Form 485BPOS Vanguard Montgomery Fund

Fund Summary

Investment Objective

The Fund seeks to provide long-term capital appreciation while limiting exposure to general stock market risk.

Fees and Expenses

The following table describes the fees and expenses you may pay if you buy and hold Investor Shares of the Fund.

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Example

The following example is intended to help you compare the cost of investing in the Fund’s Investor Shares with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you invested $10,000 in the Fund’s shares. This example assumes that the Shares provide a return of 5% each year and that total annual fund operating expenses remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you redeem your investment at the end of the given 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” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in more taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the previous expense example, reduce the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 68% of the average value of its portfolio.

Principal Investment Strategies

The Fund follows a market neutral strategy, which the Fund defines as a strategy designed to produce a portfolio that is neutral with respect to general stock market risk (sometimes referred to as beta neutrality). Beta is a measure of a portfolio’s volatility relative to the volatility of the general stock market. The Fund, as a whole, does not seek to adhere to any other definition of market neutrality.

To implement the strategy, the advisor buys securities that it believes offer an appropriate balance between strong growth prospects and reasonable valuations relative to their industry peers and sells short securities that it considers to be overvalued, in amounts that it believes will achieve market neutrality. By taking long and short positions in different securities, the Fund attempts to limit the effect of market movements on portfolio performance. The advisor does this by using a quantitative process and may, at any time, buy or sell short any number of publicly traded, exchange-listed equity securities and may emphasize specific industries, styles (growth/value), capitalization ranges, countries, or other factors. The overall performance of the Fund depends on the net performance of its long and short positions, and it is possible for the Fund to experience a net loss across all positions. If the Fund’s investment strategy is successful, however, the net performance of its long

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and short positions will produce long-term capital appreciation that reflects the quality of the advisor’s security selections, with limited exposure to general stock market risk.

The Fund’s long/short market neutral investment strategy is an absolute-return investment approach seeking performance that exceeds the returns of 3-month U.S. Treasury bills. An investment in the Fund, however, is different from an investment in 3-month U.S. Treasury bills because, among other things, U.S. Treasury bills are backed by the full faith and credit of the U.S. government, U.S. Treasury bills have a fixed rate of return, investors in U.S. Treasury bills have a very low risk of losing their investment, and an investment in the Fund is expected to be substantially more volatile than an investment in U.S. Treasury bills.

Because of the Fund’s market neutral strategy, the Fund’s overall price movements are not expected to correlate with the general stock market’s price movements. In other words, the Fund is expected to have returns that are independent of the returns and direction of the general stock market.

Principal Risks

An investment in the Fund could lose money over short or even long periods, and the entire amount invested could be lost. There can be no assurance that the Fund’s investment objective or strategies will be achieved, and results may vary substantially over time. The Fund is subject to the following risks, which could affect the Fund’s performance:

• Strategy risk, which is the chance that the Fund’s investment strategy will not succeed. There is no guarantee that the Fund will be able to limit exposure to general stock market risk or produce returns that exceed the returns of 3-month U.S. Treasury bills. The Fund’s use of short sales in combination with its long positions in an attempt to improve performance or to reduce overall portfolio risk may not be successful and may result in greater losses or lower positive returns than if the Fund held only long positions. When the general stock market is performing strongly, the Fund is expected to underperform the market because the Fund’s short positions will likely lose money. If the Fund’s market neutral strategy is unsuccessful, the Fund may be subject to stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices.

• Short-selling risk, which is the chance that the Fund will lose money in connection with its short sales of securities. Short selling allows an investor to profit from declines in the prices of securities. To engage in a short sale, the Fund must “borrow” securities for a fee. To close out short positions, the Fund may have to sell related long positions at disadvantageous times to produce cash to unwind a short position. There is no guarantee that the price of the borrowed securities will decline; in fact, it may rise. The Fund’s loss on a short sale is theoretically unlimited, because there is no upward limit on the price a borrowed security could attain. Short selling involves

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higher transaction costs than long-only investing, which could offset any gains and increase any losses.

• Manager risk, which is the chance that poor security selection or strategy execution will cause the Fund to fail to achieve its investment objective or to underperform other funds with a similar investment strategy. The advisor’s security selection process may not eliminate all stock market risk factors associated with the long and short positions it establishes for the Fund. It is possible that the stocks the Fund holds long will decline in value at the same time that the stocks it holds short increase in value, thereby increasing potential losses to the Fund. Any gain from a short position may be partially or totally offset by a decline in a long position, or vice versa.

• Investment risk, which is the chance that the Fund’s advisor will take positions in securities, intentionally or unintentionally, that increase the Fund’s sensitivity to certain investment factors. These factors may include, but are not limited to, market capitalization ranges, styles (growth/value), and industries of the underlying securities. These factors may cause the Fund to fail to achieve its investment objective of limiting exposure to general stock market risk or cause it to underperform other funds with a similar investment strategy.

• Derivatives risk. The Fund may invest in derivatives, which may involve risks different from, and possibly greater than, those of investments directly in the underlying securities or assets.

An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Annual Total Returns

The following bar chart and table are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund‘s Investor Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Investor Shares compare with those of a relevant market index and a comparative benchmark, which have investment characteristics similar to those of the Fund. Returns for the Equity Market Neutral Funds Average are derived from data provided by Lipper, a Thomson Reuters Company. Keep in mind that the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future. Updated performance information is available on our website at vanguard.com/performance or by calling Vanguard toll-free at 800-662-7447.

The performance figures in this section for the periods prior to November 30, 2007, are those of the Fund’s predecessor fund, Laudus Rosenberg U.S. Large/Mid Capitalization Long/Short Equity Fund (Laudus Fund). The Laudus Fund was sponsored and managed by Charles Schwab Investment Management, Inc., and sub-advised by AXA Rosenberg Investment Management LLC (AXA Rosenberg). The Laudus Fund was reorganized

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with and into Vanguard Market Neutral Fund on November 30, 2007. The Fund continues to operate as a market neutral fund and maintains a substantially similar investment objective and substantially similar principal investment strategies to those of the Laudus Fund, except that, effective July 25, 2008, the Fund revised its investment strategies to focus on beta neutrality and to enable the Fund to invest to a greater extent in foreign securities. In addition, effective April 30, 2010, the Fund’s investment advisory team was restructured, which was also reflected in its investment strategies.

Annual Total Returns — Vanguard Market Neutral Fund Investor Shares

During the periods shown in the bar chart, the highest return for a calendar quarter was 8.79% (quarter ended December 31, 2007), and the lowest return for a quarter was –6.54% (quarter ended March 31, 2009).

Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. When after-tax returns are calculated, it is assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local

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income taxes are not reflected in the calculations. Please note that after-tax returns are not relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. Also, figures captioned Return After Taxes on Distributions and Sale of Fund Shares may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.

Investment Advisor

The Vanguard Group, Inc. (Vanguard)

Portfolio Managers

James P. Stetler, Principal of Vanguard. He has co-managed the Fund since 2012.

Michael R. Roach, CFA, Portfolio Manager at Vanguard. He has co-managed the Fund since 2012.

Binbin Guo, Ph.D., Principal of Vanguard and head of Equity Research and Portfolio Strategies of Vanguard’s Quantitative Equity Group. He has co-managed the Fund since 2016.

Purchase and Sale of Fund Shares

You may purchase or redeem shares online through our website (vanguard.com), by mail (The Vanguard Group, P.O. Box 1110, Valley Forge, PA 19482-1110), or by telephone (800-662-2739). The minimum investment amount required to open and maintain a Fund account for Investor Shares is $250,000. The minimum investment amount required to add to an existing Fund account is generally $1. Institutional and financial intermediary clients should contact Vanguard for information on special eligibility rules that may apply to them regarding Investor Shares.

Tax Information

The Fund’s distributions may be taxable as ordinary income or capital gain. If you are investing through a tax-deferred retirement account, such as an IRA, special tax rules apply.

Payments to Financial Intermediaries

The Fund and its investment advisor do not pay financial intermediaries for sales of Fund shares.

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More on the Fund

This prospectus describes the principal risks you would face as a Fund shareholder. It is important to keep in mind one of the main axioms of investing: generally, the higher the risk of losing money, the higher the potential reward. The reverse, also, is generally true: the lower the risk, the lower the potential reward. As you consider an investment in any mutual fund, you should take into account your personal tolerance for fluctuations in the securities markets. Look for this symbol throughout the prospectus. It is used to mark detailed information about the more significant risks that you would confront as a Fund shareholder. To highlight terms and concepts important to mutual fund investors, we have provided Plain Talk^® explanations along the way. Reading the prospectus will help you decide whether the Fund is the right investment for you. We suggest that you keep this prospectus for future reference.

Share Class Overview

This prospectus offers the Fund’s Investor Shares. A separate prospectus offers the Fund’s Institutional Shares, which are generally for investors who invest a minimum of $5 million.

Both share classes offered by the Fund have the same investment objective, strategies, and policies. However, different share classes have different expenses; as a result, their investment performances will differ.

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The following sections explain the principal investment strategies and policies that the Fund uses in pursuit of its objective. The Fund‘s board of trustees, which oversees the Fund’s management, may change investment strategies or policies in the interest of shareholders without a shareholder vote, unless those strategies or policies are designated as fundamental. Note that the Fund’s investment objective is not fundamental and may be changed without a shareholder vote.

An investment in the Fund could lose money over short or even long periods, and the entire amount invested could be lost. There can be no assurance that the Fund’s investment objective or strategies will be achieved, and results may vary substantially over time.

Security Selection

The Vanguard Group, Inc. (Vanguard), the Fund’s investment advisor, selects and maintains a diversified portfolio of common stocks for the Fund. The advisor employs active investment management methods, which means that securities are bought and sold according to the advisor’s evaluations of companies and their financial prospects, the prices of the securities, and the stock market and the economy in general.

The Fund follows a market neutral strategy, which the Fund defines as a strategy designed to produce a portfolio that is neutral with respect to general stock market risk (sometimes referred to as beta neutrality). Beta is a measure of a portfolio’s volatility relative to the volatility of the general stock market. The Fund, as a whole, does not seek to adhere to any other definition of market neutrality. By taking long and short positions in different securities, the Fund attempts to limit the effect of market movements on portfolio performance. The advisor may, at any time, buy or sell short any number of publicly traded, exchange-listed equity securities and may emphasize specific industries, styles (growth/value), capitalization ranges, countries, or other factors. The overall performance of the Fund depends on the net performance of its long and short positions, and it is possible for the Fund to experience a net loss across all positions. If the Fund’s investment strategy is successful, however, the net performance of its long and short positions will produce long-term capital appreciation that reflects the quality of the advisor’s security selections, with limited exposure to general stock market risk.

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To implement the strategy, Vanguard buys securities that it believes offer an appropriate balance between strong growth prospects and reasonable valuations relative to their industry peers and sells short securities that it considers to be overvalued, in amounts that it believes will achieve market neutrality. Vanguard manages the portfolio through the use of a quantitative process that was developed by a team of Vanguard researchers. This process is continually evolving. All potential enhancements to the process go through rigorous peer vetting and validation before being implemented. A team of portfolio managers utilizes the resulting process to determine which securities to buy long and sell short in the portfolio.

The Fund is subject to strategy risk, which is the chance that the Fund’s investment strategy will not succeed. There is no guarantee that the Fund will be able to limit exposure to general stock market risk or produce returns that exceed the returns of 3-month U.S. Treasury bills. The Fund’s use of short sales in combination with its long positions in an attempt to improve performance or to reduce overall portfolio risk may not be successful and may result in greater losses or lower positive returns than if the Fund held only long positions. When the general stock market is performing strongly, the Fund is expected to underperform the market because the Fund’s short positions will likely lose money. If the Fund’s market neutral strategy is unsuccessful, the Fund may be subject to stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices.

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The Fund is subject to short-selling risk, which is the chance that the Fund will lose money in connection with its short sales of securities. Short selling allows an investor to profit from declines in the prices of securities. To engage in a short sale, the Fund must “borrow” securities for a fee. To close out short positions, the Fund may have to sell related long positions at disadvantageous times to produce cash to unwind a short position. There is no guarantee that the price of the borrowed securities will decline; in fact, it may rise. The Fund’s loss on a short sale is theoretically unlimited, because there is no upward limit on the price a borrowed security could attain. Short selling involves higher transaction costs than long-only investing, which could offset any gains and increase any losses.

The market value of the long and short positions in the Fund will not always be equal because of continuous changes in the prices of securities. The Fund expects that the advisor will need to frequently rebalance its long and short positions. The Fund’s holdings will also need to reflect changes in the universe of securities the advisor considers undervalued or overvalued. As a result, the Fund is expected to experience a high portfolio turnover rate, possibly in excess of 100%.

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The Fund is subject to manager risk, which is the chance that poor security selection or strategy execution will cause the Fund to fail to achieve its investment objective or to underperform other funds with a similar investment strategy. The advisor’s security selection process may not eliminate all stock market risk factors associated with the long and short positions it establishes for the Fund. It is possible that the stocks the Fund holds long will decline in value at the same time that the stocks it holds short increase in value, thereby increasing potential losses to the Fund. Any gain from a short position may be partially or totally offset by a decline in a long position, or vice versa.

The Fund is subject to investment risk, which is the chance that the Fund’s advisor will take positions in securities, intentionally or unintentionally, that increase the Fund’s sensitivity to certain investment factors. These factors may include, but are not limited to, market capitalization ranges, styles (growth/ value), and industries of the underlying securities. These factors may cause the Fund to fail to achieve its investment objective of limiting exposure to general stock market risk or cause it to underperform other funds with a similar investment strategy.

Other Investment Policies and Risks

In addition to investing in publicly traded stocks on a long and short basis, the Fund may make other kinds of investments to achieve its objective.

The Fund may invest in derivatives. In general, investments in derivatives may involve risks different from, and possibly greater than, those of investments directly in the underlying securities or assets.

Generally speaking, a derivative is a financial contract whose value is based on the value of a financial asset (such as a stock, a bond, or a currency), a physical asset (such as gold, oil, or wheat), a market index (such as the S&P 500 Index), or a reference rate (such as LIBOR). The Fund may invest in derivatives only if the expected risks and rewards of the derivatives are consistent with the investment objective, policies, strategies, and risks of the Fund as disclosed in this prospectus. In particular, derivatives will be used only when they may help the advisor:

• Invest in eligible asset classes with greater efficiency and lower cost than is possible through direct investment.

• Add value when these instruments are attractively priced.

The market for many derivatives is, or suddenly can become, illiquid, which may result in significant, rapid, and unpredictable changes in the prices for derivatives. The Fund’s use of a derivative subjects it to the risk of nonperformance by the counterparty,

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potentially resulting in delayed, partial, or even nonpayment of amounts due under the derivative contract.

The Fund‘s derivative investments may include futures contracts and options thereon, options on stocks or stock indexes, warrants, swap agreements, or other derivatives. Losses (or gains) involving futures contracts can sometimes be substantial—in part because a relatively small price movement in a futures contract may result in an immediate and substantial loss (or gain) for a fund. Similar risks exist for other types of derivatives.

Cash Management

The Fund‘s daily cash balance may be invested in one or more Vanguard CMT Funds, which are very low-cost money market funds. When investing in a Vanguard CMT Fund, the Fund bears its proportionate share of the at-cost expenses of the CMT Fund in which it invests. Vanguard receives no additional revenue from Fund assets invested in a Vanguard CMT Fund.

