Summary Prospectus by Investment Company (Form 497K)

Eaton Vance All Asset Strategy Fund

This Summary Prospectus is designed to provide investors with key fund information in a clear and concise format. Before you invest, you may want to review the Fund's Prospectus and Statement of Additional Information, which contain more information about the Fund and its risks. The Fund's Prospectus and Statement of Additional Information, both dated January 1, 2026, as may be amended or supplemented, are incorporated by reference into this Summary Prospectus. For free paper or electronic copies of the Fund's Prospectus, Statement of Additional Information, annual and semi-annual shareholder reports, and other information about the Fund, go to  http://www.eatonvance.com/funddocuments, email a request to [email protected], call 1-800-262-1122, or ask any financial advisor, bank, or broker-dealer who offers shares of the Fund. Unless otherwise noted, page number references refer to the current Prospectus for this Fund.

Investment Objective

The Fund's investment objective is to seek total return.

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. Investors may also pay commissions or other fees to their financial intermediary, which are not reflected below. You may qualify for a reduced sales charge on purchases of Class A shares if you invest, or agree to invest over a 13-month period, at least $50,000 in Eaton Vance  funds. Certain financial intermediaries also may offer variations in Fund sales charges to their customers as described in Appendix A - Financial Intermediary Sales Charge Variations in the Fund's Prospectus. More information about these and other discounts is available from your financial intermediary and in Sales Charges beginning on page 44 of the Fund's Prospectus and page 21  of the Fund's Statement of Additional Information.

Shareholder Fees (fees paid directly from your investment)

Eaton Vance All Asset Strategy Fund   | Fund Summary

Eaton Vance All Asset Strategy Fund (Con't)

Annual Fund Operating Expenses (expenses you pay each year as a percentage of the value of your investment)

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Eaton Vance All Asset Strategy Fund (Con't)

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. The Example also assumes that your investment has a 5% return each year, that the operating expenses remain the same and that any expense reimbursement arrangement remains in place for the contractual period. 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" the 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. During the most recent fiscal year, the Fund's portfolio turnover rate was 76% of the average value of its portfolio.

Principal Investment Strategies

In seeking its investment objective, the Fund has the flexibility to allocate its assets in markets around the world and among various asset classes, including equity, fixed-income, commodity, currency and cash investments.

The Fund seeks to achieve diversified, superior risk adjusted returns by dynamically allocating to multiple strategies, regions, sectors and factors in a changing and diverse growth cycle. Value is added through combining efficient market exposure with active management alpha through tactical opportunities in navigating markets and efficient implementation. The adviser's asset allocation methodology is differentiated using a top-down approach to find value and drive alpha. The adviser seeks to increase upside vs. downside capture throughout economic cycles to produce stable returns that compound. The adviser believes markets move with economic tides, at the heart of which is global gross domestic product growth and that growth is unevenly distributed across asset classes, sectors, sub-sectors and regions, creating investment opportunities. In selecting securities and other instruments, the portfolio managers employ quantitative screening and optimization tools to achieve desired market exposures while seeking to manage security-specific and other observable market risks. The portfolio is monitored on an ongoing basis and rebalanced as necessary to seek to ensure that desired market exposures and risk parameters are maintained. Securities may be sold if they exhibit performance that might counteract the desired exposures or to implement a revised allocation. A security may also be sold if the adviser believes it exhibits unusual volatility or price movement.

The Fund currently expects to invest, under normal circumstances, 0-80% of its net assets in equity securities, 20-90% in fixed-income securities and other fixed and floating-rate income instruments, 0-25% in commodities and/or currencies, and 0-25% in cash and cash equivalents. The Fund may primarily utilize pooled investment vehicles including exchange traded funds ("ETFs") and open-ended registered investment companies to gain exposure to certain asset classes or segments of asset classes, including fixed income, commodities, and certain equity sectors. The Fund may also invest in derivatives (as described below) to obtain such exposures. To the extent the Fund holds cash as collateral for derivatives, or enters into forward foreign currency exchange contracts to hedge current portfolio holdings, the ranges described above may be exceeded. The expected long-term (over a true secular cycle of at least 10 years) target allocation of the Fund is 40% in fixed-income securities and 60% in equity securities. There is no requirement to manage the Fund within this target allocation. The Fund's actual asset allocation may be materially different depending on market conditions, and the Fund's asset allocation over shorter or longer market cycles may differ materially from the target.

