments. They are designed to replicate a covered call writing strategy by combining into a single note the economic characteristics of (i) an investment in a broad market index and (ii) index covered call writing ("Underlying Characteristics"). The ELNs are expected to provide recurring cash flow to the Fund through this replication. They are expected to be an important source of the Fund's return.

Investing in ELNs may reduce the Fund's volatility. On one hand, the income from the ELNs would reduce potential losses incurred by the Fund's equity portfolio. However, by replicating a covered call strategy in each ELN, the ELNs may also reduce the Fund's ability to fully profit from potential increases in the value of its equity portfolio.

Generally, when purchasing an ELN, the Fund pays the counterparty an amount based on the Underlying Characteristics plus the cost to structure the ELN. Upon maturity of the ELN, the Fund generally receives the par value of the ELN, plus interest, plus or minus a return based on the return of the Underlying Characteristics. However, each ELN will be structured so that it cannot lose more than the principal that the Fund paid when purchasing the ELN; however, in consideration for greater current income or yield, an ELN may be structured such that the Fund may forego its participation in the capital appreciation of the Underlying Characteristics above a predetermined price limit.

Other Investments

The Fund may invest in convertible securities, partnerships, when issued/delayed delivery securities and initial public offerings ("IPOs"). The Fund may also hold cash and cash equivalents.

Principal Investment Risks

The principal risks of investing in the Fund are summarized below. The Fund does not represent a complete investment program. You may lose money by investing in the Fund.

Fund shares are not bank deposits and are not guaranteed, endorsed or insured by the Federal Deposit Insurance Corporation or any other government agency, and are subject to investment risks, including possible loss of the principal invested.

The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund's portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

Market/Issuer Risk: The market value of the Fund's investments will move up and down, sometimes rapidly and unpredictably, based upon overall market and economic conditions, as well as a number of reasons that directly relate to the issuers of the Fund's investments, such as management performance, financial condition and demand for the issuers' goods and services. The Adviser will attempt to reduce this risk by implementing various volatility management strategies and techniques. However, there is no guarantee that such strategies and techniques will produce the intended result.

Equity Securities Risk: The value of the Fund's investments in equity securities could be subject to unpredictable declines in the value of individual securities and periods of below-average performance in individual securities or in the equity market as a whole. Value stocks can perform differently from the

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Fund Summary

market as a whole and from other types of stocks. Value stocks also present the risk that their lower valuations fairly reflect their business prospects and that investors will not agree that the stocks represent favorable investment opportunities, and they may fall out of favor with investors and underperform growth stocks during any given period. Securities issued in IPOs tend to involve greater market risk than other equity securities due, in part, to public perception and the lack of publicly available information and trading history. In the event an issuer is liquidated or declares bankruptcy, the claims of owners of the issuer's bonds generally take precedence over the claims of those who own preferred stock or common stock. Securities of real estate-related companies and REITs in which the Fund may invest may be considered equity securities, thus subjecting the Fund to the risks of investing in equity securities generally.

Credit/Counterparty Risk: Credit/counterparty risk is the risk that the issuer or guarantor of a fixed-income security, or the counterparty to a derivative or other transaction, will be unable or unwilling to make timely payments of interest or principal or to otherwise honor its obligations. As a result, the Fund may sustain losses or be unable or delayed in its ability to realize gains. The Fund will be subject to credit/counterparty risk with respect to its investments in ELNs as well as the counterparties to its derivatives transactions. This risk will be heightened to the extent the Fund enters into derivatives transactions with a single counterparty (or affiliated counterparties that are part of the same organization), causing the Fund to have significant exposure to such counterparty. Many of the protections afforded to participants on organized exchanges and clearing houses, such as the performance guarantee given by a central clearing house, are not available in connection with over-the-counter ("OTC") derivatives transactions, such as foreign currency transactions. For centrally cleared derivatives, such as cleared swaps, futures and many options, the primary credit/counterparty risk is the creditworthiness of the Fund's clearing broker and the central clearing house itself.