Temporary Investment Measures

The Fund may temporarily depart from its normal investment policies and strategies when the advisor believes that doing so is in the Fund‘s best interest, so long as the alternative is consistent with the Fund‘s investment objective. For instance, the Fund may invest beyond its normal limits in derivatives or exchange-traded funds that are consistent with the Fund‘s objective when those instruments are more favorably priced or provide needed liquidity, as might be the case if the Fund is transitioning assets from one advisor to another or receives large cash flows that it cannot prudently invest immediately.

In addition, the Fund may take temporary defensive positions that are inconsistent with its normal investment policies and strategies—for instance, by allocating substantial assets to cash equivalent investments or other less volatile instruments—in response to adverse or unusual market, economic, political, or other conditions. In

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doing so, the Fund may succeed in avoiding losses but may otherwise fail to achieve its investment objective.

Frequent Trading or Market-Timing

Background. Some investors try to profit from strategies involving frequent trading of mutual fund shares, such as market-timing. For funds holding foreign securities, investors may try to take advantage of an anticipated difference between the price of the fund’s shares and price movements in overseas markets, a practice also known as time-zone arbitrage. Investors also may try to engage in frequent trading of funds holding investments such as small-cap stocks and high-yield bonds. As money is shifted into and out of a fund by a shareholder engaging in frequent trading, the fund incurs costs for buying and selling securities, resulting in increased brokerage and administrative costs. These costs are borne by all fund shareholders, including the long-term investors who do not generate the costs. In addition, frequent trading may interfere with an advisor’s ability to efficiently manage the fund.

Policies to address frequent trading. The Vanguard funds (other than money market funds and short-term bond funds, but including Vanguard Short-Term Inflation-Protected Securities Index Fund) do not knowingly accommodate frequent trading. The board of trustees of each Vanguard fund (other than money market funds and short-term bond funds, but including Vanguard Short-Term Inflation-Protected Securities Index Fund) has adopted policies and procedures reasonably designed to detect and discourage frequent trading and, in some cases, to compensate the fund for the costs associated with it. These policies and procedures do not apply to Vanguard ETF^® Shares because frequent trading in ETF Shares generally does not disrupt portfolio management or otherwise harm fund shareholders. Although there is no assurance that Vanguard will be able to detect or prevent frequent trading or market-timing in all circumstances, the following policies have been adopted to address these issues:

• Each Vanguard fund reserves the right to reject any purchase request—including exchanges from other Vanguard funds—without notice and regardless of size. For example, a purchase request could be rejected because the investor has a history of frequent trading or if Vanguard determines that such purchase may negatively affect a fund’s operation or performance.

• Each Vanguard fund (other than money market funds and short-term bond funds, but including Vanguard Short-Term Inflation-Protected Securities Index Fund) generally prohibits, except as otherwise noted in the Investing With Vanguard section, an investor’s purchases or exchanges into a fund account for 30 calendar days (60 calendar days for participants in employer-sponsored defined contribution plans recordkept directly by Vanguard) after the investor has redeemed or exchanged out of that fund account.

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• Certain Vanguard funds charge shareholders purchase and/or redemption fees on transactions.

See the Investing With Vanguard section of this prospectus for further details on Vanguard’s transaction policies.

Each Vanguard fund (other than money market funds), in determining its net asset value, will use fair-value pricing when appropriate, as described in the Share Price section. Fair-value pricing may reduce or eliminate the profitability of certain frequent-trading strategies.

Do not invest with Vanguard if you are a market-timer.

Turnover Rate

Although the Fund generally seeks to invest for the long term, it may sell securities regardless of how long they have been held. The Financial Highlights section of this prospectus shows historical turnover rates for the Fund. A turnover rate of 100%, for example, would mean that the Fund had sold and replaced securities valued at 100% of its net assets within a one-year period. The average turnover rate for market neutral funds was approximately 289%, as reported by Morningstar, Inc., on December 31, 2015.

The Fund and Vanguard

The Fund is a member of The Vanguard Group, a family of more than 190 mutual funds holding assets of approximately $3 trillion. All of the funds that are members of The Vanguard Group (other than funds of funds) share in the expenses associated with administrative services and business operations, such as personnel, office space, and equipment.

Vanguard Marketing Corporation provides marketing services to the funds. Although shareholders do not pay sales commissions or 12b-1 distribution fees, each fund (other than a fund of funds) or each share class of a fund (in the case of a fund with multiple share classes) pays its allocated share of the Vanguard funds’ marketing costs.

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Investment Advisor

The Vanguard Group, Inc., P.O. Box 2600, Valley Forge, PA 19482, which began operations in 1975, serves as advisor to the Fund through its Quantitative Equity Group. As of December 31, 2015, Vanguard served as advisor for approximately $2.6 trillion in assets. Vanguard provides investment advisory services to the Fund on an at-cost basis, subject to the supervision and oversight of the trustees and officers of the Fund.

For the fiscal year ended December 31, 2015, the advisory expenses represented an effective annual rate of 0.08% of the Fund’s average net assets.

Although the Fund is managed solely by Vanguard, the Fund reserves the right to utilize a multimanager approach in the future. Under the terms of an SEC exemption, the Fund’s board of trustees may, without prior approval from shareholders, change the terms of an advisory agreement or hire a new investment advisor—either as a replacement for an existing advisor or as an additional advisor. Any significant change in the Fund’s advisory arrangements will be communicated to shareholders in writing. As the Fund’s sponsor and overall manager, Vanguard may provide additional investment advisory services to the Fund, on an at-cost basis, at any time. Vanguard may also recommend to the board of trustees that an advisor be hired, terminated, or replaced or that the terms of an existing advisory agreement be revised.

For a discussion of why the board of trustees approved the Fund’s investment advisory arrangement, see the most recent semiannual report to shareholders covering the fiscal period ended June 30.

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The managers primarily responsible for the day-to-day management of the Fund are:

James P. Stetler, Principal of Vanguard. He has been with Vanguard since 1982, has worked in investment management since 1996, has managed investment portfolios since 2003, and has co-managed the Fund since 2012. Education: B.S., Susquehanna University; M.B.A., Saint Joseph’s University.

Michael R. Roach, CFA, Portfolio Manager at Vanguard. He has been with Vanguard since 1998, has worked in investment management since 2001, and has co-managed the Fund since 2012. Education: B.S., Bloomsburg University; M.S., Drexel University.

Binbin Guo, Ph.D., Principal of Vanguard and head of Equity Research and Portfolio Strategies of Vanguard’s Quantitative Equity Group. He has oversight responsibility for the quantitative research team and develops portfolio strategies for equity and alternative asset classes. He has been with Vanguard since 2007 and has co-managed the Fund since 2016. Education: B.S. and M.S., Tsinghua University, China; Ph.D. and M.Phil., Yale University.

The Statement of Additional Information provides information about each portfolio manager’s compensation, other accounts under management, and ownership of shares of the Fund.

Dividends, Capital Gains, and Taxes

Fund Distributions

The Fund distributes to shareholders virtually all of its net income (interest and dividends, less expenses) as well as any net short-term or long-term capital gains realized from the sale of its holdings. Income and capital gains distributions, if any, generally occur annually in December. In addition, the Fund may occasionally make a supplemental distribution at some other time during the year. You can receive distributions of income or capital gains in cash, or you can have them automatically reinvested in more shares of the Fund.

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Basic Tax Points

Vanguard will send you a statement each year showing the tax status of all of your distributions. In addition, investors in taxable accounts should be aware of the following basic federal income tax points:

• Distributions are taxable to you whether or not you reinvest these amounts in additional Fund shares.

• Distributions declared in December—if paid to you by the end of January—are taxable as if received in December.

• Any dividend distribution or short-term capital gains distribution that you receive is taxable to you as ordinary income. If you are an individual and meet certain holding-period requirements with respect to your Fund shares, you may be eligible for reduced tax rates on “qualified dividend income,” if any, distributed by the Fund.

• Any distribution of net long-term capital gains is taxable to you as long-term capital gains, no matter how long you have owned shares in the Fund.

• Capital gains distributions may vary considerably from year to year as a result of the Fund‘s normal investment activities and cash flows.

• A sale or exchange of Fund shares is a taxable event. This means that you may have a capital gain to report as income, or a capital loss to report as a deduction, when you complete your tax return.

• Any conversion between classes of shares of the same fund is a nontaxable event. By contrast, an exchange between classes of shares of different funds is a taxable event.

Individuals, trusts, and estates whose income exceeds certain threshold amounts are subject to a 3.8% Medicare contribution tax on “net investment income.” Net investment income takes into account distributions paid by the Fund and capital gains from any sale or exchange of Fund shares.

Dividend distributions and capital gains distributions that you receive, as well as your gains or losses from any sale or exchange of Fund shares, may be subject to state and local income taxes.

The Fund’s short sales will be subject to tax rules that may affect the amount, timing, and character of distributions to shareholders. This prospectus provides general tax information only. If you are investing through a tax-deferred retirement account, such as an IRA, special tax rules apply. Please consult your tax advisor for detailed information about any tax consequences for you, including potential consequences for you if the Fund simultaneously holds long and short positions with respect to the same security.

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General Information

Backup withholding. By law, Vanguard must withhold 28% of any taxable distributions or redemptions from your account if you do not:

• Provide us with your correct taxpayer identification number.

• Certify that the taxpayer identification number is correct.

• Confirm that you are not subject to backup withholding.

Similarly, Vanguard must withhold taxes from your account if the IRS instructs us to do so.

Foreign investors. Vanguard funds offered for sale in the United States (Vanguard U.S. funds), including the Fund offered in this prospectus, are not widely available outside the United States. Non-U.S. investors should be aware that U.S. withholding and estate taxes and certain U.S. tax reporting requirements may apply to any investments in Vanguard U.S. funds. Foreign investors should visit the Non-U.S. Investors page on our website at vanguard.com for information on Vanguard’s non-U.S. products.

Invalid addresses. If a dividend distribution or capital gains distribution check mailed to your address of record is returned as undeliverable, Vanguard will automatically reinvest the distribution and all future distributions until you provide us with a valid mailing address. Reinvestments will receive the net asset value calculated on the date of the reinvestment.

Share Price

Share price, also known as net asset value (NAV), is calculated each business day as of the close of regular trading on the New York Stock Exchange (NYSE), generally 4 p.m., Eastern time. Each share class has its own NAV, which is computed by dividing the total assets, minus liabilities, allocated to the share class by the number of Fund shares outstanding for that class. On U.S. holidays or other days when the NYSE is

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closed, the NAV is not calculated, and the Fund does not sell or redeem shares. However, on those days the value of the Fund’s assets may be affected to the extent that the Fund holds securities that change in value on those days (such as foreign securities that trade on foreign markets that are open).

Stocks held by a Vanguard fund are valued at their market value when reliable market quotations are readily available from the principal exchange or market on which they are traded. Such securities are generally valued at their official closing price, the last reported sales price, or if there were no sales that day, the mean between the closing bid and asking prices. Certain short-term debt instruments used to manage a fund’s cash may be valued at amortized cost when it approximates fair value. The values of any foreign securities held by a fund are converted into U.S. dollars using an exchange rate obtained from an independent third party as of the close of regular trading on the NYSE. The values of any mutual fund shares held by a fund are based on the NAVs of the shares. The values of any ETF or closed-end fund shares held by a fund are based on the market value of the shares.

When a fund determines that market quotations either are not readily available or do not accurately reflect the value of a security, the security is priced at its fair value (the amount that the owner might reasonably expect to receive upon the current sale of the security). A fund also will use fair-value pricing if the value of a security it holds has been materially affected by events occurring before the fund’s pricing time but after the close of the principal exchange or market on which the security is traded. This most commonly occurs with foreign securities, which may trade on foreign exchanges that close many hours before the fund’s pricing time. Intervening events might be company-specific (e.g., earnings report, merger announcement) or country-specific or regional/global (e.g., natural disaster, economic or political news, act of terrorism, interest rate change). Intervening events include price movements in U.S. markets that exceed a specified threshold or that are otherwise deemed to affect the value of foreign securities. Fair-value pricing may be used for domestic securities—for example, if (1) trading in a security is halted and does not resume before the fund’s pricing time or a security does not trade in the course of a day and (2) the fund holds enough of the security that its price could affect the NAV.

Fair-value prices are determined by Vanguard according to procedures adopted by the board of trustees. When fair-value pricing is employed, the prices of securities used by a fund to calculate the NAV may differ from quoted or published prices for the same securities.

Vanguard fund share prices are published daily on our website at vanguard.com/prices.

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Financial Highlights

The following financial highlights table is intended to help you understand the Investor Shares‘ financial performance for the periods shown, and certain information reflects financial results for a single Investor Share. The total returns in the table represent the rate that an investor would have earned or lost each period on an investment in the Investor Shares (assuming reinvestment of all distributions). This information has been obtained from the financial statements audited by PricewaterhouseCoopers LLP, an independent registered public accounting firm, whose report—along with the Fund’s financial statements—is included in the Fund’s most recent annual report to shareholders. You may obtain a free copy of the latest annual or semiannual report by visiting vanguard.com or by contacting Vanguard by telephone or mail.

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Investing With Vanguard

This section of the prospectus explains the basics of doing business with Vanguard. Vanguard fund shares can be held directly with Vanguard or indirectly through an intermediary, such as a bank, a broker, or an investment advisor. If you hold Vanguard fund shares directly with Vanguard, you should carefully read each topic within this section that pertains to your relationship with Vanguard. If you hold Vanguard fund shares indirectly through an intermediary (including shares held through a Vanguard brokerage account), please see Investing With Vanguard Through Other Firms, and also refer to your account agreement with the intermediary for information about transacting in that account. Vanguard reserves the right to change the following policies without notice. Please call or check online for current information. See

Contacting Vanguard.

For Vanguard fund shares held directly with Vanguard, each fund you hold in an account is a separate “fund account.” For example, if you hold three funds in a nonretirement account titled in your own name, two funds in a nonretirement account titled jointly with your spouse, and one fund in an individual retirement account, you have six fund accounts—and this is true even if you hold the same fund in multiple accounts. Note that each reference to “you” in this prospectus applies to any one or more registered account owners or persons authorized to transact on your account.

Purchasing Shares

Vanguard reserves the right, without notice, to increase or decrease the minimum amount required to open, convert shares to, or maintain a fund account or to add to an existing fund account.

Investment minimums may differ for certain categories of investors.

Account Minimums for Investor Shares

To open and maintain an account. $250,000. Institutional and financial intermediary clients should contact Vanguard for information on special eligibility rules that may apply to them.

To add to an existing account. Generally $1.

How to Initiate a Purchase Request

Be sure to check Exchanging Shares, Frequent-Trading Limitations, and Other Rules You Should Know before placing your purchase request.

Online. You may open certain types of accounts, request a purchase of shares, and request an exchange through our website or our mobile application if you are registered for online access.

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By telephone. You may call Vanguard to begin the account registration process or request that the account-opening forms be sent to you. You may also call Vanguard to request a purchase of shares in your account or to request an exchange. See

Contacting Vanguard.

