Mutual Fund Summary Prospectus (497k)

Summary Prospectus May 1, 2012, as revised November 21, 2012

ASG Diversifying Strategies Fund Ticker Symbol: Class A (DSFAX), Class C (DSFCX) and Class Y (DSFYX)

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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 ngam.natixis.com/funddocuments. You can also get this information at no cost by calling 800-225-5478 or by sending an e-mail request to [e-mail]. The Fund’s Prospectus and Statement of Additional Information, each dated May 1, 2012 are incorporated by reference into this Summary Prospectus.

Investment Goal

The Fund pursues an absolute return strategy that seeks to provide capital appreciation. The secondary goal of the Fund is to achieve these returns while maintaining a low or negative correlation over time with the returns of major equity indices.

Fund Fees & Expenses

The following table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the Natixis Fund Complex. More information about these and other discounts is available from your financial professional and in the section “How Sales Charges Are Calculated” on page 70 of the Prospectus and on page 103 in the section “Reduced Sales Charges” of the Statement of Additional Information (“SAI”).

Shareholder Fees (fees paid directly from your investment)	Class A	Class C	Class Y
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	5.75%	None	None
Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, as applicable)	None	1.00%	None
Redemption fees	None	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)	Class A	Class C	Class Y
Management fees	1.25%	1.25%	1.25%
Distribution and/or service (12b-1) fees	0.25%	1.00%	0.00%
Other expenses	0.30%	0.30%	0.30%
Total annual fund operating expenses	1.80%	2.55%	1.55%
Fee waiver and/or expense reimbursement 1	0.08%	0.08%	0.08%
Total annual fund operating expenses after fee waiver and/or expense reimbursement	1.72%	2.47%	1.47%

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods (except where indicated). The example 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 Total Annual Fund Operating Expenses After Fee Waiver and/or Expense Reimbursement for the first year and on the Total Annual Fund Operating Expenses for the remaining years. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

If shares are redeemed:
	1 year	3 years	5 years	10 years
Class A	$740	$1,102	$1,487	$2,563
Class C	$350	$786	$1,348	$2,879
Class Y	$150	$482	$837	$1,839

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If shares are not redeemed:
	1 year	3 years	5 years	10 years
Class C	$250	$786	$1,348	$2,879

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AlphaSimplex Group, LLC (“AlphaSimplex” or the “Adviser”) has given a binding contractual undertaking to the Fund to limit the amount of the Fund’s total annual fund operating expenses to 1.70%, 2.45% and 1.45% of the Fund’s average daily net assets for Class A, C and Y shares, respectively, exclusive of brokerage expenses, interest expense, taxes, acquired fund fees and expenses, organizational and extraordinary expenses, such as litigation and indemnification expenses. This undertaking is in effect through April 30, 2013 and may be terminated before then only with the consent of the Fund’s Board of Trustees. The Adviser will be permitted to recover, on a class by class basis, management fees waived and/or expenses reimbursed to the extent that expenses in later periods fall below 1.70%, 2.45% and 1.45% of the Fund’s average daily net assets for Class A, C and Y shares, respectively. The Fund will not be obligated to repay any such waived/reimbursed fees and expenses more than one year after the end of the fiscal year in which the fee/expense was waived/reimbursed.

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. Due to the short-term nature of the Fund’s investment portfolio, the Fund does not calculate a portfolio turnover rate.

Investments, Risks and Performance

Principal Investment Strategies

The Fund seeks to generate positive absolute returns over time rather than track the performance of any particular index. In selecting investments for the Fund, the Adviser uses multiple quantitative investment models and strategies (for example, relative value fixed income strategies and multi-market trend strategies) each of which has an absolute return objective. Each model and strategy may involve a broad range of market exposures. These models may include, for example, models that base investment decisions on fixed income spreads and models which seek to identify trends across various asset classes. The Adviser uses quantitative and qualitative judgments in the determination of weighting among the models and strategies. Although the Fund seeks positive absolute returns over time, it is likely that the Fund’s investment returns may be volatile over short periods of time. The Fund may outperform the overall securities market during periods of flat or negative market performance and may underperform during periods of strong market performance. There can be no assurance that the Fund’s returns over time or during any period will be positive or that the Fund will outperform the overall security markets over time or during any particular period.