The Fund may invest without limit in both developed and emerging markets, including frontier markets. Such investments may include securities denominated in foreign currencies and securities trading in the form of depositary receipts, including American Depositary Receipts ("ADRs"), which are either sponsored or unsponsored, and Global Depositary Receipts. The Fund may invest in fixed-income securities of any credit quality including securities rated below investment grade and comparable unrated securities ("junk"), and expects to invest principally in fixed-income securities that are issued by corporations, issued or guaranteed by the U.S. government or its agencies or instrumentalities, obligations of other sovereign nations, municipal obligations, mortgage-backed and asset-backed

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securities, inflation-linked debt securities or zero coupon bonds. The Fund may also invest in senior loans and variable rate obligations. The Fund may invest in stocks of companies of any capitalization, publicly traded real estate investment trusts ("REITs") and exchange-traded notes ("ETNs"). The Fund may invest in ETFs and open-ended registered investment companies, in order to manage cash positions or seek exposure to certain markets or market sectors. Investment in cash or cash equivalents may include U.S. and foreign bank certificates of deposit, fixed time deposits, repurchase agreements, bankers' acceptances and other short-term instruments with a remaining maturity of 397 days or less.

The Fund may engage in derivative transactions to seek return, to seek to hedge against fluctuations in securities prices, interest rates or currency exchange rates, to change the effective duration of the fixed-income securities in its portfolio, to manage certain investment risks and/or as a substitute for the purchase or sale of securities, currencies or commodities. The Fund expects to use derivatives principally when seeking to gain exposure to equity or fixed-income securities using futures contracts on securities indices and/or when seeking to gain or reduce exposure to certain currencies by buying or selling forward foreign currency exchange contracts, but may also purchase or sell forwards or other types of futures contracts; options on futures contracts; exchange-traded and over-the-counter options; equity collars, equity-linked securities and equity swap agreements; interest rate, total return, inflation and credit default swaps; forward rate agreements; and credit linked notes and other similarly structured products. The Fund may also engage in covered short sales (on individual securities held or on an index or basket of securities whose constituents are held in whole or in part or for which liquid assets have been segregated) and forward commitments. Except as required by applicable regulation, there is no stated limit on the Fund's use of derivatives for such purposes. The Fund may also lend its securities.

Principal Risks

Market Risk. The value of investments held by the Fund may increase or decrease in response to social, economic, political, financial, public health crises or other disruptive events (whether real, expected or perceived) in the U.S. and global markets and include events such as war, natural disasters, epidemics and pandemics, terrorism, conflicts and social unrest. These events may negatively impact broad segments of businesses and populations and may exacerbate pre-existing risks to the Fund. The frequency and magnitude of resulting changes in the value of the Fund's investments cannot be predicted. Certain securities and other investments held by the Fund may experience increased volatility, illiquidity, or other potentially adverse effects in reaction to changing market conditions. Monetary and/or fiscal actions taken by U.S. or foreign governments to stimulate or stabilize the global economy may not be effective and could lead to high market volatility. No active trading market may exist for certain investments held by the Fund, which may impair the ability of the Fund to sell or to realize the current valuation of such investments in the event of the need to liquidate such assets.

Equity Securities Risk. The value of equity securities and related instruments may decline in response to adverse changes in the economy or the economic outlook; deterioration in investor sentiment; interest rate, currency, and commodity price fluctuations; adverse geopolitical, social or environmental developments; issuer and sector-specific considerations; unexpected trading activity among retail investors; or other factors. Market conditions may affect certain types of stocks to a greater extent than other types of stocks. If the stock market declines in value, the value of the Fund's equity securities will also likely decline. Although prices can rebound, there is no assurance that values will return to previous levels.

Foreign Investment Risk. Foreign investments can be adversely affected by political, economic and market developments abroad, including the imposition of economic and other sanctions by the United States or another country against a particular country or countries, organizations, entities and/or individuals. There may be less publicly available information about foreign issuers because they may not be subject to reporting practices, requirements or regulations comparable to those to which United States companies are subject. Adverse changes in investment regulations, capital requirements or exchange controls could adversely affect the value of the Fund's investments. Foreign markets may be smaller, less liquid and more volatile than the major markets in the United States and, as a result, Fund share values may be more volatile. Trading in foreign markets typically involves higher expense than trading in the United States. The Fund may have difficulties enforcing its legal or contractual rights in a foreign country. Depositary receipts are subject to many of the risks associated with investing directly in foreign instruments, including the political and economic risks of the underlying issuer's country and, in the case of depositary receipts traded on foreign markets, currency risk.