By mail. You may send Vanguard your account registration form and check to open a new fund account. To add to an existing fund account, you may send your check with an Invest-by-Mail form (from a transaction confirmation or your account statement), with a deposit slip (available online), or with a written request. You may also send a written request to Vanguard to make an exchange. For a list of Vanguard addresses, see Contacting Vanguard.

How to Pay for a Purchase

By electronic bank transfer. You may purchase shares of a Vanguard fund through an electronic transfer of money from a bank account. To establish the electronic bank transfer service on an account, you must designate the bank account online, complete a special form, or fill out the appropriate section of your account registration form. After the service is set up on your account, you can purchase shares by electronic bank transfer on a regular schedule (Automatic Investment Plan) or upon request. Your purchase request can be initiated online (if you are registered for online access), by telephone, or by mail.

By wire. Wiring instructions vary for different types of purchases. Please call Vanguard for instructions and policies on purchasing shares by wire. See Contacting Vanguard.

By check. You may make initial or additional purchases to your fund account by sending a check or by utilizing our mobile application if you are registered for online access. Also see How to Initiate a Purchase Request. Make your check payable to Vanguard and include the appropriate fund number (Vanguard—634).

By exchange. You may purchase shares of a Vanguard fund using the proceeds from the simultaneous redemption of shares of another Vanguard fund. You may initiate an exchange online (if you are registered for online access), by telephone, or by mail. See

Exchanging Shares.

Trade Date

The trade date for any purchase request received in good order will depend on the day and time Vanguard receives your request, the manner in which you are paying, and the type of fund you are purchasing. Your purchase will be executed using the net asset value (NAV) as calculated on the trade date. NAVs are calculated only on days that the New York Stock Exchange (NYSE) is open for trading (a business day).

For purchases by check into all funds other than money market funds and for purchases by exchange, wire, or electronic bank transfer (not using an Automatic

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Investment Plan) into all funds: If the purchase request is received by Vanguard on a business day before the close of regular trading on the NYSE (generally 4 p.m., Eastern time), the trade date for the purchase will be the same day. If the purchase request is received on a business day after the close of regular trading on the NYSE, or on a nonbusiness day, the trade date for the purchase will be the next business day.

For purchases by check into money market funds: If the purchase request is received by Vanguard on a business day before the close of regular trading on the NYSE (generally 4 p.m., Eastern time), the trade date for the purchase will be the next business day. If the purchase request is received on a business day after the close of regular trading on the NYSE, or on a nonbusiness day, the trade date for the purchase will be the second business day following the day Vanguard receives the purchase request. Because money market instruments must be purchased with federal funds and it takes a money market mutual fund one business day to convert check proceeds into federal funds, the trade date for the purchase will be one business day later than for other funds.

For purchases by electronic bank transfer using an Automatic Investment Plan: Your trade date generally will be the date you selected for withdrawal of funds from your designated bank account. Your bank account generally will be debited on the business day after your trade date. If the date you selected for withdrawal of funds from your bank account falls on a weekend, holiday, or other nonbusiness day, your trade date generally will be the previous business day. For retirement accounts, if the date you selected for withdrawal of funds from your designated bank account falls on the last business day of the year, your trade date will be the first business day of the following year. Please note that if you select the first of the month for automated withdrawals from your designated bank account, trades designated for January 1 will receive the next business day’s trade date.

If your purchase request is not accurate and complete, it may be rejected. See Other Rules You Should Know—Good Order.

For further information about purchase transactions, consult our website at vanguard.com or see Contacting Vanguard.

Other Purchase Rules You Should Know

Check purchases. All purchase checks must be written in U.S. dollars and must be drawn on a U.S. bank. Vanguard does not accept cash, traveler’s checks, or money orders. In addition, Vanguard may refuse “starter checks” and checks that are not made payable to Vanguard.

New accounts. We are required by law to obtain from you certain personal information that we will use to verify your identity. If you do not provide the information, we may not be able to open your account. If we are unable to verify your identity, Vanguard

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reserves the right, without notice, to close your account or take such other steps as we deem reasonable. Certain types of accounts may require additional documentation.

Refused or rejected purchase requests. Vanguard reserves the right to stop selling fund shares or to reject any purchase request at any time and without notice, including, but not limited to, purchases requested by exchange from another Vanguard fund. This also includes the right to reject any purchase request because the investor has a history of frequent trading or because the purchase may negatively affect a fund’s operation or performance.

Large purchases. Call Vanguard before attempting to invest a large dollar amount.

No cancellations. Vanguard will not accept your request to cancel any purchase request once processing has begun. Please be careful when placing a purchase request.

Converting Shares

When a conversion occurs, you receive shares of one class in place of shares of another class of the same fund. At the time of conversion, the dollar value of the “new” shares you receive equals the dollar value of the “old” shares that were converted. In other words, the conversion has no effect on the value of your investment in the fund at the time of the conversion. However, the number of shares you own after the conversion may be greater than or less than the number of shares you owned before the conversion, depending on the NAVs of the two share classes.

Vanguard will not accept your request to cancel any self-directed conversion request once processing has begun. Please be careful when placing a conversion request.

A conversion between share classes of the same fund is a nontaxable event.

Trade Date

The trade date for any conversion request received in good order will depend on the day and time Vanguard receives your request. Your conversion will be executed using the NAVs of the different share classes on the trade date. NAVs are calculated only on days that the NYSE is open for trading (a business day).

For a conversion request received by Vanguard on a business day before the close of regular trading on the NYSE (generally 4 p.m., Eastern time), the trade date will be the same day. For a conversion request received on a business day after the close of regular trading on the NYSE, or on a nonbusiness day, the trade date will be the next business day. See Other Rules You Should Know.

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Conversions to Institutional Shares

You are eligible for a self-directed conversion from Investor Shares to Institutional Shares of the Fund, provided that your account meets all Institutional Shares’ eligibility requirements. You may request a conversion through our website (if you are registered for online access), or you may contact Vanguard by telephone or by mail to request this transaction. Accounts that qualify for Institutional Shares will not be automatically converted.

Mandatory Conversions to Investor Shares

If an account no longer meets the balance requirements for Institutional Shares, Vanguard may automatically convert the shares in the account to Investor Shares. A decline in the account balance because of market movement may result in such a conversion. Vanguard will notify the investor in writing before any mandatory conversion occurs.

Redeeming Shares

How to Initiate a Redemption Request

Be sure to check Exchanging Shares, Frequent-Trading Limitations, and Other Rules You Should Know before placing your redemption request.

Online. You may request a redemption of shares or request an exchange through our website or our mobile application if you are registered for online access.

By telephone. You may call Vanguard to request a redemption of shares or an exchange. See Contacting Vanguard.

By mail. You may send a written request to Vanguard to redeem from a fund account or to make an exchange. See Contacting Vanguard.

How to Receive Redemption Proceeds

By electronic bank transfer. You may have the proceeds of a fund redemption sent directly to a designated bank account. To establish the electronic bank transfer service on an account, you must designate a bank account online, complete a special form, or fill out the appropriate section of your account registration form. After the service is set up on your account, you can redeem shares by electronic bank transfer on a regular schedule (Automatic Withdrawal Plan) or upon request. Your redemption request can be initiated online (if you are registered for online access), by telephone, or by mail.

By wire. To receive your proceeds by wire, you may instruct Vanguard to wire your redemption proceeds ($100 minimum) to a previously designated bank account. To establish the wire redemption service, you generally must designate a bank account

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online, complete a special form, or fill out the appropriate section of your account registration form.

By exchange. You may have the proceeds of a Vanguard fund redemption invested directly in shares of another Vanguard fund. You may initiate an exchange online (if you are registered for online access), by telephone, or by mail. See Exchanging Shares.

By check. If you have not chosen another redemption method, Vanguard will mail you a redemption check, generally payable to all registered account owners, normally within two business days of your trade date, and generally to the address of record.

Trade Date

The trade date for any redemption request received in good order will depend on the day and time Vanguard receives your request and the manner in which you are redeeming. Your redemption will be executed using the NAV as calculated on the trade date. NAVs are calculated only on days that the NYSE is open for trading (a business day).

For redemptions by check, exchange, or wire: If the redemption request is received by Vanguard on a business day before the close of regular trading on the NYSE (generally 4 p.m., Eastern time), the trade date will be the same day. If the redemption request is received on a business day after the close of regular trading on the NYSE, or on a nonbusiness day, the trade date will be the next business day.

• Note on timing of wire redemptions from money market funds: For telephone requests received by Vanguard on a business day before 10:45 a.m., Eastern time (2 p.m., Eastern time, for Vanguard Prime Money Market Fund), the redemption proceeds generally will leave Vanguard by the close of business the same day. For telephone requests received by Vanguard on a business day after those cut-off times, or on a nonbusiness day, and for all requests other than by telephone, the redemption proceeds generally will leave Vanguard by the close of business on the next business day.

• Note on timing of wire redemptions from all other funds: For requests received by Vanguard on a business day before the close of regular trading on the NYSE (generally 4 p.m., Eastern time), the redemption proceeds generally will leave Vanguard by the close of business on the next business day. For requests received by Vanguard on a business day after the close of regular trading on the NYSE, or on a nonbusiness day, the redemption proceeds generally will leave Vanguard by the close of business on the second business day after Vanguard receives the request.

For redemptions by electronic bank transfer using an Automatic Withdrawal Plan: Your trade date generally will be the date you selected for withdrawal of funds (redemption of shares) from your Vanguard account. Proceeds of redeemed shares generally will be credited to your designated bank account two business days after

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your trade date. If the date you selected for withdrawal of funds from your Vanguard account falls on a weekend, holiday, or other nonbusiness day, your trade date generally will be the previous business day. For retirement accounts, if the date you selected for withdrawal of funds from your Vanguard account falls on the last day of the year and if that date is a holiday, your trade date will be the first business day of the following year. Please note that if you designate the first of the month for automated withdrawals, trades designated for January 1 will receive the next business day’s trade date.

For redemptions by electronic bank transfer not using an Automatic Withdrawal Plan: If the redemption request is received by Vanguard on a business day before the close of regular trading on the NYSE (generally 4 p.m., Eastern time), the trade date will be the same day. If the redemption request is received on a business day after the close of regular trading on the NYSE, or on a nonbusiness day, the trade date will be the next business day.

If your redemption request is not accurate and complete, it may be rejected. If we are unable to send your redemption proceeds by wire or electronic bank transfer because the receiving institution rejects the transfer, Vanguard will make additional efforts to complete your transaction. If Vanguard is still unable to complete the transaction, we may send the proceeds of the redemption to you by check, generally payable to all registered account owners, or use your proceeds to purchase new shares of the fund from which you sold shares for the purpose of the wire or electronic bank transfer transaction. See Other Rules You Should Know—Good Order.

For further information about redemption transactions, consult our website at vanguard.com or see Contacting Vanguard.

Other Redemption Rules You Should Know

Documentation for certain accounts. Special documentation may be required to redeem from certain types of accounts, such as trust, corporate, nonprofit, or retirement accounts. Please call us before attempting to redeem from these types of accounts.

Potentially disruptive redemptions. Vanguard reserves the right to pay all or part of a redemption in kind—that is, in the form of securities—if we reasonably believe that a cash redemption would negatively affect the fund’s operation or performance or that the shareholder may be engaged in market-timing or frequent trading. Under these circumstances, Vanguard also reserves the right to delay payment of the redemption proceeds for up to seven calendar days. By calling us before you attempt to redeem a large dollar amount, you may avoid in-kind or delayed payment of your redemption. Please see Frequent-Trading Limitations for information about Vanguard’s policies to limit frequent trading.

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Recently purchased shares. Although you can redeem shares at any time, proceeds may not be made available to you until the fund collects payment for your purchase. This may take up to seven calendar days for shares purchased by check or by electronic bank transfer. If you have written a check on a fund with checkwriting privileges, that check may be rejected if your fund account does not have a sufficient available balance.

Address change. If you change your address online or by telephone, there may be up to a 14-day restriction on your ability to request check redemptions online and by telephone. You can request a redemption in writing at any time. Confirmations of address changes are sent to both the old and new addresses.

Payment to a different person or address. At your request, we can make your redemption check payable, or wire your redemption proceeds, to a different person or send it to a different address. However, this generally requires the written consent of all registered account owners and may require additional documentation, such as a signature guarantee or a notarized signature. You may obtain a signature guarantee from some commercial or savings banks, credit unions, trust companies, or member firms of a U.S. stock exchange.

No cancellations. Vanguard will not accept your request to cancel any redemption request once processing has begun. Please be careful when placing a redemption request.

Emergency circumstances. Vanguard funds can postpone payment of redemption proceeds for up to seven calendar days. In addition, Vanguard funds can suspend redemptions and/or postpone payments of redemption proceeds beyond seven calendar days at times when the NYSE is closed or during emergency circumstances, as determined by the SEC.

Exchanging Shares

An exchange occurs when you use the proceeds from the redemption of shares of one Vanguard fund to simultaneously purchase shares of a different Vanguard fund. You can make exchange requests online (if you are registered for online access), by telephone, or by mail. See Purchasing Shares and Redeeming Shares.

If the NYSE is open for regular trading (generally until 4 p.m., Eastern time, on a business day) at the time an exchange request is received in good order, the trade date generally will be the same day. See Other Rules You Should Know—Good Order for additional information on all transaction requests.

Vanguard will not accept your request to cancel any exchange request once processing has begun. Please be careful when placing an exchange request.

Please note that Vanguard reserves the right, without notice, to revise or terminate the exchange privilege, limit the amount of any exchange, or reject an exchange, at

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any time, for any reason. See Frequent-Trading Limitations for additional restrictions on exchanges.

Frequent-Trading Limitations

Because excessive transactions can disrupt management of a fund and increase the fund’s costs for all shareholders, the board of trustees of each Vanguard fund places certain limits on frequent trading in the funds. Each Vanguard fund (other than money market funds and short-term bond funds, but including Vanguard Short-Term Inflation-Protected Securities Index Fund) limits an investor’s purchases or exchanges into a fund account for 30 calendar days (60 calendar days for participants in employer-sponsored defined contribution plans recordkept directly by Vanguard) after the investor has redeemed or exchanged out of that fund account. ETF Shares are not subject to these frequent-trading limits.

For Vanguard Retirement Investment Program pooled plans, the limitations apply to exchanges made online or by telephone.

These frequent-trading limitations do not apply to the following:

• Purchases of shares with reinvested dividend or capital gains distributions.

• Transactions through Vanguard’s Automatic Investment Plan, Automatic Exchange Service, Direct Deposit Service, Automatic Withdrawal Plan, Required Minimum Distribution Service, and Vanguard Small Business Online^®.

• Discretionary transactions through Vanguard Asset Management Services, Vanguard Personal Advisor Services, and Vanguard Institutional Advisory Services^®.

• Redemptions of shares to pay fund or account fees.

• Redemptions of shares to remove excess shareholder contributions to certain types of retirement accounts (including, but not limited to, IRAs, certain Individual 403(b)(7) Custodial Accounts, and Vanguard Individual 401(k) Plans).

• Transaction requests submitted by mail to Vanguard from shareholders who hold their accounts directly with Vanguard or through a Vanguard brokerage account. (Transaction requests submitted by fax, if otherwise permitted, are subject to the limitations.)

• Transfers and reregistrations of shares within the same fund.