Equity-Linked Notes Risk: When the Fund invests in ELNs, it receives cash but limits its opportunity to profit from an increase in the market value of the instrument because of the limits relating to the written index call options exposure replicated within the particular ELN. Investing in ELNs may be more costly to the Fund than if the Fund had invested in the underlying instruments directly. Investments in ELNs often have risks similar to the underlying instruments being replicated, which include market risk. ELNs are derivatives and therefore are subject to derivatives risk. In addition, since ELNs are in note form, ELNs are subject to certain debt securities risks, such as credit and counterparty risk. Should the prices of the underlying instruments move in an unexpected manner, the Fund may not achieve the anticipated benefits of an investment in an ELN, and may realize losses, which could be significant and could include the Fund's entire principal investment in such ELN. Investments in ELNs are also subject to liquidity risk, which may make ELNs difficult to sell and value. A lack of liquidity may also cause the value of the ELN to decline. In addition, ELNs may exhibit price behavior that does not correlate with the underlying securities being replicated. The Fund's ELN investments are subject to the risk that issuers and/or counterparties will fail to make payments when due or default completely, which could result in a loss of all or part of the Fund's investment. Prices of the Fund's ELN investments may be adversely affected if any of the issuers or counterparties it is invested in are subject to an actual or perceived deterioration in their credit quality. As with all investments, successful use of ELNs depends in significant part on the accuracy of the Subadviser's analysis of the issuer's creditworthiness and financial prospects, and of the Subadviser's forecast as to changes in relevant economic and financial market conditions and factors.

Options Risk: The Fund may invest in ELNs that incorporate the characteristics of index call options. The value of the ELNs, and therefore the Fund's, replication of the characteristics of index options will fluctuate in response to changes in the value of the underlying securities. Writing index call options limits the opportunity to profit from an increase in the market value of stocks in exchange for up-front cash at the time of selling the index call option. The Fund may replicate purchasing index call options through its use of ELNs. If it does so, it also risks losing all or part of the cash paid. Unusual market conditions or the lack of a ready market for any particular option at a specific time may reduce the effectiveness of the Fund's option strategies, and for these and other reasons the Fund's option strategies may not reduce the Fund's volatility to the extent desired.

Authorized Participant Concentration Risk: Only an authorized participant ("Authorized Participant") may engage in creation or redemption transactions directly with the Fund. The Fund has a limited number of institutions that act as Authorized Participants, none of which are or will be obligated to engage in creation or redemption transactions. To the extent that these institutions exit the business or are unable to proceed with creation and/or redemption orders with respect to the Fund and no other Authorized Participant is able to step forward to create or redeem Creation Units, the Fund's shares may trade at a discount to net asset value ("NAV") and possibly face trading halts and/or delisting.

Cybersecurity and Technology Risk: The Fund, its service providers, market makers, listing exchange, Authorized Participants and other market participants increasingly depend on complex information technology and communications systems, which are subject to a number of different threats and risks that could adversely affect the Fund and its shareholders. Cybersecurity and other operational and technology issues may result in financial losses to the Fund and its shareholders.

Derivatives Risk: Derivative instruments (such as those in which the Fund may invest, including ELNs) are subject to changes in the value of the underlying assets or indices on which such instruments are based. There is no guarantee that the use of derivatives will be effective or that suitable transactions will be available. Even a small investment in derivatives may give rise to leverage risk and can have a significant impact on the Fund's exposure to securities market values, interest rates or currency exchange rates. It is possible that the Fund's liquid assets may be insufficient to support its obligations under its derivatives positions. The use of derivatives for other than hedging purposes may be considered a speculative activity, and involves greater risks than are involved in hedging. The use of derivatives may cause the Fund to incur losses greater than those that would have occurred had derivatives not been used. The Fund's use of derivatives involves other risks, such as credit/counterparty risk relating to the other party to a derivative contract (which is greater for forward currency contracts, uncleared swaps and other OTC derivatives), the risk of difficulties in pricing and valuation, the risk that changes in the value of a derivative may not correlate as expected with changes in the value of relevant assets, rates or indices, liquidity risk, allocation risk and the risk of losing more than any amounts paid or margin transferred to initiate derivatives positions. There is also the risk that the Fund may be unable to terminate or sell a