Economic data as reported by sovereign entities may be delayed, inaccurate or fraudulent. In the event of a default by a sovereign entity, there are typically no assets to be seized or cash flows to be attached. Furthermore, the willingness or ability of a sovereign entity to restructure defaulted debt may be limited. Therefore, losses on sovereign defaults may far exceed the losses from the default of a similarly rated  U.S. debt issuer.

Emerging Markets Investment Risk. Investment markets within emerging market countries are typically smaller, less liquid, less developed and more volatile than those in more developed markets like the United States, and may be focused in certain sectors. Emerging market securities often involve greater risks than developed market securities. The information available about an emerging market issuer may be less reliable than for comparable issuers in more developed capital markets. Such risks may be greater in frontier markets.

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Frontier Market Investment Risk. Frontier markets are among the smallest and least mature investment markets. Frontier market countries may have greater political or economic instability and may also be subject to trade barriers, adjustments in currency values and developing or changing securities laws and other regulations. Investments in frontier market countries generally are less liquid and subject to greater price volatility than investments in developed markets or emerging markets.

Credit Risk. Investments in fixed income securities or other income instruments (referred to below as "debt instruments")  are subject to the risk of non-payment of scheduled principal and interest. Changes in economic conditions or other circumstances may reduce the capacity of the party obligated to make principal and interest payments on such instruments and may lead to defaults. Such non-payments and defaults may reduce the value of Fund shares and income distributions. The value of debt instruments also may decline because of concerns about the issuer's ability to make principal and interest payments. In addition, the credit ratings of debt instruments may be lowered if the financial condition of the party obligated to make payments with respect to such instruments deteriorates. In the event of bankruptcy of the issuer of a debt instrument, the Fund could experience delays or limitations with respect to its ability to realize the benefits of any collateral securing the instrument. In order to enforce its rights in the event of a default, bankruptcy or similar situation, the Fund may be required to retain legal or similar counsel, which may increase the Fund's operating expenses and adversely affect net asset value.

Interest Rate Risk. In general, the value of income securities will fluctuate based on changes in interest rates. The value of these securities is likely to increase when interest rates fall and decline when interest rates rise. Duration measures a fixed-income security's price sensitivity to changes in the general level of interest rates.  Generally, securities with longer durations or maturities are more sensitive to changes in interest rates than securities with shorter durations or maturities, causing them to be more volatile. Conversely, fixed-income securities with shorter durations or maturities will be less volatile but may provide lower returns than fixed-income securities with longer durations or maturities. In a rising interest rate environment, the duration of income securities that have the ability to be prepaid or called by the issuer may be extended. In a declining interest rate environment, the proceeds from prepaid or maturing instruments may have to be reinvested at a lower interest rate.

Currency Risk. Exchange rates for currencies fluctuate daily. The value of foreign investments may be affected favorably or unfavorably by changes in currency exchange rates in relation to the  U.S. dollar. Currency markets generally are not as regulated as securities markets and currency transactions are subject to settlement, custodial and other operational risks.

Pooled Investment Vehicles Risk. Pooled investment vehicles are open- and closed-end investment companies and exchange-traded funds ("ETFs"). Pooled investment vehicles are subject to the risks of investing in the underlying securities or other investments. Shares of closed-end investment companies and ETFs may trade at a premium or discount to net asset value and are subject to secondary market trading risks. In addition, the Fund will bear a pro rata portion of the operating expenses of a pooled investment vehicle in which it invests.

Focused Investment Risk. To the extent the Fund has substantial investments in a relatively small number of securities or issuers, or a particular market, industry, group of industries, country, region, group of countries, asset class or sector, the Fund's performance will be more susceptible to any single economic, market, political, or regulatory occurrence affecting those particular securities or issuers or that particular market, industry, group of industries, country, region, group of countries, assets class, or sector than a fund that invests more broadly.

Sector Risk. Because the Fund may, under certain circumstances, invest a significant portion of its assets in one or more sectors, the value of Fund shares may be affected by events that adversely affect such sector(s) and may fluctuate more than that of a fund that invests more broadly.