• Purchases of shares by asset transfer or direct rollover.

• Conversions of shares from one share class to another in the same fund.

• Checkwriting redemptions.

• Section 529 college savings plans.

• Certain approved institutional portfolios and asset allocation programs, as well as trades made by funds or trusts managed by Vanguard or its affiliates that invest in

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other Vanguard funds. (Please note that shareholders of Vanguard’s funds of funds are subject to the limitations.)

For participants in employer-sponsored defined contribution plans,* the frequent-trading limitations do not apply to:

• Purchases of shares with participant payroll or employer contributions or loan repayments.

• Purchases of shares with reinvested dividend or capital gains distributions.

• Distributions, loans, and in-service withdrawals from a plan.

• Redemptions of shares as part of a plan termination or at the direction of the plan.

• Transactions executed through the Vanguard Managed Account Program.

• Redemptions of shares to pay fund or account fees.

• Share or asset transfers or rollovers.

• Reregistrations of shares.

• Conversions of shares from one share class to another in the same fund.

• Exchange requests submitted by written request to Vanguard. (Exchange requests submitted by fax, if otherwise permitted, are subject to the limitations.)

* The following Vanguard fund accounts are subject to the frequent-trading limitations: SEP-IRAs, SIMPLE IRAs, certain Individual 403(b)(7) Custodial Accounts, and Vanguard Individual 401(k) Plans.

Accounts Held by Institutions (Other Than Defined Contribution Plans)

Vanguard will systematically monitor for frequent trading in institutional clients’ accounts. If we detect suspicious trading activity, we will investigate and take appropriate action, which may include applying to a client’s accounts the 30-day policy previously described, prohibiting a client’s purchases of fund shares, and/or revoking the client’s exchange privilege.

Accounts Held by Intermediaries

When intermediaries establish accounts in Vanguard funds for the benefit of their clients, we cannot always monitor the trading activity of the individual clients. However, we review trading activity at the intermediary (omnibus) level, and if we detect suspicious activity, we will investigate and take appropriate action. If necessary, Vanguard may prohibit additional purchases of fund shares by an intermediary, including for the benefit of certain of the intermediary’s clients. Intermediaries also may monitor their clients’ trading activities with respect to Vanguard funds.

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For those Vanguard funds that charge purchase and/or redemption fees, intermediaries will be asked to assess these fees on client accounts and remit these fees to the funds. The application of purchase and redemption fees and frequent-trading limitations may vary among intermediaries. There are no assurances that Vanguard will successfully identify all intermediaries or that intermediaries will properly assess purchase and redemption fees or administer frequent-trading limitations. If you invest with Vanguard through an intermediary, please read that firm’s materials carefully to learn of any other rules or fees that may apply.

Other Rules You Should Know

Prospectus and Shareholder Report Mailings

When two or more shareholders have the same last name and address, just one summary prospectus (or prospectus) and/or shareholder report may be sent in an attempt to eliminate the unnecessary expense of duplicate mailings. You may request individual prospectuses and reports by contacting our Client Services Department in writing, by telephone, or online. See Contacting Vanguard.

Vanguard.com

Registration. If you are a registered user of vanguard.com, you can review your account holdings; buy, sell, or exchange shares of most Vanguard funds; and perform most other transactions through our website. You must register for this service online.

Electronic delivery. Vanguard can deliver your account statements, transaction confirmations, prospectuses, tax forms, and shareholder reports electronically. If you are a registered user of vanguard.com, you can consent to the electronic delivery of these documents by logging on and changing your mailing preferences under “Account Maintenance.” You can revoke your electronic consent at any time through our website, and we will begin to send paper copies of these documents within 30 days of receiving your revocation.

Telephone Transactions

Automatic. When we set up your account, we will automatically enable you to do business with us by telephone, unless you instruct us otherwise in writing.

Tele-Account^®. To obtain fund and account information through Vanguard’s automated telephone service, you must first establish a Personal Identification Number (PIN) by calling Tele-Account at 800-662-6273.

Proof of a caller’s authority. We reserve the right to refuse a telephone request if the caller is unable to provide the requested information or if we reasonably believe

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that the caller is not an individual authorized to act on the account. Before we allow a caller to act on an account, we may request the following information:

• Authorization to act on the account (as the account owner or by legal documentation or other means).

• Account registration and address.

• Fund name and account number, if applicable.

• Other information relating to the caller, the account owner, or the account.

Good Order

We reserve the right to reject any transaction instructions that are not in “good order.” Good order generally means that your instructions:

• Are provided by the person(s) authorized in accordance with Vanguard’s policies and procedures to access the account and request transactions.

• Include the fund name and account number.

• Include the amount of the transaction (stated in dollars, shares, or percentage).

Written instructions also must generally include:

• An original signature and date from the authorized person(s).

• Signature guarantees or notarized signatures, if required for the type of transaction.

(Call Vanguard for specific requirements.)

• Any supporting documentation that may be required.

Written instructions are acceptable when a Vanguard form is not applicable. The requirements vary among types of accounts and transactions. For more information, consult our website at vanguard.com or see Contacting Vanguard.

Vanguard reserves the right, without notice, to revise the requirements for good order.

Future Trade-Date Requests

Vanguard does not accept requests to hold a purchase, conversion, redemption, or exchange transaction for a future date. All such requests will receive trade dates as previously described in Purchasing Shares, Converting Shares, Redeeming Shares, and

Exchanging Shares. Vanguard reserves the right to return future-dated purchase checks.

Accounts With More Than One Owner

If an account has more than one owner or authorized person, Vanguard generally will accept instructions from any one owner or authorized person.

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Responsibility for Fraud

Vanguard will not be responsible for any account losses because of fraud if we reasonably believe that the person transacting business on an account is authorized to do so. Please take precautions to protect yourself from fraud. Keep your account information private, and immediately review any account statements or other information that we provide to you. It is important that you contact Vanguard immediately about any transactions or changes to your account that you believe to be unauthorized.

Uncashed Checks

Please cash your distribution or redemption checks promptly. Vanguard will not pay interest on uncashed checks. Vanguard may be required to transfer assets related to uncashed checks to a state under the state’s abandoned property law.

Dormant Accounts

If your account has no activity in it for a period of time, Vanguard may be required to transfer it to a state under the state’s abandoned property law.

Unusual Circumstances

If you experience difficulty contacting Vanguard online or by telephone, you can send us your transaction request by regular or express mail. See Contacting Vanguard for addresses.

Investing With Vanguard Through Other Firms

You may purchase or sell shares of most Vanguard funds through a financial intermediary, such as a bank, a broker, or an investment advisor. Please consult your financial intermediary to determine which, if any, shares are available through that firm and to learn about other rules that may apply. Your financial intermediary can provide you with account information and any required tax forms.

Please see Frequent-Trading Limitations—Accounts Held by Intermediaries for information about the assessment of any purchase or redemption fees and the monitoring of frequent trading for accounts held by intermediaries.

Account Service Fee

Vanguard charges a $20 account service fee on fund accounts that have a balance below $10,000 for any reason, including market fluctuation. The account service fee applies to both retirement and nonretirement fund accounts and will be assessed on fund accounts in all Vanguard funds, regardless of the account minimum. The fee, which will be collected by redeeming fund shares in the amount of $20, will be deducted from a fund account only once per calendar year.

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If you register on vanguard.com and elect to receive electronic delivery of statements, reports, and other materials for all of your fund accounts, the account service fee for balances below $10,000 will not be charged, so long as that election remains in effect.

The account service fee also does not apply to the following:

• Money market sweep accounts owned in connection with a Vanguard Brokerage Services^® account.

• Accounts held through intermediaries.

• Accounts held by institutional clients.

• Accounts held by Voyager, Voyager Select, Flagship, and Flagship Select clients.

Eligibility is based on total household assets held at Vanguard, with a minimum of $50,000 to qualify for Vanguard Voyager Services^®, $500,000 for Vanguard Voyager Select Services^®, $1 million for Vanguard Flagship Services^®, and $10 million for Vanguard Flagship Select Services^™. Vanguard determines eligibility by aggregating assets of all qualifying accounts held by the investor and immediate family members who reside at the same address. Aggregate assets include investments in Vanguard mutual funds, Vanguard ETFs^®, certain annuities through Vanguard, the Vanguard 529 Plan, and certain small-business accounts. Assets in employer-sponsored retirement plans for which Vanguard provides recordkeeping services may be included in determining eligibility if the investor also has a personal account holding Vanguard mutual funds. Note that assets held in a Vanguard Brokerage Services account (other than Vanguard funds, including Vanguard ETFs) are not included when determining a household’s eligibility.

• Participant accounts in employer-sponsored defined contribution plans.* Please consult your enrollment materials for the rules that apply to your account.

• Section 529 college savings plans.

* The following Vanguard fund accounts have alternative fee structures: SIMPLE IRAs, certain Individual 403(b)(7) Custodial Accounts, Vanguard Retirement Investment Program pooled plans, and Vanguard Individual 401(k) Plans.

Low-Balance Accounts

The Fund reserves the right to liquidate a fund account whose balance falls below the account minimum for any reason, including market fluctuation. This liquidation policy applies to nonretirement fund accounts and accounts that are held through intermediaries. Any such liquidation will be preceded by written notice to the investor.

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Right to Change Policies

In addition to the rights expressly stated elsewhere in this prospectus, Vanguard reserves the right, without notice, to (1) alter, add, or discontinue any conditions of purchase (including eligibility requirements), redemption, exchange, conversion, service, or privilege at any time; (2) accept initial purchases by telephone; (3) freeze any account and/or suspend account services if Vanguard has received reasonable notice of a dispute regarding the assets in an account, including notice of a dispute between the registered or beneficial account owners, or if Vanguard reasonably believes a fraudulent transaction may occur or has occurred; (4) temporarily freeze any account and/or suspend account services upon initial notification to Vanguard of the death of the shareholder until Vanguard receives required documentation in good order; (5) alter, impose, discontinue, or waive any purchase fee, redemption fee, account service fee, or other fees charged to a group of shareholders; and (6) redeem an account or suspend account privileges, without the owner’s permission to do so, in cases of threatening conduct or activity Vanguard believes to be suspicious, fraudulent, or illegal. Changes may affect any or all investors. These actions will be taken when, at the sole discretion of Vanguard management, Vanguard reasonably believes they are deemed to be in the best interest of a fund.

Share Classes

Vanguard reserves the right, without notice, to change the eligibility requirements of its share classes, including the types of clients who are eligible to purchase each share class.

Fund and Account Updates

Confirmation Statements

We will send (or provide through our website, whichever you prefer) a confirmation of your trade date and the amount of your transaction when you buy, sell, exchange, or convert shares. However, we will not send confirmations reflecting only checkwriting redemptions or the reinvestment of dividend or capital gains distributions. For any month in which you had a checkwriting redemption, a Checkwriting Activity Statement will be sent to you itemizing the checkwriting redemptions for that month. Promptly review each confirmation statement that we provide to you. It is important that you contact Vanguard immediately with any questions you may have about any transaction reflected on a confirmation statement, or Vanguard will consider the transaction properly processed.

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Portfolio Summaries

We will send (or provide through our website, whichever you prefer) quarterly portfolio summaries to help you keep track of your accounts throughout the year. If you prefer, you may request to receive monthly portfolio summaries. Each summary shows the market value of your account at the close of the statement period, as well as all distributions, purchases, redemptions, exchanges, transfers, and conversions for the current calendar quarter (or month). Promptly review each summary that we provide to you. It is important that you contact Vanguard immediately with any questions you may have about any transaction reflected on the summary, or Vanguard will consider the transaction properly processed.

Tax Information Statements

For most accounts, we are required to provide annual tax forms to assist you in preparing your income tax returns. We will send (or provide through our website, whichever you prefer) tax forms for each calendar year early in the following year. Registered users of vanguard.com can also view these forms through our website. Vanguard may also provide you with additional tax-related documentation. For more information, consult our website at vanguard.com or see Contacting Vanguard.

Annual and Semiannual Reports

We will send (or provide through our website, whichever you prefer) reports about Vanguard Market Neutral Fund twice a year, in February and August. These reports include overviews of the financial markets and provide the following specific Fund information:

• Performance assessments and comparisons with industry benchmarks.

• Reports from the advisor.

• Financial statements with listings of Fund holdings.

Portfolio Holdings

Please consult the Fund’s Statement of Additional Information or our website for a description of the policies and procedures that govern disclosure of the Fund’s portfolio holdings.

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Vanguard Addresses

Please be sure to use the correct address. Use of an incorrect address could delay the processing of your transaction.

CFA^® is a registered trademark owned by CFA Institute.

Morningstar data © 2016 Morningstar, Inc. All Rights Reserved. The information contained herein: (1) is proprietary to Morningstar and/or its content providers; (2) may not be copied or distributed; and (3) is not warranted to be accurate, complete or timely. Neither Morningstar nor its content providers are responsible for any damages or losses arising from any use of this information. Past performance is no guarantee of future results.

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Glossary of Investment Terms

Borrowing Expense on Securities Sold Short. A fee charged by a fund’s broker when a fund sells a stock short. This fee is calculated on a daily basis, based upon the market value of the stock sold short and a variable rate that is dependent upon the availability of the stock.

Capital Gains Distribution. Payment to mutual fund shareholders of gains realized on securities that a fund has sold at a profit, minus any realized losses.

Cash Equivalent Investments. Cash deposits, short-term bank deposits, and money market instruments that include U.S. Treasury bills and notes, bank certificates of deposit (CDs), repurchase agreements, commercial paper, and banker’s acceptances.

Citigroup 3-Month U.S. Treasury Bill Index. An index that measures performance of short-term U.S. government debt securities.

Common Stock. A security representing ownership rights in a corporation.

Dividend Distribution. Payment to mutual fund shareholders of income from interest or dividends generated by a fund’s investments.

Dividend Expense on Securities Sold Short. The amount of money that a fund is required to pay to a lender of stock that the fund has sold short when a dividend has been declared on the stock.

Expense Ratio. A fund’s total annual operating expenses expressed as a percentage of the fund’s average net assets. The expense ratio includes management and administrative expenses, but it does not include the transaction costs of buying and selling portfolio securities.

Inception Date. The date on which the assets of a fund (or one of its share classes) are first invested in accordance with the fund’s investment objective. For funds with a subscription period, the inception date is the day after that period ends. Investment performance is generally measured from the inception date.

Mutual Fund. An investment company that pools the money of many people and invests it in a variety of securities in an effort to achieve a specific objective over time.

Quantitative Process. An assessment of specific measurable factors, such as cost of capital; value of assets; and projections of sales, costs, earnings, and profits. The use of a quantitative process provides a systematic approach to investment decisions and portfolios.

Securities. Stocks, bonds, money market instruments, and other investments.

Short Sale. A transaction in which a fund sells a stock it does not own and then borrows the stock from a lender in order to settle the transaction. A fund will engage in short sales when its advisor believes that the price of the stock will decline or underperform.

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Total Return. A percentage change, over a specified time period, in a mutual fund’s net asset value, assuming the reinvestment of all distributions of dividends and capital gains.

Volatility. The fluctuations in value of a mutual fund or other security. The greater a fund’s volatility, the wider the fluctuations in its returns.

Yield. Income (interest or dividends) earned by an investment, expressed as a percentage of the investment’s price.