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Fund Summary

derivative position at an advantageous time or price. The Fund's derivative counterparties may experience financial difficulties or otherwise be unwilling or unable to honor their obligations, possibly resulting in losses to the Fund.

Index Call Option Risk: As the seller of the index call option, the Fund may write index call options, typically on broad-based securities market indices, with an aggregate notional value less than the market value of its broadly diversified stock portfolio. As the seller of the index call option, the Fund receives cash (the "premium") from the purchaser. The premium, the exercise price and the value of the index determine the gain or loss realized by the Fund as the seller of the index call option. The Fund can also repurchase the call option prior to the expiration date, ending its obligation. In such a case, the difference between the cost of repurchasing the option and the premium received will determine the gain or loss realized by the Fund.

Investments in Other Investment Companies Risk: The Fund will indirectly bear the management, service and other fees of any other investment companies, including ETFs, in which it invests in addition to its own expenses. The Fund's purchases and sales of underlying mutual funds may result in additional transaction costs or tax impacts because of the Fund's structure as an exchange-traded fund that conducts creations and redemptions primarily in-kind.

Issuer Exposure Risk: Although the Fund is "diversified" within the meaning of the Investment Company Act of 1940 (the "1940 Act"), increases in value in certain securities held by the Fund could cause the Fund to be significantly exposed to a relatively small number of issuers. Similarly, although the Fund is not an index fund, in order to reduce the Fund's performance dispersion from its benchmark the Fund may use investments in other investment companies to increase its exposure to certain issuers to a greater extent than might otherwise be permitted under the 1940 Act. This exposure to a relatively small number of issuers could increase the risk and volatility of the Fund.

Large-Capitalization Companies Risk: The securities of large-capitalization companies may be relatively mature compared to smaller companies and therefore subject to slower growth during times of economic expansion. Large-capitalization companies may also be unable to respond quickly to new competitive challenges, such as changes in technology and consumer tastes. The Fund's performance may be adversely affected if securities of large-capitalization companies outperform the market as a whole because although the Fund owns large-capitalization equities through its Equity Portfolio, the Fund also invests in ELNs with short call option spreads on large-capitalization equities (e.g., the S&P 500). Because ELNs generate income from premiums on options sold and are subject to limited upside appreciation given their use of short call option spreads on large-capitalization equities, the outperformance of, or volatility related to, large-capitalization companies may adversely impact the ELN's performance, which in turn may adversely impact Fund performance.

Leverage Risk: Leverage is the risk associated with securities or investment practices (e.g., borrowing and the use of certain derivatives) that multiply small index, market or asset-price movements into larger changes in value. The use of leverage increases the impact of gains and losses on the Fund's returns, and may lead to significant losses if investments are not successful.

Liquidity Risk: Liquidity risk is the risk that the Fund may be unable to find a buyer for its investments when it seeks to sell them or to receive the price it expects. Decreases in the number of financial institutions willing to make markets in the Fund's investments or in their capacity or willingness to transact may increase the Fund's exposure to this risk. Events that may lead to increased redemptions, such as market disruptions or increases in interest rates, may also negatively impact the liquidity of the Fund's investments when it needs to dispose of them. Markets may become illiquid quickly. If the Fund is forced to sell its investments at an unfavorable time and/or under adverse conditions in order to meet redemption requests, such sales could negatively affect the Fund. During times of market turmoil, there may be no buyers or sellers for securities in certain asset classes and dealers may be unwilling or unable to make a market for certain securities. Securities acquired in a private placement, such as securities issued pursuant to Rule 144A under the Securities Act and privately negotiated equity and other investments are generally subject to significant liquidity risk because they are subject to strict restrictions on resale and there may be no liquid secondary market or ready purchaser for such securities. In other circumstances, liquid investments may become illiquid. Derivatives, and particularly over-the-counter ("OTC") derivatives, are generally subject to liquidity risk as well. Liquidity issues may also make it difficult to value the Fund's investments. The Fund may invest in liquid investments that become illiquid due to financial distress, or geopolitical events such as sanctions, trading halts or wars.