Under normal market conditions, the Adviser typically will make extensive use of a variety of derivative instruments, in particular futures and forward contracts, to capture the exposures suggested by its absolute return strategies while also adding value through volatility management and correlation management. These market exposures, which are expected to change over time, may include, for example, exposures to the returns of equity and fixed income securities, currencies and commodities. The Adviser will scale the notional exposure of the Fund’s futures and currency forward positions with the objective of targeting a relatively stable level of annualized volatility for the Fund’s overall portfolio. The Adviser may also use exchange-traded futures contracts on broad U.S. or international equity indices to decrease any undesired correlation with the returns of the major equity indices. The Adviser will have great flexibility to allocate the Fund’s derivatives exposure among various securities, indices, currencies, commodities and other instruments; the amount of the Fund’s assets that may be allocated to derivative strategies and among these various instruments is expected to vary over time. When buying and selling securities and other instruments for the Fund, and in determining the amount of assets to be allocated to the Money Market Portion (as defined below), the Adviser will also consider the following factors: (i) the Fund’s obligations under its various derivative positions; (ii) redemption requests; (iii) yield management; (iv) credit management and (v) volatility management. The Fund may invest in non-U.S. securities and instruments and securities and instruments traded outside the United States and expects to engage in non-U.S. currency transactions.

Under normal market conditions, it is expected that no more than 25% of the Fund’s total assets will be dedicated to initial and variation margin payments relating to the Fund’s derivative transactions. The gross notional value of the Fund’s derivative investments, however, will generally exceed 25% of the Fund’s total assets, and may significantly exceed the total value of the Fund’s assets. The Fund expects that under normal market conditions it will invest at least 75% of its total assets in money market and other short-term, high quality securities (the “Money Market Portion”) managed by Reich & Tang Asset Management, LLC (the “Subadviser”), although the Fund may invest less than this percentage. The Adviser will determine the percentage of the Fund’s assets that will be invested in the Money Market Portion at any time. The assets allocated to the Money Market Portion will be used primarily to support the Fund’s investments in derivatives and similar instruments and, secondarily, to provide the Fund with incremental income and liquidity. Although the Fund will invest a significant portion of its assets in money market instruments, the Fund is not a “money market” fund and the value of the Money Market Portion as well as the value of the Fund’s shares may decrease. The Fund is not subject to the portfolio quality, maturity and net asset value requirements applicable to money market funds, and the Fund will not seek to maintain a stable net asset value.

The Subadviser will only invest the assets of the Money Market Portion in high quality securities which are denominated in U.S. dollars, and will select securities for investment based on various factors, including the security’s maturity and rating. The Subadviser will invest primarily in (i) short-term obligations issued or guaranteed by the United States government, its agencies or instrumentalities (“U.S. Government Obligations”); (ii) securities issued by foreign governments, their political subdivisions, agencies or instrumentalities; (iii) certificates of deposit, time deposits and bankers’ acceptances issued

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by domestic banks, foreign branches of domestic banks, foreign subsidiaries of domestic banks, and domestic and foreign branches of foreign banks; (iv) variable amount master demand notes; (v) participation interests in loans extended by banks to companies; (vi) commercial paper or similar debt obligations; and (vii) repurchase agreements.

Although the Fund does not intend to invest in physical commodities directly, the Fund expects to obtain investment exposure to commodity-related derivatives through a wholly-owned subsidiary organized under the laws of the Cayman Islands that will make commodity-related investments (the “Commodity Subsidiary”). Under normal market conditions, no more than 10% of the Fund’s total assets will be dedicated to initial and variation margin payments relating to these transactions.

The Fund will concentrate its investments in the financial services industry, which means it will normally invest at least 25% of its total assets in securities and other obligations (for example, bank certificates of deposit) of issuers in such industry.

The Fund may engage in active and frequent trading of securities and other instruments. Effects of frequent trading may include high transaction costs, which may lower the Fund’s return, and realization of greater short-term capital gains, distributions of which are taxable as ordinary income to taxable shareholders. Trading costs and tax effects associated with frequent trading may adversely affect the Fund’s performance. Due to the short-term nature of the Fund’s investment portfolio, the Fund does not calculate a portfolio turnover rate. The Fund’s trading in derivatives is active and frequent. Active and frequent trading of derivatives, like active and frequent trading of securities, will result in transaction costs which reduce fund returns.

The percentage limitations set forth herein are not investment restrictions and the Fund may exceed these limits from time to time.

Principal 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.