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P.O. Box 2600

Valley Forge, PA 19482-2600

© 2016 The Vanguard Group, Inc. All rights reserved. Vanguard Marketing Corporation, Distributor.

P 634 042016

Fund Summary

Investment Objective

The Fund seeks to provide long-term capital appreciation while limiting exposure to general stock market risk.

Fees and Expenses

The following table describes the fees and expenses you may pay if you buy and hold Institutional Shares of the Fund.

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Example

The following example is intended to help you compare the cost of investing in the Fund’s Institutional Shares with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you invested $10,000 in the Fund’s shares. This example assumes that the Shares provide a return of 5% each year and that total annual fund operating expenses remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you redeem your investment at the end of the given 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” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in more taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the previous expense example, reduce the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 68% of the average value of its portfolio.

Principal Investment Strategies

The Fund follows a market neutral strategy, which the Fund defines as a strategy designed to produce a portfolio that is neutral with respect to general stock market risk (sometimes referred to as beta neutrality). Beta is a measure of a portfolio’s volatility relative to the volatility of the general stock market. The Fund, as a whole, does not seek to adhere to any other definition of market neutrality.

To implement the strategy, the advisor buys securities that it believes offer an appropriate balance between strong growth prospects and reasonable valuations relative to their industry peers and sells short securities that it considers to be overvalued, in amounts that it believes will achieve market neutrality. By taking long and short positions in different securities, the Fund attempts to limit the effect of market movements on portfolio performance. The advisor does this by using a quantitative process and may, at any time, buy or sell short any number of publicly traded, exchange-listed equity securities and may emphasize specific industries, styles (growth/value), capitalization ranges, countries, or other factors. The overall performance of the Fund depends on the net performance of its long and short positions, and it is possible for the Fund to experience a net loss across all positions. If the Fund’s investment strategy is successful, however, the net performance of its long

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and short positions will produce long-term capital appreciation that reflects the quality of the advisor’s security selections, with limited exposure to general stock market risk.

The Fund’s long/short market neutral investment strategy is an absolute-return investment approach seeking performance that exceeds the returns of 3-month U.S. Treasury bills. An investment in the Fund, however, is different from an investment in 3-month U.S. Treasury bills because, among other things, U.S. Treasury bills are backed by the full faith and credit of the U.S. government, U.S. Treasury bills have a fixed rate of return, investors in U.S. Treasury bills have a very low risk of losing their investment, and an investment in the Fund is expected to be substantially more volatile than an investment in U.S. Treasury bills.

Because of the Fund’s market neutral strategy, the Fund’s overall price movements are not expected to correlate with the general stock market’s price movements. In other words, the Fund is expected to have returns that are independent of the returns and direction of the general stock market.

Principal Risks

An investment in the Fund could lose money over short or even long periods, and the entire amount invested could be lost. There can be no assurance that the Fund’s investment objective or strategies will be achieved, and results may vary substantially over time. The Fund is subject to the following risks, which could affect the Fund’s performance:

• Strategy risk, which is the chance that the Fund’s investment strategy will not succeed. There is no guarantee that the Fund will be able to limit exposure to general stock market risk or produce returns that exceed the returns of 3-month U.S. Treasury bills. The Fund’s use of short sales in combination with its long positions in an attempt to improve performance or to reduce overall portfolio risk may not be successful and may result in greater losses or lower positive returns than if the Fund held only long positions. When the general stock market is performing strongly, the Fund is expected to underperform the market because the Fund’s short positions will likely lose money. If the Fund’s market neutral strategy is unsuccessful, the Fund may be subject to stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices.

• Short-selling risk, which is the chance that the Fund will lose money in connection with its short sales of securities. Short selling allows an investor to profit from declines in the prices of securities. To engage in a short sale, the Fund must “borrow” securities for a fee. To close out short positions, the Fund may have to sell related long positions at disadvantageous times to produce cash to unwind a short position. There is no guarantee that the price of the borrowed securities will decline; in fact, it may rise. The Fund’s loss on a short sale is theoretically unlimited, because there is no upward limit on the price a borrowed security could attain. Short selling involves

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higher transaction costs than long-only investing, which could offset any gains and increase any losses.

• Manager risk, which is the chance that poor security selection or strategy execution will cause the Fund to fail to achieve its investment objective or to underperform other funds with a similar investment strategy. The advisor’s security selection process may not eliminate all stock market risk factors associated with the long and short positions it establishes for the Fund. It is possible that the stocks the Fund holds long will decline in value at the same time that the stocks it holds short increase in value, thereby increasing potential losses to the Fund. Any gain from a short position may be partially or totally offset by a decline in a long position, or vice versa.

• Investment risk, which is the chance that the Fund’s advisor will take positions in securities, intentionally or unintentionally, that increase the Fund’s sensitivity to certain investment factors. These factors may include, but are not limited to, market capitalization ranges, styles (growth/value), and industries of the underlying securities. These factors may cause the Fund to fail to achieve its investment objective of limiting exposure to general stock market risk or cause it to underperform other funds with a similar investment strategy.

• Derivatives risk. The Fund may invest in derivatives, which may involve risks different from, and possibly greater than, those of investments directly in the underlying securities or assets.

An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Annual Total Returns

The following bar chart and table are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund‘s Institutional Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Institutional Shares compare with those of a relevant market index and a comparative benchmark, which have investment characteristics similar to those of the Fund. Returns for the Equity Market Neutral Funds Average are derived from data provided by Lipper, a Thomson Reuters Company. Keep in mind that the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future. Updated performance information is available on our website at vanguard.com/performance or by calling Vanguard toll-free at 800-662-7447.

The performance figures in this section for the periods prior to November 30, 2007, are those of the Fund’s predecessor fund, Laudus Rosenberg U.S. Large/Mid Capitalization Long/Short Equity Fund (Laudus Fund). The Laudus Fund was sponsored and managed by Charles Schwab Investment Management, Inc., and sub-advised by AXA Rosenberg Investment Management LLC (AXA Rosenberg). The Laudus Fund was reorganized

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with and into Vanguard Market Neutral Fund on November 30, 2007. The Fund continues to operate as a market neutral fund and maintains a substantially similar investment objective and substantially similar principal investment strategies to those of the Laudus Fund, except that, effective July 25, 2008, the Fund revised its investment strategies to focus on beta neutrality and to enable the Fund to invest to a greater extent in foreign securities. In addition, effective April 30, 2010, the Fund’s investment advisory team was restructured, which was also reflected in its investment strategies.

Annual Total Returns — Vanguard Market Neutral Fund Institutional Shares

During the periods shown in the bar chart, the highest return for a calendar quarter was 8.86% (quarter ended December 31, 2007), and the lowest return for a quarter was –6.53% (quarter ended March 31, 2009).

Average Annual Total Returns for Periods Ended December 31, 2015

Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. When after-tax returns are calculated, it is assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local

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income taxes are not reflected in the calculations. Please note that after-tax returns are not relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. Also, figures captioned Return After Taxes on Distributions and Sale of Fund Shares may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.

Investment Advisor

The Vanguard Group, Inc. (Vanguard)

Portfolio Managers

James P. Stetler, Principal of Vanguard. He has co-managed the Fund since 2012.

Michael R. Roach, CFA, Portfolio Manager at Vanguard. He has co-managed the Fund since 2012.

Binbin Guo, Ph.D., Principal of Vanguard and head of Equity Research and Portfolio Strategies of Vanguard’s Quantitative Equity Group. He has co-managed the Fund since 2016.

Purchase and Sale of Fund Shares

You may purchase or redeem shares online through our website (vanguard.com), by mail (The Vanguard Group, P.O. Box 1110, Valley Forge, PA 19482-1110), or by telephone (800-662-2739). The minimum investment amount required to open and maintain a Fund account for Institutional Shares is $5 million. The minimum investment amount required to add to an existing Fund account is generally $1.

Tax Information

The Fund’s distributions may be taxable as ordinary income or capital gain. If you are investing through a tax-deferred retirement account, such as an IRA, special tax rules apply.

Payments to Financial Intermediaries

The Fund and its investment advisor do not pay financial intermediaries for sales of Fund shares.

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More on the Fund

This prospectus describes the principal risks you would face as a Fund shareholder. It is important to keep in mind one of the main axioms of investing: generally, the higher the risk of losing money, the higher the potential reward. The reverse, also, is generally true: the lower the risk, the lower the potential reward. As you consider an investment in any mutual fund, you should take into account your personal tolerance for fluctuations in the securities markets. Look for this symbol throughout the prospectus. It is used to mark detailed information about the more significant risks that you would confront as a Fund shareholder. To highlight terms and concepts important to mutual fund investors, we have provided Plain Talk^® explanations along the way. Reading the prospectus will help you decide whether the Fund is the right investment for you. We suggest that you keep this prospectus for future reference.

Share Class Overview

This prospectus offers the Fund’s Institutional Shares, which are generally for investors who invest a minimum of $5 million. A separate prospectus offers the Fund’s Investor Shares, which generally have an investment minimum of $250,000.

Both share classes offered by the Fund have the same investment objective, strategies, and policies. However, different share classes have different expenses; as a result, their investment performances will differ.

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The following sections explain the principal investment strategies and policies that the Fund uses in pursuit of its objective. The Fund‘s board of trustees, which oversees the Fund’s management, may change investment strategies or policies in the interest of shareholders without a shareholder vote, unless those strategies or policies are designated as fundamental. Note that the Fund’s investment objective is not fundamental and may be changed without a shareholder vote.

An investment in the Fund could lose money over short or even long periods, and the entire amount invested could be lost. There can be no assurance that the Fund’s investment objective or strategies will be achieved, and results may vary substantially over time.

Security Selection

The Vanguard Group, Inc. (Vanguard), the Fund’s investment advisor, selects and maintains a diversified portfolio of common stocks for the Fund. The advisor employs active investment management methods, which means that securities are bought and sold according to the advisor’s evaluations of companies and their financial prospects, the prices of the securities, and the stock market and the economy in general.

The Fund follows a market neutral strategy, which the Fund defines as a strategy designed to produce a portfolio that is neutral with respect to general stock market risk (sometimes referred to as beta neutrality). Beta is a measure of a portfolio’s volatility relative to the volatility of the general stock market. The Fund, as a whole, does not seek to adhere to any other definition of market neutrality. By taking long and short positions in different securities, the Fund attempts to limit the effect of market movements on portfolio performance. The advisor may, at any time, buy or sell short any number of publicly traded, exchange-listed equity securities and may emphasize specific industries, styles (growth/value), capitalization ranges, countries, or other factors. The overall performance of the Fund depends on the net performance of its long and short positions, and it is possible for the Fund to experience a net loss across all positions. If the Fund’s investment strategy is successful, however, the net performance of its long and short positions will produce long-term capital appreciation that reflects the quality of the advisor’s security selections, with limited exposure to general stock market risk.

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To implement the strategy, Vanguard buys securities that it believes offer an appropriate balance between strong growth prospects and reasonable valuations relative to their industry peers and sells short securities that it considers to be overvalued, in amounts that it believes will achieve market neutrality. Vanguard manages the portfolio through the use of a quantitative process that was developed by a team of Vanguard researchers. This process is continually evolving. All potential enhancements to the process go through rigorous peer vetting and validation before being implemented. A team of portfolio managers utilizes the resulting process to determine which securities to buy long and sell short in the portfolio.

The Fund is subject to strategy risk, which is the chance that the Fund’s investment strategy will not succeed. There is no guarantee that the Fund will be able to limit exposure to general stock market risk or produce returns that exceed the returns of 3-month U.S. Treasury bills. The Fund’s use of short sales in combination with its long positions in an attempt to improve performance or to reduce overall portfolio risk may not be successful and may result in greater losses or lower positive returns than if the Fund held only long positions. When the general stock market is performing strongly, the Fund is expected to underperform the market because the Fund’s short positions will likely lose money. If the Fund’s market neutral strategy is unsuccessful, the Fund may be subject to stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices.

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The Fund is subject to short-selling risk, which is the chance that the Fund will lose money in connection with its short sales of securities. Short selling allows an investor to profit from declines in the prices of securities. To engage in a short sale, the Fund must “borrow” securities for a fee. To close out short positions, the Fund may have to sell related long positions at disadvantageous times to produce cash to unwind a short position. There is no guarantee that the price of the borrowed securities will decline; in fact, it may rise. The Fund’s loss on a short sale is theoretically unlimited, because there is no upward limit on the price a borrowed security could attain. Short selling involves higher transaction costs than long-only investing, which could offset any gains and increase any losses.

The market value of the long and short positions in the Fund will not always be equal because of continuous changes in the prices of securities. The Fund expects that the advisor will need to frequently rebalance its long and short positions. The Fund’s holdings will also need to reflect changes in the universe of securities the advisor considers undervalued or overvalued. As a result, the Fund is expected to experience a high portfolio turnover rate, possibly in excess of 100%.

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The Fund is subject to manager risk, which is the chance that poor security selection or strategy execution will cause the Fund to fail to achieve its investment objective or to underperform other funds with a similar investment strategy. The advisor’s security selection process may not eliminate all stock market risk factors associated with the long and short positions it establishes for the Fund. It is possible that the stocks the Fund holds long will decline in value at the same time that the stocks it holds short increase in value, thereby increasing potential losses to the Fund. Any gain from a short position may be partially or totally offset by a decline in a long position, or vice versa.

The Fund is subject to investment risk, which is the chance that the Fund’s advisor will take positions in securities, intentionally or unintentionally, that increase the Fund’s sensitivity to certain investment factors. These factors may include, but are not limited to, market capitalization ranges, styles (growth/ value), and industries of the underlying securities. These factors may cause the Fund to fail to achieve its investment objective of limiting exposure to general stock market risk or cause it to underperform other funds with a similar investment strategy.

Other Investment Policies and Risks

In addition to investing in publicly traded stocks on a long and short basis, the Fund may make other kinds of investments to achieve its objective.

The Fund may invest in derivatives. In general, investments in derivatives may involve risks different from, and possibly greater than, those of investments directly in the underlying securities or assets.

Generally speaking, a derivative is a financial contract whose value is based on the value of a financial asset (such as a stock, a bond, or a currency), a physical asset (such as gold, oil, or wheat), a market index (such as the S&P 500 Index), or a reference rate (such as LIBOR). The Fund may invest in derivatives only if the expected risks and rewards of the derivatives are consistent with the investment objective, policies, strategies, and risks of the Fund as disclosed in this prospectus. In particular, derivatives will be used only when they may help the advisor:

• Invest in eligible asset classes with greater efficiency and lower cost than is possible through direct investment.

• Add value when these instruments are attractively priced.

The market for many derivatives is, or suddenly can become, illiquid, which may result in significant, rapid, and unpredictable changes in the prices for derivatives. The Fund’s use of a derivative subjects it to the risk of nonperformance by the counterparty,

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potentially resulting in delayed, partial, or even nonpayment of amounts due under the derivative contract.

The Fund‘s derivative investments may include futures contracts and options thereon, options on stocks or stock indexes, warrants, swap agreements, or other derivatives. Losses (or gains) involving futures contracts can sometimes be substantial—in part because a relatively small price movement in a futures contract may result in an immediate and substantial loss (or gain) for a fund. Similar risks exist for other types of derivatives.