Management Risk: A strategy used by the Fund's portfolio managers may fail to produce the intended result.

Market Trading Risk: The Fund faces numerous market trading risks, including the potential lack of an active market for Fund shares or the Fund's underlying portfolio securities, losses from trading in secondary markets, periods of high volatility and disruptions in the creation/redemption process. Any of these factors, among others, may lead to the Fund's shares trading at a premium or discount to NAV. Accordingly, if a shareholder purchases Fund shares at a time when the market price is at a premium to the NAV, or sells shares at a time when the market price is at a discount to the NAV, the shareholder may sustain losses.

Mid-Capitalization Companies Risk: Compared to large-capitalization companies, mid-capitalization companies are more likely to have limited product lines, markets or financial resources. Stocks of these companies often trade less frequently and in limited volume and their prices may fluctuate more than stocks of large-capitalization companies. As a result, it may be relatively more difficult for the Fund to buy and sell securities of mid-capitalization companies.

Models and Data Risk: The Subadviser utilizes various proprietary quantitative models (including models that may utilize forms of artificial intelligence, such as machine learning) to identify investment opportunities. There is a possibility that one or all of the quantitative models may fail to identify profitable opportunities at any time. Furthermore, the models may incorrectly identify opportunities and these misidentified opportunities may lead to substantial losses for the Fund. Models may be predictive in nature and such models may result in an incorrect assessment of future events. Data used in the construction of models may prove to be inaccurate or stale, which may result in losses for the Fund.

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Fund Summary

New and Smaller Sized Fund Risk: The Fund is relatively new and has a limited operating history for investors to evaluate and may not be successful in implementing its investment strategies. The Fund may fail to attract sufficient assets to achieve or maintain economies of scale, which could result in the Fund being liquidated at any time without shareholder approval and at a time that may not be favorable for all shareholders. Smaller ETFs will have a lower public float and lower trading volumes, which can lead to wider bid/ask spreads.

Operational Risk: The Fund is exposed to operational risk arising from a number of factors, including but not limited to human error, processing and communication errors, errors of the Fund's service providers, market makers, listing exchange, Authorized Participants or the issuers of securities in which the Fund invests or with which they do business, failed or inadequate processes and technology or systems failures.

Premium/Discount Risk: Shares of the Fund are listed for trading on the NYSE Arca, Inc. (the "NYSE Arca") and are bought and sold in the secondary market at market prices that may differ from their most recent NAV. The market value of the Fund's shares will fluctuate, in some cases materially, in response to changes in the Fund's NAV, the intraday value of the Fund's holdings, and the relative supply and demand for the Fund's shares on the exchange. Disruptions to creations and redemptions, the existence of extreme market volatility or potential lack of an active trading market for shares may result in shares trading at a significant premium or discount to NAV and/or in a reduced liquidity of your investment. During such periods, you may be unable to sell your shares or may incur significant losses if you sell your shares. There are various methods by which investors can purchase and sell shares and various types of orders that may be placed. Investors should consult their financial intermediary before purchasing or selling shares of the Fund. If a shareholder purchases shares at a time when the market price is at a premium to the NAV or sells shares at a time when the market price is at a discount to the NAV, the shareholder may sustain losses.

Secondary Market Trading Risk: Investors buying or selling shares of the Fund in the secondary market will pay brokerage commissions or other charges imposed by broker-dealers 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 shares.