Derivatives Risk. The Fund's exposure to derivatives involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other investments. The use of derivatives can lead to losses because of adverse movements in the price or value of the security, instrument, index, currency, commodity, economic indicator or event underlying a derivative ("reference instrument"), due to failure of a counterparty or due to tax or regulatory constraints. Derivatives may create leverage in the Fund, which represents a non-cash exposure to the underlying reference instrument. Leverage can increase both the risk and return potential of the Fund. Derivatives risk may be more significant when derivatives are used to enhance return or as a substitute for a cash investment position, rather than solely to hedge the risk of a position held by the Fund. Use of derivatives involves the exercise of specialized skill and judgment, and a transaction may be unsuccessful in whole or in part because of market behavior or unexpected events. Changes in the value of a derivative (including one used for hedging) may not correlate perfectly with the underlying reference instrument. Derivative instruments traded in over-the-counter markets may be difficult to value, may be illiquid, and may be subject to wide swings in valuation caused by changes in the value of the underlying reference instrument. If a derivative's  counterparty is unable to honor its commitments, the value of Fund shares may decline and the Fund could experience delays in (or be unable to achieve) the return of collateral or other assets held by the counterparty. The loss on derivative transactions may substantially exceed the initial investment. A derivative investment also involves the risks relating to the reference instrument underlying the investment.

When-Issued and Forward Commitment Risk. Securities purchased on a when-issued or forward commitment basis are subject to the risk that when delivered they will be worth less than the agreed upon payment price.

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ETN Risk. ETNs are debt obligations and their payments of interest or principal are linked to the performance of a reference investment (typically an index). ETNs are subject to the performance of their issuer and may lose all or a portion of their entire value if the issuer fails or its credit rating changes. An ETN that is tied to a specific index may not be able to replicate and maintain exactly the composition and weighting of the components of that index. ETNs also incur certain expenses not incurred by the reference investment and the cost of owning an ETN may exceed the cost of investing directly in the reference investment. The market trading price of an ETN may be more volatile than the reference investment it is designed to track. The Fund may purchase an ETN at prices that exceed its net asset value and may sell such investments at prices below such net asset value. The Fund may not be able to liquidate ETN holdings at the time and price desired, which may impact Fund performance.

Smaller Company Risk. The stocks of smaller, less seasoned companies are generally subject to greater price fluctuations, limited liquidity, higher transaction costs and higher investment risk than the stocks of larger, more established companies. Such companies may have limited product lines, markets or financial resources, may be dependent on a limited management group, and may lack substantial capital reserves or an established performance record. There may be generally less publicly available information about such companies than for larger, more established companies. Stocks of these companies frequently have lower trading volumes making them more volatile and potentially less liquid and more difficult to value.

U.S. Government Securities Risk. Different types of U.S. government securities are subject to different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. Although certain U.S. Government-sponsored agencies (such as the Federal Home Loan Mortgage Corporation and the Federal National Mortgage Association) may be chartered or sponsored by acts of Congress, their securities are neither issued nor guaranteed by the U.S. Treasury. With respect to U.S. government securities that are not backed by the full faith and credit of the United States, there is a risk that the U.S. Government will not provide financial support to such U.S. government agencies, instrumentalities or sponsored enterprises if not obligated to do so by law. U.S. Treasury and U.S. Government agency securities generally have a lower return than other obligations because of their higher credit quality and market liquidity.

Lower Rated Investments Risk. Investments rated below investment grade and comparable unrated investments (sometimes referred to as "junk") are speculative because of increased credit risk relative to other fixed income investments. Changes in economic conditions or other circumstances typically have a greater effect on the ability of issuers of lower rated investments to make principal and interest payments than they do on issuers of higher rated investments. An economic downturn generally leads to a higher non-payment rate, and a lower rated investment may lose significant value before a default occurs. Lower rated investments typically are subject to greater price volatility and illiquidity than higher rated investments.