Cash Management

The Fund‘s daily cash balance may be invested in one or more Vanguard CMT Funds, which are very low-cost money market funds. When investing in a Vanguard CMT Fund, the Fund bears its proportionate share of the at-cost expenses of the CMT Fund in which it invests. Vanguard receives no additional revenue from Fund assets invested in a Vanguard CMT Fund.

Temporary Investment Measures

The Fund may temporarily depart from its normal investment policies and strategies when the advisor believes that doing so is in the Fund‘s best interest, so long as the alternative is consistent with the Fund‘s investment objective. For instance, the Fund may invest beyond its normal limits in derivatives or exchange-traded funds that are consistent with the Fund‘s objective when those instruments are more favorably priced or provide needed liquidity, as might be the case if the Fund is transitioning assets from one advisor to another or receives large cash flows that it cannot prudently invest immediately.

In addition, the Fund may take temporary defensive positions that are inconsistent with its normal investment policies and strategies—for instance, by allocating substantial assets to cash equivalent investments or other less volatile instruments—in response to adverse or unusual market, economic, political, or other conditions. In

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doing so, the Fund may succeed in avoiding losses but may otherwise fail to achieve its investment objective.

Frequent Trading or Market-Timing

Background. Some investors try to profit from strategies involving frequent trading of mutual fund shares, such as market-timing. For funds holding foreign securities, investors may try to take advantage of an anticipated difference between the price of the fund’s shares and price movements in overseas markets, a practice also known as time-zone arbitrage. Investors also may try to engage in frequent trading of funds holding investments such as small-cap stocks and high-yield bonds. As money is shifted into and out of a fund by a shareholder engaging in frequent trading, the fund incurs costs for buying and selling securities, resulting in increased brokerage and administrative costs. These costs are borne by all fund shareholders, including the long-term investors who do not generate the costs. In addition, frequent trading may interfere with an advisor’s ability to efficiently manage the fund.

Policies to address frequent trading. The Vanguard funds (other than money market funds and short-term bond funds, but including Vanguard Short-Term Inflation-Protected Securities Index Fund) do not knowingly accommodate frequent trading. The board of trustees of each Vanguard fund (other than money market funds and short-term bond funds, but including Vanguard Short-Term Inflation-Protected Securities Index Fund) has adopted policies and procedures reasonably designed to detect and discourage frequent trading and, in some cases, to compensate the fund for the costs associated with it. These policies and procedures do not apply to Vanguard ETF^® Shares because frequent trading in ETF Shares generally does not disrupt portfolio management or otherwise harm fund shareholders. Although there is no assurance that Vanguard will be able to detect or prevent frequent trading or market-timing in all circumstances, the following policies have been adopted to address these issues:

• Each Vanguard fund reserves the right to reject any purchase request—including exchanges from other Vanguard funds—without notice and regardless of size. For example, a purchase request could be rejected because the investor has a history of frequent trading or if Vanguard determines that such purchase may negatively affect a fund’s operation or performance.

• Each Vanguard fund (other than money market funds and short-term bond funds, but including Vanguard Short-Term Inflation-Protected Securities Index Fund) generally prohibits, except as otherwise noted in the Investing With Vanguard section, an investor’s purchases or exchanges into a fund account for 30 calendar days (60 calendar days for participants in employer-sponsored defined contribution plans recordkept directly by Vanguard) after the investor has redeemed or exchanged out of that fund account.

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• Certain Vanguard funds charge shareholders purchase and/or redemption fees on transactions.

See the Investing With Vanguard section of this prospectus for further details on Vanguard’s transaction policies.

Each Vanguard fund (other than money market funds), in determining its net asset value, will use fair-value pricing when appropriate, as described in the Share Price section. Fair-value pricing may reduce or eliminate the profitability of certain frequent-trading strategies.

Do not invest with Vanguard if you are a market-timer.

Turnover Rate

Although the Fund generally seeks to invest for the long term, it may sell securities regardless of how long they have been held. The Financial Highlights section of this prospectus shows historical turnover rates for the Fund. A turnover rate of 100%, for example, would mean that the Fund had sold and replaced securities valued at 100% of its net assets within a one-year period. The average turnover rate for market neutral funds was approximately 289%, as reported by Morningstar, Inc., on December 31, 2015.

The Fund and Vanguard

The Fund is a member of The Vanguard Group, a family of more than 190 mutual funds holding assets of approximately $3 trillion. All of the funds that are members of The Vanguard Group (other than funds of funds) share in the expenses associated with administrative services and business operations, such as personnel, office space, and equipment.

Vanguard Marketing Corporation provides marketing services to the funds. Although shareholders do not pay sales commissions or 12b-1 distribution fees, each fund (other than a fund of funds) or each share class of a fund (in the case of a fund with multiple share classes) pays its allocated share of the Vanguard funds’ marketing costs.

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Investment Advisor

The Vanguard Group, Inc., P.O. Box 2600, Valley Forge, PA 19482, which began operations in 1975, serves as advisor to the Fund through its Quantitative Equity Group. As of December 31, 2015, Vanguard served as advisor for approximately $2.6 trillion in assets. Vanguard provides investment advisory services to the Fund on an at-cost basis, subject to the supervision and oversight of the trustees and officers of the Fund.

For the fiscal year ended December 31, 2015, the advisory expenses represented an effective annual rate of 0.08% of the Fund’s average net assets.

Although the Fund is managed solely by Vanguard, the Fund reserves the right to utilize a multimanager approach in the future. Under the terms of an SEC exemption, the Fund’s board of trustees may, without prior approval from shareholders, change the terms of an advisory agreement or hire a new investment advisor—either as a replacement for an existing advisor or as an additional advisor. Any significant change in the Fund’s advisory arrangements will be communicated to shareholders in writing. As the Fund’s sponsor and overall manager, Vanguard may provide additional investment advisory services to the Fund, on an at-cost basis, at any time. Vanguard may also recommend to the board of trustees that an advisor be hired, terminated, or replaced or that the terms of an existing advisory agreement be revised.

For a discussion of why the board of trustees approved the Fund’s investment advisory arrangement, see the most recent semiannual report to shareholders covering the fiscal period ended June 30.

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The managers primarily responsible for the day-to-day management of the Fund are:

James P. Stetler, Principal of Vanguard. He has been with Vanguard since 1982, has worked in investment management since 1996, has managed investment portfolios since 2003, and has co-managed the Fund since 2012. Education: B.S., Susquehanna University; M.B.A., Saint Joseph’s University.

Michael R. Roach, CFA, Portfolio Manager at Vanguard. He has been with Vanguard since 1998, has worked in investment management since 2001, and has co-managed the Fund since 2012. Education: B.S., Bloomsburg University; M.S., Drexel University.

Binbin Guo, Ph.D., Principal of Vanguard and head of Equity Research and Portfolio Strategies of Vanguard’s Quantitative Equity Group. He has oversight responsibility for the quantitative research team and develops portfolio strategies for equity and alternative asset classes. He has been with Vanguard since 2007 and has co-managed the Fund since 2016. Education: B.S. and M.S., Tsinghua University, China; Ph.D. and M.Phil., Yale University.

The Statement of Additional Information provides information about each portfolio manager’s compensation, other accounts under management, and ownership of shares of the Fund.

Dividends, Capital Gains, and Taxes

Fund Distributions

The Fund distributes to shareholders virtually all of its net income (interest and dividends, less expenses) as well as any net short-term or long-term capital gains realized from the sale of its holdings. Income and capital gains distributions, if any, generally occur annually in December. In addition, the Fund may occasionally make a supplemental distribution at some other time during the year. You can receive distributions of income or capital gains in cash, or you can have them automatically reinvested in more shares of the Fund.

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Basic Tax Points

Vanguard will send you a statement each year showing the tax status of all of your distributions. In addition, investors in taxable accounts should be aware of the following basic federal income tax points:

• Distributions are taxable to you whether or not you reinvest these amounts in additional Fund shares.

• Distributions declared in December—if paid to you by the end of January—are taxable as if received in December.

• Any dividend distribution or short-term capital gains distribution that you receive is taxable to you as ordinary income. If you are an individual and meet certain holding-period requirements with respect to your Fund shares, you may be eligible for reduced tax rates on “qualified dividend income,” if any, distributed by the Fund.

• Any distribution of net long-term capital gains is taxable to you as long-term capital gains, no matter how long you have owned shares in the Fund.

• Capital gains distributions may vary considerably from year to year as a result of the Fund‘s normal investment activities and cash flows.

• A sale or exchange of Fund shares is a taxable event. This means that you may have a capital gain to report as income, or a capital loss to report as a deduction, when you complete your tax return.

• Any conversion between classes of shares of the same fund is a nontaxable event. By contrast, an exchange between classes of shares of different funds is a taxable event.

Individuals, trusts, and estates whose income exceeds certain threshold amounts are subject to a 3.8% Medicare contribution tax on “net investment income.” Net investment income takes into account distributions paid by the Fund and capital gains from any sale or exchange of Fund shares.

Dividend distributions and capital gains distributions that you receive, as well as your gains or losses from any sale or exchange of Fund shares, may be subject to state and local income taxes.

The Fund’s short sales will be subject to tax rules that may affect the amount, timing, and character of distributions to shareholders. This prospectus provides general tax information only. If you are investing through a tax-deferred retirement account, such as an IRA, special tax rules apply. Please consult your tax advisor for detailed information about any tax consequences for you, including potential consequences for you if the Fund simultaneously holds long and short positions with respect to the same security.

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General Information

Backup withholding. By law, Vanguard must withhold 28% of any taxable distributions or redemptions from your account if you do not:

• Provide us with your correct taxpayer identification number.

• Certify that the taxpayer identification number is correct.

• Confirm that you are not subject to backup withholding.

Similarly, Vanguard must withhold taxes from your account if the IRS instructs us to do so.

Foreign investors. Vanguard funds offered for sale in the United States (Vanguard U.S. funds), including the Fund offered in this prospectus, are not widely available outside the United States. Non-U.S. investors should be aware that U.S. withholding and estate taxes and certain U.S. tax reporting requirements may apply to any investments in Vanguard U.S. funds. Foreign investors should visit the Non-U.S. Investors page on our website at vanguard.com for information on Vanguard’s non-U.S. products.

Invalid addresses. If a dividend distribution or capital gains distribution check mailed to your address of record is returned as undeliverable, Vanguard will automatically reinvest the distribution and all future distributions until you provide us with a valid mailing address. Reinvestments will receive the net asset value calculated on the date of the reinvestment.

Share Price

Share price, also known as net asset value (NAV), is calculated each business day as of the close of regular trading on the New York Stock Exchange (NYSE), generally 4 p.m., Eastern time. Each share class has its own NAV, which is computed by dividing the total assets, minus liabilities, allocated to the share class by the number of Fund shares outstanding for that class. On U.S. holidays or other days when the NYSE is

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closed, the NAV is not calculated, and the Fund does not sell or redeem shares. However, on those days the value of the Fund’s assets may be affected to the extent that the Fund holds securities that change in value on those days (such as foreign securities that trade on foreign markets that are open).

Stocks held by a Vanguard fund are valued at their market value when reliable market quotations are readily available from the principal exchange or market on which they are traded. Such securities are generally valued at their official closing price, the last reported sales price, or if there were no sales that day, the mean between the closing bid and asking prices. Certain short-term debt instruments used to manage a fund’s cash may be valued at amortized cost when it approximates fair value. The values of any foreign securities held by a fund are converted into U.S. dollars using an exchange rate obtained from an independent third party as of the close of regular trading on the NYSE. The values of any mutual fund shares held by a fund are based on the NAVs of the shares. The values of any ETF or closed-end fund shares held by a fund are based on the market value of the shares.

When a fund determines that market quotations either are not readily available or do not accurately reflect the value of a security, the security is priced at its fair value (the amount that the owner might reasonably expect to receive upon the current sale of the security). A fund also will use fair-value pricing if the value of a security it holds has been materially affected by events occurring before the fund’s pricing time but after the close of the principal exchange or market on which the security is traded. This most commonly occurs with foreign securities, which may trade on foreign exchanges that close many hours before the fund’s pricing time. Intervening events might be company-specific (e.g., earnings report, merger announcement) or country-specific or regional/global (e.g., natural disaster, economic or political news, act of terrorism, interest rate change). Intervening events include price movements in U.S. markets that exceed a specified threshold or that are otherwise deemed to affect the value of foreign securities. Fair-value pricing may be used for domestic securities—for example, if (1) trading in a security is halted and does not resume before the fund’s pricing time or a security does not trade in the course of a day and (2) the fund holds enough of the security that its price could affect the NAV.

Fair-value prices are determined by Vanguard according to procedures adopted by the board of trustees. When fair-value pricing is employed, the prices of securities used by a fund to calculate the NAV may differ from quoted or published prices for the same securities.

Vanguard fund share prices are published daily on our website at vanguard.com/prices.

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Financial Highlights

The following financial highlights table is intended to help you understand the Institutional Shares‘ financial performance for the periods shown, and certain information reflects financial results for a single Institutional Share. The total returns in the table represent the rate that an investor would have earned or lost each period on an investment in the Institutional Shares (assuming reinvestment of all distributions). This information has been obtained from the financial statements audited by PricewaterhouseCoopers LLP, an independent registered public accounting firm, whose report—along with the Fund’s financial statements—is included in the Fund’s most recent annual report to shareholders. You may obtain a free copy of the latest annual or semiannual report by visiting vanguard.com or by contacting Vanguard by telephone or mail.

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Investing With Vanguard

This section of the prospectus explains the basics of doing business with Vanguard. Vanguard fund shares can be held directly with Vanguard or indirectly through an intermediary, such as a bank, a broker, or an investment advisor. If you hold Vanguard fund shares directly with Vanguard, you should carefully read each topic within this section that pertains to your relationship with Vanguard. If you hold Vanguard fund shares indirectly through an intermediary (including shares held through a Vanguard brokerage account), please see Investing With Vanguard Through Other Firms, and also refer to your account agreement with the intermediary for information about transacting in that account. Vanguard reserves the right to change the following policies without notice. Please call or check online for current information. See

Contacting Vanguard.

For Vanguard fund shares held directly with Vanguard, each fund you hold in an account is a separate “fund account.” For example, if you hold three funds in a nonretirement account titled in your own name, two funds in a nonretirement account titled jointly with your spouse, and one fund in an individual retirement account, you have six fund accounts—and this is true even if you hold the same fund in multiple accounts. Note that each reference to “you” in this prospectus applies to any one or more registered account owners or persons authorized to transact on your account.

Purchasing Shares

Vanguard reserves the right, without notice, to increase or decrease the minimum amount required to open, convert shares to, or maintain a fund account or to add to an existing fund account.

Investment minimums may differ for certain categories of investors.

Account Minimums for Institutional Shares To open and maintain an account. $5 million.

Certain Vanguard institutional clients may meet the minimum investment amount by aggregating separate accounts within the same Fund. This aggregation policy does not apply to financial intermediaries.

Vanguard may charge additional recordkeeping fees for institutional clients whose accounts are recordkept by Vanguard. Please contact your Vanguard representative to determine whether additional recordkeeping fees apply to your account.

To add to an existing account. Generally $1.

How to Initiate a Purchase Request

Be sure to check Exchanging Shares, Frequent-Trading Limitations, and Other Rules You Should Know before placing your purchase request.