Trading Issues Risk: Trading in Fund shares on the NYSE Arca may be halted in certain circumstances due to market conditions or for reasons that, in the view of the NYSE Arca, make trading in shares inadvisable. In addition, trading in shares on the NYSE Arca is subject to trading halts caused by extraordinary market volatility pursuant to the NYSE Arca's "circuit breaker" rules (rules that require a halt in trading in a specific period of time when market prices decline by a specified percentage during the course of a trading day). There can be no assurance that the requirements of the NYSE Arca necessary to maintain the listing of the Fund will continue to be met or will remain unchanged.

Valuation Risk: This is the risk that the Fund has valued certain securities or positions at a higher price than the price at which they can be sold. This risk may be especially pronounced for investments, such as derivatives, that may be illiquid or may become illiquid.

Risk/Return Bar Chart and Table

The bar chart and table shown below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's average annual returns for the one-year and life-of-fund periods compare to those of a broad-based securities market index that reflects the performance of the overall market applicable to the Fund. The Fund's past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future. Updated performance information is available online at im.natixis.com and/or by calling the Fund toll-free at 800-862-4863.

To the extent that the shares were subject to the waiver or reimbursement of certain expenses during a period, had such expenses not been waived or reimbursed during the period, total returns would have been lower.

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Fund Summary

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their shares through tax-advantaged arrangements, such as 401(k) plans, qualified plans, education savings accounts, such as 529 plans, or individual retirement accounts. Index performance reflects no deduction for fees, expenses or taxes.

Management

Investment Adviser

Natixis Advisors

Subadviser

Gateway Investment Advisers, LLC ("Gateway")

Portfolio Managers

Daniel M. Ashcraft, CFA^®, Senior Vice President and Portfolio Manager of Gateway, has served as co-portfolio manager of the Fund since 2023.

Michael T. Buckius, CFA^®, Chief Executive Officer and Chief Investment Officer of Gateway, has served as co-portfolio manager of the Fund since 2023.

Kenneth H. Toft, CFA^®, Senior Vice President and Portfolio Manager of Gateway, has served as co-portfolio manager of the Fund since 2023.

Mitchell J. Trotta, CFA^®, Vice President and Portfolio Manager of Gateway, has served as co-portfolio manager of the Fund since 2023.

Purchase and Sale of Fund Shares

The Fund will issue and redeem shares at NAV only in large blocks of shares, typically 10,000 or more shares, called "Creation Units." Only a few financial institutions that are Authorized Participants are authorized to purchase and redeem Creation Units directly with the Fund. Creation Units are typically issued and redeemed in exchange for cash and/or the deposit or delivery of a basket of securities specified each day by the Fund as the securities in exchange for which the Fund will issue or redeem shares. Except when aggregated in Creation Units, shares are not redeemable securities of the Fund. The number of shares comprising a Creation Unit may change from time to time.

Individual shares of the Fund may only be purchased and sold in secondary market transactions through broker-dealers. Shares of the Fund are listed for trading on the NYSE Arca, and because shares trade at market prices rather than NAV, shares of the Fund may trade at a price greater than NAV (a premium) or less than NAV (a discount).

You may incur costs attributable to the difference between the highest price a buyer is willing to pay to purchase shares of the Fund (bid) and the lowest price a seller is willing to accept for shares of the Fund (ask) when buying or selling shares in the secondary market ("the bid/ask spread"). For more information, including recent information (when available) regarding the Fund's NAV, market price, premiums and discounts, and bid/ask spreads, please visit the Fund's website at im.natixis.com.

Tax Information

Fund distributions are generally taxable to you as ordinary income or capital gains, except for distributions to retirement plans and other investors that qualify for tax-advantaged treatment under U.S. federal income tax law generally. Investments through such tax-advantaged plans will generally be taxed only upon withdrawal of monies from the tax-advantaged arrangement.

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 the 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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