Allocation and Correlation Risk: This is the risk that the Adviser’s judgments about, and allocations between, asset classes and market exposures may adversely affect the Fund’s performance. This risk can be increased by the use of derivatives to increase allocations to various market exposures. This is because derivatives can create investment leverage, which will magnify the impact to the Fund of its investment in any underperforming market exposure.

Commodity Risk: This is the risk that exposure to the commodities markets may subject the Fund to greater volatility than investments in traditional securities. The value of physical commodities or commodity-linked derivative instruments may be affected by changes in overall market movements, commodity price volatility, changes in interest rates, currency fluctuations, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, embargoes, tariffs and international economic, political and regulatory developments. Recent rulemaking by the Commodity Futures Trading Commission (“CFTC”) may affect the Fund’s ability to pursue its investment strategies or increase the Fund’s expenses. As of the date of this prospectus, the potential impact of the new CFTC rules on the Fund is uncertain.

Commodity Subsidiary Risk: Investing in the Commodity Subsidiary will indirectly expose the Fund to the risks associated with the Commodity Subsidiary’s investments, such as commodity investment risk. The Commodity Subsidiary is not registered under the Investment Company Act of 1940 (the “1940 Act”) and is not subject to all of the investor protections of the 1940 Act. Recent rulemaking by the CFTC may affect the Fund’s ability to use the Commodity Subsidiary to pursue its investment strategies. As of the date of this prospectus, the potential impact of the new CFTC rules on the Fund is uncertain. Changes in the laws of the United States and/or the Cayman Islands, under which the Fund and the Commodity Subsidiary, respectively, are organized, could negatively affect the Fund and its shareholders.

Concentrated Investment Risk: The Fund is particularly vulnerable to events affecting companies in the financial services industry because the Fund concentrates its investments in securities and other obligations of issuers in such industry. Examples of risks affecting the financial services industry include changes in governmental regulation, issues relating to the availability and cost of capital, changes in interest rates and/or monetary policy and price competition. In addition, financial services companies are often more highly leveraged than other companies, making them inherently riskier. As a result, the Fund’s shares may rise and fall in value more rapidly and to a greater extent than shares of a fund that does not concentrate or focus in a particular industry or economic sector. The financial services industry has recently experienced high volatility and a number of issuer failures and the value of many of these securities has significantly declined. As a result, the risk associated with investing in the Fund may be increased as compared to a fund that does not concentrate in the financial services industry.

Credit/Counterparty Risk: Credit risk is the risk that the issuer or the guarantor of a fixed-income security, or the counterparty to a derivatives or other transaction, will be unable or unwilling to make timely payments of interest or principal or to otherwise honor its obligations. The Fund will be subject to credit risks with respect to the counterparties of its derivative transactions. Many of the protections afforded to participants on organized exchanges, such as the performance guarantee of an exchange clearing house, are not available in connection with over-the-counter (“OTC”) derivative transactions, such as foreign currency transactions. As a result, in instances when the Fund enters into OTC derivative transactions, the Fund will be subject to the risk that its direct counterparties will not perform their obligations under the transactions and that the Fund will sustain losses or be unable to realize gains.

Currency Risk: Fluctuations in the exchange rates between different currencies may negatively affect an investment. The Fund may elect not to hedge currency risk, or may hedge such risk imperfectly, which may cause the Fund to incur losses that would not have been incurred had the risk been hedged.

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Derivatives Risk: Derivatives are subject to changes in the value of the underlying asset or indices on which such transactions 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 markets 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 which would have occurred had derivatives not been used. The Fund’s use of derivatives, such as futures, forward contracts, and other foreign currency transactions and commodity-linked derivatives involves other risks, such as the credit risk relating to the other party to a derivative contract (which is greater for forward contracts 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 perfectly with relevant assets, rates or indices, liquidity risk, allocation risk and the risk of losing more than the initial margin required to initiate derivatives positions. There is also the risk that the Fund may be unable to terminate or sell a derivatives position at an advantageous time or price. Moreover, a number of broker-dealers and other financial institutions have recently experienced extreme financial difficulty, sometimes resulting in bankruptcy of the institution. There can be no assurance that the Fund’s derivative counterparties will be able to avoid experiencing similar financial difficulties, possibly resulting in losses to the Fund.

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. In the event an issuer is liquidated or declares bankruptcy, the claims of owners of the issuer’s bonds and preferred stock generally take precedence over the claims of those who own common stock.

