Strategy. Under normal circumstances, the Fund will invest at least 80% of its assets in equity securities. Equity securities may include exchange-traded common stocks and exchange-traded preferred stocks. Under normal circumstances, the Fund will invest at least 80% of its assets in securities of U.S. issuers. The Funds approach to equity investing combines the styles of two subadvisers in selecting securities for each of the Funds segments. The segments and their subadvisers are listed below. Harris Associates - Large Cap Value segment - Under normal circumstances, the Large Cap Value segment of the Fund managed by Harris Associates L.P. (Harris Associates) will invest primarily in the exchange-traded common stocks of larger-capitalization companies that Harris Associates believes are trading at a substantial … Show more… Under normal circumstances, the Fund will invest at least 80% of its assets in equity securities. Equity securities may include exchange-traded common stocks and exchange-traded preferred stocks. Under normal circumstances, the Fund will invest at least 80% of its assets in securities of U.S. issuers. The Funds approach to equity investing combines the styles of two subadvisers in selecting securities for each of the Funds segments. The segments and their subadvisers are listed below. Harris Associates - Large Cap Value segment - Under normal circumstances, the Large Cap Value segment of the Fund managed by Harris Associates L.P. (Harris Associates) will invest primarily in the exchange-traded common stocks of larger-capitalization companies that Harris Associates believes are trading at a substantial discount to the companys intrinsic value. By intrinsic value, Harris Associates means its estimate of the price a knowledgeable buyer would pay to acquire the entire business. Harris Associates believes that investing in securities priced significantly below what Harris Associates believes is a companys intrinsic value presents the best opportunity to achieve the Funds investment objectives. Harris Associates usually sells a security when the price approaches its estimated value and monitors each holding and adjusts its price targets as warranted to reflect changes in the issuers fundamentals. In determining whether an issuer is a U.S. or foreign issuer for the Harris Associates Large Cap Value segment, Harris Associates considers various factors, including its country of domicile, the primary stock exchange on which it trades, the location from which the majority of its revenue comes, and its reporting currency. Loomis Sayles - All Cap Growth segment - Under normal circumstances, the All Cap Growth segment of the Fund, managed by Loomis, Sayles & Company, L.P. (Loomis Sayles), will invest primarily in exchange-traded equity securities, including exchange-traded common stocks and exchange-traded American Depositary Receipts (ADRs). This segment may invest in companies of any size. The segment normally invests across a wide range of sectors and industries. The segments portfolio manager employs a growth style of equity management that emphasizes companies with sustainable competitive advantages versus others, long-term structural growth drivers that will lead to above-average future cash flow growth, attractive cash flow returns on invested capital, and management teams focused on creating long-term value for shareholders. The segments portfolio manager aims to invest in companies when they trade at a significant discount to the estimate of intrinsic value (i.e., companies with share prices trading significantly below what the portfolio manager believes the share price should be). The segment will consider selling a portfolio investment when the portfolio manager believes an unfavorable structural change occurs within a given business or the markets in which it operates, a critical underlying investment assumption is flawed, when a more attractive reward-to-risk opportunity becomes available, when the portfolio manager believes the current price fully reflects intrinsic value, or for other investment reasons which the portfolio manager deems appropriate. Although certain equity securities purchased by the Loomis Sayles All Cap Growth segment of the Fund may be issued by domestic companies incorporated outside of the United States, Loomis Sayles does not consider these securities to be foreign if they are included in the U.S. equity indices published by S&P Global Ratings or Russell Investments or if the securitys country of risk defined by Bloomberg is the United States. Subject to the allocation policy adopted by the Funds Board of Trustees, Natixis Advisors generally allocates capital invested in the Fund equally (i.e., 50%) between its two segments. Under the allocation policy, Natixis Advisors may also allocate capital away from or towards each segment from time to time and may reallocate capital between the segments. Each subadviser manages its segment of the Funds assets in accordance with its distinct investment style and strategy. Non-Transparent ETF with Proxy Portfolio Structure. The Fund is a type of exchange traded fund (ETF). Unlike traditional ETFs, however, which generally publish their portfolio holdings on a daily basis, the Fund discloses a portfolio transparency substitutethe Proxy Portfolioand certain related information about the relative performance of the Proxy Portfolio and the Funds actual portfolio (Actual Portfolio) holdings (the Proxy Portfolio Disclosures), which are intended to help keep the market price of the Funds shares trading at or close to the underlying net asset value (NAV) per share of the Fund. While the Proxy Portfolio includes some of the Funds holdings, it is not the Funds Actual Portfolio, and the Fund will not disclose the daily holdings of the Actual Portfolio. Although the Fund seeks to benefit from keeping its portfolio information secret, market participants may attempt to use the Proxy Portfolio to identify the Funds trading strategy, which if successful, could result in such market participants engaging in certain predatory trading practices that may have the potential to harm the Fund and its shareholders. The Funds exemptive relief limits the types of securities in which the Fund can invest, which may constrain the Funds ability to implement its investment strategies. The Fund is actively-managed and does not intend to track an index. Show less