Municipal Obligations Risk. Because the Fund may invest in municipal obligations, the Fund may be susceptible to political, legislative, economic, regulatory, tax or other factors affecting issuers of these municipal obligations, such as state and local governments and their agencies. To the extent that the Fund invests in municipal obligations of issuers in the same state, U.S. territory, or economic sector, it could be more sensitive to economic, business or political developments that affect such state or sector. Municipal obligations and their issuers may be more susceptible to downgrade, loss of revenue, default and bankruptcy during periods of economic stress.  The amount of public information available about municipal obligations is generally less than for corporate equities or bonds, meaning that the investment performance of municipal obligations may be more dependent on the analytical abilities of the investment adviser than stock or corporate bond investments. The secondary market for municipal obligations also tends to be less well-developed and less liquid than many other securities markets, which may limit the Fund's ability to sell its municipal obligations at attractive prices. The differences between the price at which an obligation can be purchased and the price at which it can be sold may widen during periods of market distress. Less liquid obligations can become more difficult to value and be subject to erratic price movements.  

Real Estate Risk. Real estate investments are subject to risks associated with owning real estate, including declines in real estate values, increases in property taxes, fluctuations in interest rates, limited availability of mortgage financing, decreases in revenues from underlying real estate assets, declines in occupancy rates, changes in government regulations affecting zoning, land use, and rents, environmental liabilities, and risks related to the management skill and creditworthiness of the issuer. Companies in the real estate industry may also be subject to liabilities under environmental and hazardous waste laws, among others. REITs  must satisfy specific requirements for favorable tax treatment and can involve unique risks in addition to the risks generally affecting the real estate industry. Changes in underlying real estate values may have an exaggerated effect to the extent that investments are concentrated in particular geographic regions or property types.

Commodity-Related Investments Risk. The value of commodity investments will generally be affected by overall market movements and factors specific to a particular industry or commodity, which may include weather, embargoes, tariffs, and health, political, international and regulatory developments. Economic and other events (whether real or perceived) can reduce the demand for commodities, which may reduce market prices and cause the value of the Fund's commodity investments to fall. The frequency

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and magnitude of such changes are unpredictable. Exposure to commodities and commodity markets may subject the Fund to greater volatility than investments in traditional securities. No active trading market may exist for certain commodity investments, which may impair the ability of the Fund to sell or to realize the full value of such investments in the event of the need to liquidate such investments. In addition, adverse market conditions may impair the liquidity of actively traded commodity investments.

Liquidity Risk. The Fund is exposed to liquidity risk when trading volume, lack of a market maker or trading partner, large position size, market conditions, or legal restrictions impair its ability to sell particular investments or to sell them at advantageous market prices. Consequently, the Fund may have to accept a lower price to sell an investment or continue to hold it or keep the position open, sell other investments to raise cash or abandon an investment opportunity, any of which could have a negative effect on the Fund's performance. These effects may be exacerbated during times of financial or political stress.

Additional Risks of Loans. Loans are traded in a private, unregulated inter-dealer or inter-bank resale market and are generally subject to contractual restrictions that must be satisfied before a loan can be bought or sold. These restrictions may impede the Fund's ability to buy or sell loans (thus affecting their liquidity) and may negatively impact the transaction price. See also "Market Risk" above. It also may take longer than seven days for transactions in loans to settle. Due to the possibility of an extended loan settlement process, the Fund may hold cash, sell investments or temporarily borrow from banks or other lenders to meet short-term liquidity needs, such as to satisfy redemption requests from Fund shareholders. The types of covenants included in loan agreements generally vary depending on market conditions, the  creditworthiness of the issuer, the nature of the collateral securing the loan and possibly other factors. Loans with fewer covenants that restrict activities of the borrower may provide the borrower with more flexibility to take actions that may be detrimental to the loan holders and provide fewer investor protections in the event of such actions or if covenants are breached. The Fund may experience relatively greater realized or unrealized losses or delays and expense in enforcing its rights with respect to loans with fewer restrictive covenants. Loans to entities located outside of the  U.S. (including loans to sovereign entities) may have substantially different lender protections and covenants as compared to loans to U.S. entities and may involve greater risks. The Fund may have difficulties and incur expense enforcing its rights with respect to non-U.S. loans and such loans could be subject to bankruptcy laws that are materially different than in the U.S. Sovereign entities may be unable or unwilling to meet their obligations under a loan due to budgetary limitations or economic or political changes within the country. Loans may be structured such that they are not securities under securities law, and in the event of fraud or misrepresentation by a borrower, lenders may not have the protection of the anti-fraud provisions of the federal securities laws. Loans are also subject to risks associated with other types of income investments, including credit risk and risks of lower rated investments.