Foreign Securities Risk: Investments in foreign securities may be subject to greater political, economic, environmental, credit and information risks. The Fund’s investments in foreign securities are subject to foreign currency fluctuations. Foreign securities may be subject to higher volatility than U.S. securities, varying degrees of regulation and limited liquidity.

Interest Rate Risk: Changes in interest rates may cause the value of the Fund’s investments to decrease. Generally, the value of fixed-income securities rises when prevailing interest rates fall and falls when interest rates rise. A period of low interest rates may cause the Fund to have a low or negative yield, potentially reducing the value of your investment.

Issuer Risk: The value of the Fund’s investments may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods and services.

Leverage Risk: Use of derivative instruments may involve leverage. Leverage is the risk associated with securities or practices that multiply small index, market or asset price movements into larger changes in value. To the extent that the Fund uses a derivative for purposes other than as a hedge, or if the Fund hedges imperfectly, the Fund is directly exposed to the risks of that derivative and any loss generated by the derivative will not be offset by a gain. The use of leverage increases the impact of gains and losses on a fund’s returns, and may lead to significant losses if investments are not successful. However, the Adviser will attempt to ensure that at all times the Fund has sufficient liquid assets to enable it to satisfy its obligations under its derivative contracts.

Liquidity Risk: Liquidity risk exists when particular investments are difficult to purchase or sell, possibly preventing the Fund from selling these illiquid securities at an advantageous price or time. A lack of liquidity also may cause the value of investments to decline. Illiquid investments also may be difficult to value.

Management Risk: A strategy used by the Fund’s portfolio managers may fail to produce the intended result. The Adviser utilizes various proprietary quantitative models 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, they may incorrectly identify opportunities and these misidentified opportunities may lead to substantial losses.

Market Risk: The market value of a security will move up and down, sometimes rapidly and unpredictably, based upon a change in an issuer’s financial condition, as well as overall market and economic conditions. The Fund’s portfolio managers 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.

U.S. Government Securities Risk: Investments in certain U.S. government securities may not be supported by the full faith and credit of the U.S. government. Accordingly, no assurance can be given that the U.S. government will provide financial support to U.S. government agencies, instrumentalities or sponsored enterprises if it is not obligated to do so by law. The maximum potential liability of the issuers of some U.S. government securities held by the Fund may greatly exceed their current resources, and it is possible that these issuers will not have the funds to meet their payment obligations in the future. In such a case, the Fund would have to look principally to the agency, instrumentality or sponsored enterprise issuing or guaranteeing the security for ultimate repayment, and the Fund may not be able to assert a claim against the U.S. government itself in the event the agency, instrumentality or sponsored enterprise does not meet its commitment. Concerns about the capacity of the U.S. government to meet its obligations may raise the interest rates payable on its securities, negatively impacting the price of such securities already held by the Fund.

Valuation Risk: This is the risk that the Fund has valued certain securities 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.

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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 with those of two broad measures of market performance. 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 ngam.natixis.com and/or by calling the Fund toll-free at 800-225-5478.

The bar chart does not reflect any sales charge that you may be required to pay when you buy or redeem the Fund’s shares. A sales charge will reduce your return.

Total Returns for Class A

		Highest Quarterly Return: Third Quarter 2010, 13.89%
		Lowest Quarterly Return: Fourth Quarter 2010, -4.18%

Average Annual Total Returns (for the periods ended December 31, 2011)	Past 1 Year	Life of Fund (8/3/09)
ASG Diversifying Strategies Fund Class A – Return Before Taxes	-8.36%	2.70%
Return After Taxes on Distributions	-9.66%	0.79%
Return After Taxes on Distributions & Sale of Fund Shares	-5.44%	1.34%
Class C – Return Before Taxes	-4.37%	4.44%
Class Y – Return Before Taxes	-2.48%	5.46%
3-month London Interbank Offered Rate (LIBOR) (Calculated from August 1, 2009) 1	0.27%	0.33%
Barclay Fund of Funds Index (Calculated from August 1, 2009) 2	-6.22%	1.04%
HFRI Fund of Funds Composite Index (Calculated from August 1, 2009)	-5.72%	1.63%

1	Prior to May 1, 2012, the Fund’s prospectus listed the Fund’s primary benchmark as HFRI Fund of Funds Composite Index, an unmanaged, equally-weighted hedge fund index. 3-month London Interbank Offered Rate (LIBOR) is now listed as the Fund’s primary benchmark because AlphaSimplex believes that 3-month LIBOR provides an appropriate comparison in light of the Fund’s absolute return strategy.
2	Effective November 19, 2012 the Barclay Fund of Funds Index replaced the HFRI Fund of Funds Composite Index as the Fund’s secondary benchmark because AlphaSimplex believes the index is an appropriate representation of hedge fund industry performance.