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Online. You may open certain types of accounts, request a purchase of shares, and request an exchange through our website or our mobile application if you are registered for online access.

By telephone. You may call Vanguard to begin the account registration process or request that the account-opening forms be sent to you. You may also call Vanguard to request a purchase of shares in your account or to request an exchange. See

Contacting Vanguard.

By mail. You may send Vanguard your account registration form and check to open a new fund account. To add to an existing fund account, you may send your check with an Invest-by-Mail form (from a transaction confirmation or your account statement), with a deposit slip (available online), or with a written request. You may also send a written request to Vanguard to make an exchange. For a list of Vanguard addresses, see Contacting Vanguard.

How to Pay for a Purchase

By electronic bank transfer. You may purchase shares of a Vanguard fund through an electronic transfer of money from a bank account. To establish the electronic bank transfer service on an account, you must designate the bank account online, complete a special form, or fill out the appropriate section of your account registration form. After the service is set up on your account, you can purchase shares by electronic bank transfer on a regular schedule (Automatic Investment Plan) or upon request. Your purchase request can be initiated online (if you are registered for online access), by telephone, or by mail.

By wire. Wiring instructions vary for different types of purchases. Please call Vanguard for instructions and policies on purchasing shares by wire. See Contacting Vanguard.

By check. You may make initial or additional purchases to your fund account by sending a check or by utilizing our mobile application if you are registered for online access. Also see How to Initiate a Purchase Request. Make your check payable to Vanguard and include the appropriate fund number (Vanguard—734).

By exchange. You may purchase shares of a Vanguard fund using the proceeds from the simultaneous redemption of shares of another Vanguard fund. You may initiate an exchange online (if you are registered for online access), by telephone, or by mail. See

Exchanging Shares.

Trade Date

The trade date for any purchase request received in good order will depend on the day and time Vanguard receives your request, the manner in which you are paying, and the type of fund you are purchasing. Your purchase will be executed using the net

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asset value (NAV) as calculated on the trade date. NAVs are calculated only on days that the New York Stock Exchange (NYSE) is open for trading (a business day).

For purchases by check into all funds other than money market funds and for purchases by exchange, wire, or electronic bank transfer (not using an Automatic Investment Plan) into all funds: If the purchase request is received by Vanguard on a business day before the close of regular trading on the NYSE (generally 4 p.m., Eastern time), the trade date for the purchase will be the same day. If the purchase request is received on a business day after the close of regular trading on the NYSE, or on a nonbusiness day, the trade date for the purchase will be the next business day.

For purchases by check into money market funds: If the purchase request is received by Vanguard on a business day before the close of regular trading on the NYSE (generally 4 p.m., Eastern time), the trade date for the purchase will be the next business day. If the purchase request is received on a business day after the close of regular trading on the NYSE, or on a nonbusiness day, the trade date for the purchase will be the second business day following the day Vanguard receives the purchase request. Because money market instruments must be purchased with federal funds and it takes a money market mutual fund one business day to convert check proceeds into federal funds, the trade date for the purchase will be one business day later than for other funds.

For purchases by electronic bank transfer using an Automatic Investment Plan: Your trade date generally will be the date you selected for withdrawal of funds from your designated bank account. Your bank account generally will be debited on the business day after your trade date. If the date you selected for withdrawal of funds from your bank account falls on a weekend, holiday, or other nonbusiness day, your trade date generally will be the previous business day. For retirement accounts, if the date you selected for withdrawal of funds from your designated bank account falls on the last business day of the year, your trade date will be the first business day of the following year. Please note that if you select the first of the month for automated withdrawals from your designated bank account, trades designated for January 1 will receive the next business day’s trade date.

If your purchase request is not accurate and complete, it may be rejected. See Other Rules You Should Know—Good Order.

For further information about purchase transactions, consult our website at vanguard.com or see Contacting Vanguard.

Other Purchase Rules You Should Know

Check purchases. All purchase checks must be written in U.S. dollars and must be drawn on a U.S. bank. Vanguard does not accept cash, traveler’s checks, or money

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orders. In addition, Vanguard may refuse “starter checks” and checks that are not made payable to Vanguard.

New accounts. We are required by law to obtain from you certain personal information that we will use to verify your identity. If you do not provide the information, we may not be able to open your account. If we are unable to verify your identity, Vanguard reserves the right, without notice, to close your account or take such other steps as we deem reasonable. Certain types of accounts may require additional documentation.

Refused or rejected purchase requests. Vanguard reserves the right to stop selling fund shares or to reject any purchase request at any time and without notice, including, but not limited to, purchases requested by exchange from another Vanguard fund. This also includes the right to reject any purchase request because the investor has a history of frequent trading or because the purchase may negatively affect a fund’s operation or performance.

Large purchases. Call Vanguard before attempting to invest a large dollar amount.

No cancellations. Vanguard will not accept your request to cancel any purchase request once processing has begun. Please be careful when placing a purchase request.

Converting Shares

When a conversion occurs, you receive shares of one class in place of shares of another class of the same fund. At the time of conversion, the dollar value of the “new” shares you receive equals the dollar value of the “old” shares that were converted. In other words, the conversion has no effect on the value of your investment in the fund at the time of the conversion. However, the number of shares you own after the conversion may be greater than or less than the number of shares you owned before the conversion, depending on the NAVs of the two share classes.

Vanguard will not accept your request to cancel any self-directed conversion request once processing has begun. Please be careful when placing a conversion request.

A conversion between share classes of the same fund is a nontaxable event.

Trade Date

The trade date for any conversion request received in good order will depend on the day and time Vanguard receives your request. Your conversion will be executed using the NAVs of the different share classes on the trade date. NAVs are calculated only on days that the NYSE is open for trading (a business day).

For a conversion request received by Vanguard on a business day before the close of regular trading on the NYSE (generally 4 p.m., Eastern time), the trade date will be the same day. For a conversion request received on a business day after the close of

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regular trading on the NYSE, or on a nonbusiness day, the trade date will be the next business day. See Other Rules You Should Know.

Conversions to Institutional Shares

You are eligible for a self-directed conversion from Investor Shares to Institutional Shares of the Fund, provided that your account meets all Institutional Shares’ eligibility requirements. You may request a conversion through our website (if you are registered for online access), or you may contact Vanguard by telephone or by mail to request this transaction. Accounts that qualify for Institutional Shares will not be automatically converted.

Mandatory Conversions to Investor Shares

If an account no longer meets the balance requirements for Institutional Shares, Vanguard may automatically convert the shares in the account to Investor Shares. A decline in the account balance because of market movement may result in such a conversion. Vanguard will notify the investor in writing before any mandatory conversion occurs.

Redeeming Shares

How to Initiate a Redemption Request

Be sure to check Exchanging Shares, Frequent-Trading Limitations, and Other Rules You Should Know before placing your redemption request.

Online. You may request a redemption of shares or request an exchange through our website or our mobile application if you are registered for online access.

By telephone. You may call Vanguard to request a redemption of shares or an exchange. See Contacting Vanguard.

By mail. You may send a written request to Vanguard to redeem from a fund account or to make an exchange. See Contacting Vanguard.

How to Receive Redemption Proceeds

By electronic bank transfer. You may have the proceeds of a fund redemption sent directly to a designated bank account. To establish the electronic bank transfer service on an account, you must designate a bank account online, complete a special form, or fill out the appropriate section of your account registration form. After the service is set up on your account, you can redeem shares by electronic bank transfer on a regular schedule (Automatic Withdrawal Plan) or upon request. Your redemption request can be initiated online (if you are registered for online access), by telephone, or by mail.

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By wire. To receive your proceeds by wire, you may instruct Vanguard to wire your redemption proceeds ($100 minimum) to a previously designated bank account. To establish the wire redemption service, you generally must designate a bank account online, complete a special form, or fill out the appropriate section of your account registration form.

By exchange. You may have the proceeds of a Vanguard fund redemption invested directly in shares of another Vanguard fund. You may initiate an exchange online (if you are registered for online access), by telephone, or by mail. See Exchanging Shares.

By check. If you have not chosen another redemption method, Vanguard will mail you a redemption check, generally payable to all registered account owners, normally within two business days of your trade date, and generally to the address of record.

Trade Date

The trade date for any redemption request received in good order will depend on the day and time Vanguard receives your request and the manner in which you are redeeming. Your redemption will be executed using the NAV as calculated on the trade date. NAVs are calculated only on days that the NYSE is open for trading (a business day).

For redemptions by check, exchange, or wire: If the redemption request is received by Vanguard on a business day before the close of regular trading on the NYSE (generally 4 p.m., Eastern time), the trade date will be the same day. If the redemption request is received on a business day after the close of regular trading on the NYSE, or on a nonbusiness day, the trade date will be the next business day.

• Note on timing of wire redemptions from money market funds: For telephone requests received by Vanguard on a business day before 10:45 a.m., Eastern time (2 p.m., Eastern time, for Vanguard Prime Money Market Fund), the redemption proceeds generally will leave Vanguard by the close of business the same day. For telephone requests received by Vanguard on a business day after those cut-off times, or on a nonbusiness day, and for all requests other than by telephone, the redemption proceeds generally will leave Vanguard by the close of business on the next business day.

• Note on timing of wire redemptions from all other funds: For requests received by Vanguard on a business day before the close of regular trading on the NYSE (generally 4 p.m., Eastern time), the redemption proceeds generally will leave Vanguard by the close of business on the next business day. For requests received by Vanguard on a business day after the close of regular trading on the NYSE, or on a nonbusiness day, the redemption proceeds generally will leave Vanguard by the close of business on the second business day after Vanguard receives the request.

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For redemptions by electronic bank transfer using an Automatic Withdrawal Plan: Your trade date generally will be the date you selected for withdrawal of funds (redemption of shares) from your Vanguard account. Proceeds of redeemed shares generally will be credited to your designated bank account two business days after your trade date. If the date you selected for withdrawal of funds from your Vanguard account falls on a weekend, holiday, or other nonbusiness day, your trade date generally will be the previous business day. For retirement accounts, if the date you selected for withdrawal of funds from your Vanguard account falls on the last day of the year and if that date is a holiday, your trade date will be the first business day of the following year. Please note that if you designate the first of the month for automated withdrawals, trades designated for January 1 will receive the next business day’s trade date.

For redemptions by electronic bank transfer not using an Automatic Withdrawal Plan: If the redemption request is received by Vanguard on a business day before the close of regular trading on the NYSE (generally 4 p.m., Eastern time), the trade date will be the same day. If the redemption request is received on a business day after the close of regular trading on the NYSE, or on a nonbusiness day, the trade date will be the next business day.

If your redemption request is not accurate and complete, it may be rejected. If we are unable to send your redemption proceeds by wire or electronic bank transfer because the receiving institution rejects the transfer, Vanguard will make additional efforts to complete your transaction. If Vanguard is still unable to complete the transaction, we may send the proceeds of the redemption to you by check, generally payable to all registered account owners, or use your proceeds to purchase new shares of the fund from which you sold shares for the purpose of the wire or electronic bank transfer transaction. See Other Rules You Should Know—Good Order.

For further information about redemption transactions, consult our website at vanguard.com or see Contacting Vanguard.

Other Redemption Rules You Should Know

Documentation for certain accounts. Special documentation may be required to redeem from certain types of accounts, such as trust, corporate, nonprofit, or retirement accounts. Please call us before attempting to redeem from these types of accounts.

Potentially disruptive redemptions. Vanguard reserves the right to pay all or part of a redemption in kind—that is, in the form of securities—if we reasonably believe that a cash redemption would negatively affect the fund’s operation or performance or that the shareholder may be engaged in market-timing or frequent trading. Under these circumstances, Vanguard also reserves the right to delay payment of the redemption

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proceeds for up to seven calendar days. By calling us before you attempt to redeem a large dollar amount, you may avoid in-kind or delayed payment of your redemption. Please see Frequent-Trading Limitations for information about Vanguard’s policies to limit frequent trading.

Recently purchased shares. Although you can redeem shares at any time, proceeds may not be made available to you until the fund collects payment for your purchase. This may take up to seven calendar days for shares purchased by check or by electronic bank transfer. If you have written a check on a fund with checkwriting privileges, that check may be rejected if your fund account does not have a sufficient available balance.

Address change. If you change your address online or by telephone, there may be up to a 14-day restriction on your ability to request check redemptions online and by telephone. You can request a redemption in writing at any time. Confirmations of address changes are sent to both the old and new addresses.

Payment to a different person or address. At your request, we can make your redemption check payable, or wire your redemption proceeds, to a different person or send it to a different address. However, this generally requires the written consent of all registered account owners and may require additional documentation, such as a signature guarantee or a notarized signature. You may obtain a signature guarantee from some commercial or savings banks, credit unions, trust companies, or member firms of a U.S. stock exchange.

No cancellations. Vanguard will not accept your request to cancel any redemption request once processing has begun. Please be careful when placing a redemption request.

Emergency circumstances. Vanguard funds can postpone payment of redemption proceeds for up to seven calendar days. In addition, Vanguard funds can suspend redemptions and/or postpone payments of redemption proceeds beyond seven calendar days at times when the NYSE is closed or during emergency circumstances, as determined by the SEC.

Exchanging Shares

An exchange occurs when you use the proceeds from the redemption of shares of one Vanguard fund to simultaneously purchase shares of a different Vanguard fund. You can make exchange requests online (if you are registered for online access), by telephone, or by mail. See Purchasing Shares and Redeeming Shares.

If the NYSE is open for regular trading (generally until 4 p.m., Eastern time, on a business day) at the time an exchange request is received in good order, the trade date generally will be the same day. See Other Rules You Should Know—Good Order for additional information on all transaction requests.

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Vanguard will not accept your request to cancel any exchange request once processing has begun. Please be careful when placing an exchange request.

Please note that Vanguard reserves the right, without notice, to revise or terminate the exchange privilege, limit the amount of any exchange, or reject an exchange, at any time, for any reason. See Frequent-Trading Limitations for additional restrictions on exchanges.

Frequent-Trading Limitations

Because excessive transactions can disrupt management of a fund and increase the fund’s costs for all shareholders, the board of trustees of each Vanguard fund places certain limits on frequent trading in the funds. Each Vanguard fund (other than money market funds and short-term bond funds, but including Vanguard Short-Term Inflation-Protected Securities Index Fund) limits an investor’s purchases or exchanges into a fund account for 30 calendar days (60 calendar days for participants in employer-sponsored defined contribution plans recordkept directly by Vanguard) after the investor has redeemed or exchanged out of that fund account. ETF Shares are not subject to these frequent-trading limits.

For Vanguard Retirement Investment Program pooled plans, the limitations apply to exchanges made online or by telephone.

These frequent-trading limitations do not apply to the following:

• Purchases of shares with reinvested dividend or capital gains distributions.

• Transactions through Vanguard’s Automatic Investment Plan, Automatic Exchange Service, Direct Deposit Service, Automatic Withdrawal Plan, Required Minimum Distribution Service, and Vanguard Small Business Online^®.

• Discretionary transactions through Vanguard Asset Management Services, Vanguard Personal Advisor Services, and Vanguard Institutional Advisory Services^®.

• Redemptions of shares to pay fund or account fees.