Mortgage- and Asset-Backed Securities Risk. Mortgage- and asset-backed securities represent interests in "pools" of commercial or residential mortgages or other assets, including consumer loans or receivables. Movements in interest rates (both increases and decreases) may quickly and significantly reduce the value of certain types of mortgage- and asset-backed securities. Although certain mortgage- and asset-backed securities are guaranteed as to timely payment of interest and principal by a government entity, the market price for such securities is not guaranteed and will fluctuate. The purchase of mortgage- and asset-backed securities issued by non-government entities may entail greater risk than such securities that are issued or guaranteed by a government entity. Mortgage- and asset-backed securities issued by non-government entities may offer higher yields than those issued by government entities, but may also be subject to greater volatility than government issues and can also be subject to greater credit risk and the risk of default on the underlying mortgages or other assets. Investments in mortgage- and asset-backed securities are subject to both extension risk, where borrowers pay off their debt obligations more slowly in times of rising interest rates, and prepayment risk, where borrowers pay off their debt obligations sooner than expected in times of declining interest rates.

Leverage Risk. Certain Fund transactions may give rise to leverage. Leverage can result from a non-cash exposure to an underlying reference instrument. Leverage can increase both the risk and return potential of the Fund. The use of leverage may cause the Fund to maintain liquid assets or liquidate portfolio positions when it may not be advantageous to do so to satisfy its obligations. Leverage may cause the Fund's share price to be more volatile than if it had not been leveraged, as certain types of leverage may exaggerate the effect of any increase or decrease in the value of the Fund's portfolio securities. The Fund may not be able to adjust its use of leverage rapidly enough to respond to interest rate volatility, inflation, and other changing market conditions. As a result, the Fund's use of leverage may have a negative impact on the Fund's performance from time to time. The loss on leveraged investments may substantially exceed the initial investment.

Zero-Coupon Bond  Risk. Zero-coupon bonds  may experience greater volatility in market value due to changes in interest rates. The Fund accrues income on the discount amortization of these investments, which it is required to distribute each year. The Fund may be required to sell investments to obtain cash needed for income distributions.

Short Sale Risk. The Fund will incur a loss as a result of a short sale if the price of the security sold short increases in value between the date of the short sale and the date on which the Fund purchases the security to replace the borrowed security. Short sale risks include, among others, the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale may fail to honor its contract terms, causing a loss to the Fund.

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Risks Associated with Active and Quantitative Management. The success of the Fund's investment strategy depends on portfolio management's successful application of analytical skills and investment judgment. Active management involves subjective decisions and there is no guarantee that such decisions will produce the desired results or expected returns. The portfolio managers also use quantitative investment techniques and analyses in making investment decisions for the Fund. Funds that are actively managed, in whole or in part, according to quantitative investment techniques can perform differently from the market, based on the investment techniques and factors used in the model or analysis, the weight placed on each factor, and changes from the factors' historical trends. There is a risk that the construction and implementation of the quantitative techniques may not adequately take into account certain factors, may contain design flaws or inaccurate assumptions, or may rely on inaccurate data inputs, which may negatively impact performance. There can be no assurance that these techniques will achieve the desired results.

Securities Lending Risk. Securities lending involves the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund also may lose rights in the collateral if the borrower fails financially. The Fund could also lose money if the value of the collateral decreases or if the value of any investments made with cash collateral declines.

General Fund Investing Risks. The Fund is not a complete investment program and there is no guarantee that the Fund will achieve its investment objective. It is possible to lose money by investing in the Fund. The Fund is designed to be a long-term investment vehicle and is not suited for short-term trading. Investors in the Fund should have a long-term investment perspective and be able to tolerate potentially sharp declines in value. Purchase and redemption activities by Fund shareholders may impact the management of the Fund and its ability to achieve its investment objective(s). In addition, the redemption by one or more large shareholders or groups of shareholders of their holdings in the Fund could have an adverse impact on the remaining shareholders in the Fund. The Fund relies on various service providers, including the investment adviser and sub-adviser, if applicable, in its operations and is susceptible to operational, information security and related events (such as public health crises, cyber or hacking attacks) that may affect the service providers or the services that they provide to the Fund. An 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.