Prior to May 1, 2012, Class Y shares were offered in a separate prospectus and given that Class Y shares are now offered in this multi-class prospectus, Total Returns, Return After Taxes on Distributions and Return After Taxes on Distributions & Sale of Fund Shares are now presented for Class A Shares.

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 Fund shares through tax-deferred arrangements, such as 401(k) plans, qualified plans, education savings accounts, such as 529 plans, or individual retirement accounts. The after-tax returns are shown for only one class of the Fund. After-tax returns for the other classes of the Fund will vary. Index performance reflects no deduction for fees, expenses, or taxes. The Return After Taxes on Distributions & Sale of Fund Shares for the one-year period exceeds the Return Before Taxes due to an assumed benefit from losses on a sale of Fund shares at the end of the measurement period.

Management

Investment Adviser

AlphaSimplex Group, LLC

Investment Subadviser

Reich & Tang Asset Management, LLC

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Portfolio Managers

Andrew W. Lo, Chief Investment Strategist of the Adviser, has served as co-portfolio manager of the Fund since 2009.

Jeremiah H. Chafkin, President of the Adviser, has served as co-portfolio manager of the Fund since 2009.

Philippe P. Lüdi, Vice President of the Adviser, has served as co-portfolio manager of the Fund since 2010.

Robert S. Rickard, Senior Vice President and head of Portfolio Management and Trading of the Subadviser, has served as co-portfolio manager of the Fund since 2009.

Purchase and Sale of Fund Shares

Class A and Class C Shares

The following chart shows the investment minimums for various types of accounts:

Type of Account	Minimum Initial Purchase	Minimum Subsequent Purchase
Any account other than those listed below	$2,500	$100
For shareholders participating in Natixis Funds’ Investment Builder Program	$1,000	$50
For Traditional IRA, Roth IRA, Rollover IRA, SEP-IRA and Keogh plans using the Natixis Funds’ prototype document (direct accounts, not held through intermediary)	$1,000	$100
Coverdell Education Savings Accounts	$500	$100

Class Y Shares

Class Y shares of the Fund may be purchased by the following entities at the following investment minimums.

A minimum initial investment of $100,000 and the minimum subsequent investment of $100 for:

• Other mutual funds, endowments, foundations, bank trust departments or trust companies.

There is no initial or subsequent investment minimum for:

• Wrap Fee Programs of certain broker-dealers, the advisers or NGAM Distribution, L.P. (the “Distributor”). Please consult your financial representative to determine if your wrap fee program is subject to additional or different conditions or fees.
• Retirement Plans such as 401(a), 401(k) or 457 plans.
• Certain Individual Retirement Accounts if the amounts invested represent rollover distributions from investments by any of the retirement plans invested in the Fund.
• Registered Investment Advisers investing on behalf of clients in exchange for an advisory, management or consulting fee.
• Fund Trustees , former Fund trustees, employees of affiliates of the Natixis Funds and other individuals who are affiliated with any Natixis Fund (this also applies to any spouse, parents, children, siblings, grandparents, grandchildren and in-laws of those mentioned) and Natixis affiliate employee benefit plans.

Due to operational limitations at your financial intermediary, certain wrap fee programs, retirement plans, individual retirement accounts and accounts of registered investment advisers may be subject to the investment minimums described above.

The Fund’s shares are available for purchase (and are redeemable on any business day) through your investment dealer, directly from the Fund by writing to the Fund at Natixis Funds, P.O. Box 219579, Kansas City, MO 64121-9579, by exchange, by wire, by internet at ngam.natixis.com, through the Automated Clearing House system, or, in the case of redemptions, by telephone at 800-225-5478 or by the Systematic Withdrawal Plan.

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-exempt treatment under U.S. federal income tax law generally. Investments in such tax-advantaged plans will generally be taxed only upon withdrawal of monies from the tax-exempt arrangement.

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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.

UADS77-0512

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