Performance

The following bar chart and table provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year and how the Fund's average annual returns over time compare with those of one or more indexes intended to measure broad market performance. The Fund's primary benchmark index was changed from Bloomberg U.S. Aggregate Bond Index to MSCI World Index effective August 18, 2025 as a result of changes to the Fund's Principal Investment Strategies. The additional indexes in the table provide a means to compare the Fund's average annual returns to a benchmark that the investment adviser believes is representative of the Fund's investment universe. The returns in the bar chart are for Class A shares and do not reflect a sales charge. If the sales charge was reflected, the returns would be lower. Past performance (both before and after taxes) is not necessarily an indication of how the Fund will perform in the future. The Fund's performance for certain periods reflects the effects of expense reductions. Absent these reductions, performance for certain periods would have been lower. In addition, prior to August 18, 2025, the Fund was sub-advised with a different portfolio management team under different Principal Investment Strategies. Performance would likely have been different if the Fund's current Principal Investment Strategies had been in effect during the periods prior to August 18, 2025. Updated Fund performance information can be obtained by visiting www.eatonvance.com.

During the period shown in the bar chart above:

The year-to-date total return through the end of the most recent calendar quarter (December 31, 2024 to September 30, 2025) was 9.45%.

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Average Annual Total Return (for the calendar periods ended December 31, 2024)

These returns reflect the maximum current sales charge for Class A (5.25%) and any applicable contingent deferred sales charge ("CDSC") for Class C. Effective November 5, 2020, Class C shares automatically convert to Class A shares eight years after purchase. The average annual total returns listed for Class C reflect conversion to Class A shares after eight years. Prior to November 5, 2020, Class C shares automatically converted to Class A shares ten years after purchase. The Fund commenced operations on September 30, 2011. Investors cannot invest directly in an Index.

Source for  MSCI World Index and MSCI ACWI Index: MSCI. MSCI data may not be reproduced or used for any other purpose.  MSCI provides no warranties, has not prepared or approved this report, and has no liability hereunder.  

BLOOMBERG^® is a trademark and service mark of Bloomberg Finance L.P. and its affiliates (collectively "Bloomberg"). BARCLAYS^® is a trademark and service mark of Barclays Bank Plc (collectively with its affiliates, "Barclays"), used under license. Bloomberg or Bloomberg's licensors, including Barclays, own all proprietary rights in the Bloomberg Barclays Indices. Neither Bloomberg nor Barclays is affiliated with Eaton Vance, and neither approves, endorses, reviews or recommends the Fund. Neither Bloomberg nor Barclays guarantees the timeliness, accurateness or completeness of any data or information relating to Bloomberg U.S. Aggregate Bond Index, and neither shall be liable in any way to Eaton Vance, investors in the Fund or other third parties in respect of the use or accuracy of Bloomberg U.S. Aggregate Bond Index  or any data included therein.  

After-tax returns are calculated using the highest historical individual U.S. federal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on a shareholder's tax situation and the actual characterization of distributions, and may differ from those shown. After-tax returns are not relevant to shareholders who hold shares in tax-deferred accounts or to shares held by non-taxable entities. After-tax returns for other Classes of shares will vary from the after-tax returns presented for Class A shares.  Return After Taxes on Distributions for a period may be the same as Return Before Taxes for that period because no taxable distributions were made during that period. Also, Return After Taxes on Distributions and Sale of Fund Shares for a period may be greater than or equal to Return Before Taxes and/or Return After Taxes on Distributions for the same period because of losses realized on the sale of Fund shares.

Management

Investment Adviser. Eaton Vance Management ("Eaton Vance").

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Portfolio Managers

Purchase and Sale of Fund Shares

You may purchase, redeem or exchange Fund shares on any business day, which is any day the New York Stock Exchange is open for business.  You may purchase, redeem or exchange Fund shares either through your financial intermediary or (except for purchases of Class C shares by accounts with no specified financial intermediary) directly from the Fund either by writing to the Fund, P.O. Box 534439, Pittsburgh, PA 15253-4439, or by calling 1-800-262-1122. The minimum initial purchase or exchange into the Fund is $1,000 for each Class (with the exception of Class I) and $1,000,000 for Class I (waived in certain circumstances). There is no minimum for subsequent investments.

Tax Information

If your shares are held in a taxable account, the Fund's distributions will be taxed to you as ordinary income and/or capital gains, unless you are exempt from taxation. If your shares are held in a tax-advantaged account, you will generally be taxed only upon withdrawals from the account.

Payments to Broker-Dealers and Other Financial Intermediaries

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