• Redemptions of shares to remove excess shareholder contributions to certain types of retirement accounts (including, but not limited to, IRAs, certain Individual 403(b)(7) Custodial Accounts, and Vanguard Individual 401(k) Plans).

• Transaction requests submitted by mail to Vanguard from shareholders who hold their accounts directly with Vanguard or through a Vanguard brokerage account. (Transaction requests submitted by fax, if otherwise permitted, are subject to the limitations.)

• Transfers and reregistrations of shares within the same fund.

• Purchases of shares by asset transfer or direct rollover.

• Conversions of shares from one share class to another in the same fund.

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• Checkwriting redemptions.

• Section 529 college savings plans.

• Certain approved institutional portfolios and asset allocation programs, as well as trades made by funds or trusts managed by Vanguard or its affiliates that invest in other Vanguard funds. (Please note that shareholders of Vanguard’s funds of funds are subject to the limitations.)

For participants in employer-sponsored defined contribution plans,* the frequent-trading limitations do not apply to:

• Purchases of shares with participant payroll or employer contributions or loan repayments.

• Purchases of shares with reinvested dividend or capital gains distributions.

• Distributions, loans, and in-service withdrawals from a plan.

• Redemptions of shares as part of a plan termination or at the direction of the plan.

• Transactions executed through the Vanguard Managed Account Program.

• Redemptions of shares to pay fund or account fees.

• Share or asset transfers or rollovers.

• Reregistrations of shares.

• Conversions of shares from one share class to another in the same fund.

• Exchange requests submitted by written request to Vanguard. (Exchange requests submitted by fax, if otherwise permitted, are subject to the limitations.)

* The following Vanguard fund accounts are subject to the frequent-trading limitations: SEP-IRAs, SIMPLE IRAs, certain Individual 403(b)(7) Custodial Accounts, and Vanguard Individual 401(k) Plans.

Accounts Held by Institutions (Other Than Defined Contribution Plans)

Vanguard will systematically monitor for frequent trading in institutional clients’ accounts. If we detect suspicious trading activity, we will investigate and take appropriate action, which may include applying to a client’s accounts the 30-day policy previously described, prohibiting a client’s purchases of fund shares, and/or revoking the client’s exchange privilege.

Accounts Held by Intermediaries

When intermediaries establish accounts in Vanguard funds for the benefit of their clients, we cannot always monitor the trading activity of the individual clients. However, we review trading activity at the intermediary (omnibus) level, and if we detect suspicious activity, we will investigate and take appropriate action. If necessary, Vanguard may prohibit additional purchases of fund shares by an

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intermediary, including for the benefit of certain of the intermediary’s clients. Intermediaries also may monitor their clients’ trading activities with respect to Vanguard funds.

For those Vanguard funds that charge purchase and/or redemption fees, intermediaries will be asked to assess these fees on client accounts and remit these fees to the funds. The application of purchase and redemption fees and frequent-trading limitations may vary among intermediaries. There are no assurances that Vanguard will successfully identify all intermediaries or that intermediaries will properly assess purchase and redemption fees or administer frequent-trading limitations. If you invest with Vanguard through an intermediary, please read that firm’s materials carefully to learn of any other rules or fees that may apply.

Other Rules You Should Know

Prospectus and Shareholder Report Mailings

When two or more shareholders have the same last name and address, just one summary prospectus (or prospectus) and/or shareholder report may be sent in an attempt to eliminate the unnecessary expense of duplicate mailings. You may request individual prospectuses and reports by contacting our Client Services Department in writing, by telephone, or online. See Contacting Vanguard.

Vanguard.com

Registration. If you are a registered user of vanguard.com, you can review your account holdings; buy, sell, or exchange shares of most Vanguard funds; and perform most other transactions through our website. You must register for this service online.

Electronic delivery. Vanguard can deliver your account statements, transaction confirmations, prospectuses, tax forms, and shareholder reports electronically. If you are a registered user of vanguard.com, you can consent to the electronic delivery of these documents by logging on and changing your mailing preferences under “Account Maintenance.” You can revoke your electronic consent at any time through our website, and we will begin to send paper copies of these documents within 30 days of receiving your revocation.

Telephone Transactions

Automatic. When we set up your account, we will automatically enable you to do business with us by telephone, unless you instruct us otherwise in writing.

Tele-Account^®. To obtain fund and account information through Vanguard’s automated telephone service, you must first establish a Personal Identification Number (PIN) by calling Tele-Account at 800-662-6273.

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Proof of a caller’s authority. We reserve the right to refuse a telephone request if the caller is unable to provide the requested information or if we reasonably believe that the caller is not an individual authorized to act on the account. Before we allow a caller to act on an account, we may request the following information:

• Authorization to act on the account (as the account owner or by legal documentation or other means).

• Account registration and address.

• Fund name and account number, if applicable.

• Other information relating to the caller, the account owner, or the account.

Good Order

We reserve the right to reject any transaction instructions that are not in “good order.” Good order generally means that your instructions:

• Are provided by the person(s) authorized in accordance with Vanguard’s policies and procedures to access the account and request transactions.

• Include the fund name and account number.

• Include the amount of the transaction (stated in dollars, shares, or percentage).

Written instructions also must generally include:

• An original signature and date from the authorized person(s).

• Signature guarantees or notarized signatures, if required for the type of transaction.

(Call Vanguard for specific requirements.)

• Any supporting documentation that may be required.

Written instructions are acceptable when a Vanguard form is not applicable. The requirements vary among types of accounts and transactions. For more information, consult our website at vanguard.com or see Contacting Vanguard.

Vanguard reserves the right, without notice, to revise the requirements for good order.

Future Trade-Date Requests

Vanguard does not accept requests to hold a purchase, conversion, redemption, or exchange transaction for a future date. All such requests will receive trade dates as previously described in Purchasing Shares, Converting Shares, Redeeming Shares, and

Exchanging Shares. Vanguard reserves the right to return future-dated purchase checks.

Accounts With More Than One Owner

If an account has more than one owner or authorized person, Vanguard generally will accept instructions from any one owner or authorized person.

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Responsibility for Fraud

Vanguard will not be responsible for any account losses because of fraud if we reasonably believe that the person transacting business on an account is authorized to do so. Please take precautions to protect yourself from fraud. Keep your account information private, and immediately review any account statements or other information that we provide to you. It is important that you contact Vanguard immediately about any transactions or changes to your account that you believe to be unauthorized.

Uncashed Checks

Please cash your distribution or redemption checks promptly. Vanguard will not pay interest on uncashed checks. Vanguard may be required to transfer assets related to uncashed checks to a state under the state’s abandoned property law.

Dormant Accounts

If your account has no activity in it for a period of time, Vanguard may be required to transfer it to a state under the state’s abandoned property law.

Unusual Circumstances

If you experience difficulty contacting Vanguard online or by telephone, you can send us your transaction request by regular or express mail. See Contacting Vanguard for addresses.

Investing With Vanguard Through Other Firms

You may purchase or sell shares of most Vanguard funds through a financial intermediary, such as a bank, a broker, or an investment advisor. Please consult your financial intermediary to determine which, if any, shares are available through that firm and to learn about other rules that may apply. Your financial intermediary can provide you with account information and any required tax forms.

Please see Frequent-Trading Limitations—Accounts Held by Intermediaries for information about the assessment of any purchase or redemption fees and the monitoring of frequent trading for accounts held by intermediaries.

Account Service Fee

Vanguard charges a $20 account service fee on fund accounts that have a balance below $10,000 for any reason, including market fluctuation. The account service fee applies to both retirement and nonretirement fund accounts and will be assessed on fund accounts in all Vanguard funds, regardless of the account minimum. The fee, which will be collected by redeeming fund shares in the amount of $20, will be deducted from a fund account only once per calendar year.

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If you register on vanguard.com and elect to receive electronic delivery of statements, reports, and other materials for all of your fund accounts, the account service fee for balances below $10,000 will not be charged, so long as that election remains in effect.

The account service fee also does not apply to the following:

• Money market sweep accounts owned in connection with a Vanguard Brokerage Services^® account.

• Accounts held through intermediaries.

• Accounts held by institutional clients.

• Accounts held by Voyager, Voyager Select, Flagship, and Flagship Select clients.

Eligibility is based on total household assets held at Vanguard, with a minimum of $50,000 to qualify for Vanguard Voyager Services^®, $500,000 for Vanguard Voyager Select Services^®, $1 million for Vanguard Flagship Services^®, and $10 million for Vanguard Flagship Select Services^™. Vanguard determines eligibility by aggregating assets of all qualifying accounts held by the investor and immediate family members who reside at the same address. Aggregate assets include investments in Vanguard mutual funds, Vanguard ETFs^®, certain annuities through Vanguard, the Vanguard 529 Plan, and certain small-business accounts. Assets in employer-sponsored retirement plans for which Vanguard provides recordkeeping services may be included in determining eligibility if the investor also has a personal account holding Vanguard mutual funds. Note that assets held in a Vanguard Brokerage Services account (other than Vanguard funds, including Vanguard ETFs) are not included when determining a household’s eligibility.

• Participant accounts in employer-sponsored defined contribution plans.* Please consult your enrollment materials for the rules that apply to your account.

• Section 529 college savings plans.

* The following Vanguard fund accounts have alternative fee structures: SIMPLE IRAs, certain Individual 403(b)(7) Custodial Accounts, Vanguard Retirement Investment Program pooled plans, and Vanguard Individual 401(k) Plans.

Low-Balance Accounts

The Fund reserves the right to convert an investor’s Institutional Shares to Investor Shares if the fund account balance falls below the account minimum for any reason, including market fluctuation. Any such conversion will be preceded by written notice to the investor.

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Right to Change Policies

In addition to the rights expressly stated elsewhere in this prospectus, Vanguard reserves the right, without notice, to (1) alter, add, or discontinue any conditions of purchase (including eligibility requirements), redemption, exchange, conversion, service, or privilege at any time; (2) accept initial purchases by telephone; (3) freeze any account and/or suspend account services if Vanguard has received reasonable notice of a dispute regarding the assets in an account, including notice of a dispute between the registered or beneficial account owners, or if Vanguard reasonably believes a fraudulent transaction may occur or has occurred; (4) temporarily freeze any account and/or suspend account services upon initial notification to Vanguard of the death of the shareholder until Vanguard receives required documentation in good order; (5) alter, impose, discontinue, or waive any purchase fee, redemption fee, account service fee, or other fees charged to a group of shareholders; and (6) redeem an account or suspend account privileges, without the owner’s permission to do so, in cases of threatening conduct or activity Vanguard believes to be suspicious, fraudulent, or illegal. Changes may affect any or all investors. These actions will be taken when, at the sole discretion of Vanguard management, Vanguard reasonably believes they are deemed to be in the best interest of a fund.

Share Classes

Vanguard reserves the right, without notice, to change the eligibility requirements of its share classes, including the types of clients who are eligible to purchase each share class.

Fund and Account Updates

Confirmation Statements

We will send (or provide through our website, whichever you prefer) a confirmation of your trade date and the amount of your transaction when you buy, sell, exchange, or convert shares. However, we will not send confirmations reflecting only checkwriting redemptions or the reinvestment of dividend or capital gains distributions. For any month in which you had a checkwriting redemption, a Checkwriting Activity Statement will be sent to you itemizing the checkwriting redemptions for that month. Promptly review each confirmation statement that we provide to you. It is important that you contact Vanguard immediately with any questions you may have about any transaction reflected on a confirmation statement, or Vanguard will consider the transaction properly processed.

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Portfolio Summaries

We will send (or provide through our website, whichever you prefer) quarterly portfolio summaries to help you keep track of your accounts throughout the year. If you prefer, you may request to receive monthly portfolio summaries. Each summary shows the market value of your account at the close of the statement period, as well as all distributions, purchases, redemptions, exchanges, transfers, and conversions for the current calendar quarter (or month). Promptly review each summary that we provide to you. It is important that you contact Vanguard immediately with any questions you may have about any transaction reflected on the summary, or Vanguard will consider the transaction properly processed.

Tax Information Statements

For most accounts, we are required to provide annual tax forms to assist you in preparing your income tax returns. We will send (or provide through our website, whichever you prefer) tax forms for each calendar year early in the following year. Registered users of vanguard.com can also view these forms through our website. Vanguard may also provide you with additional tax-related documentation. For more information, consult our website at vanguard.com or see Contacting Vanguard.

Annual and Semiannual Reports

We will send (or provide through our website, whichever you prefer) reports about Vanguard Market Neutral Fund twice a year, in February and August. These reports include overviews of the financial markets and provide the following specific Fund information:

• Performance assessments and comparisons with industry benchmarks.

• Reports from the advisor.

• Financial statements with listings of Fund holdings.

Portfolio Holdings

Please consult the Fund’s Statement of Additional Information or our website for a description of the policies and procedures that govern disclosure of the Fund’s portfolio holdings.

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Vanguard Addresses

Please be sure to use the correct address. Use of an incorrect address could delay the processing of your transaction.

CFA^® is a registered trademark owned by CFA Institute.

Morningstar data © 2016 Morningstar, Inc. All Rights Reserved. The information contained herein: (1) is proprietary to Morningstar and/or its content providers; (2) may not be copied or distributed; and (3) is not warranted to be accurate, complete or timely. Neither Morningstar nor its content providers are responsible for any damages or losses arising from any use of this information. Past performance is no guarantee of future results.

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Glossary of Investment Terms

Borrowing Expense on Securities Sold Short. A fee charged by a fund’s broker when a fund sells a stock short. This fee is calculated on a daily basis, based upon the market value of the stock sold short and a variable rate that is dependent upon the availability of the stock.

Capital Gains Distribution. Payment to mutual fund shareholders of gains realized on securities that a fund has sold at a profit, minus any realized losses.

Cash Equivalent Investments. Cash deposits, short-term bank deposits, and money market instruments that include U.S. Treasury bills and notes, bank certificates of deposit (CDs), repurchase agreements, commercial paper, and banker’s acceptances.

Citigroup 3-Month U.S. Treasury Bill Index. An index that measures performance of short-term U.S. government debt securities.

Common Stock. A security representing ownership rights in a corporation.

Dividend Distribution. Payment to mutual fund shareholders of income from interest or dividends generated by a fund’s investments.

Dividend Expense on Securities Sold Short. The amount of money that a fund is required to pay to a lender of stock that the fund has sold short when a dividend has been declared on the stock.

Expense Ratio. A fund’s total annual operating expenses expressed as a percentage of the fund’s average net assets. The expense ratio includes management and administrative expenses, but it does not include the transaction costs of buying and selling portfolio securities.

Inception Date. The date on which the assets of a fund (or one of its share classes) are first invested in accordance with the fund’s investment objective. For funds with a subscription period, the inception date is the day after that period ends. Investment performance is generally measured from the inception date.

Mutual Fund. An investment company that pools the money of many people and invests it in a variety of securities in an effort to achieve a specific objective over time.

Quantitative Process. An assessment of specific measurable factors, such as cost of capital; value of assets; and projections of sales, costs, earnings, and profits. The use of a quantitative process provides a systematic approach to investment decisions and portfolios.

Securities. Stocks, bonds, money market instruments, and other investments.

Short Sale. A transaction in which a fund sells a stock it does not own and then borrows the stock from a lender in order to settle the transaction. A fund will engage in short sales when its advisor believes that the price of the stock will decline or underperform.

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Total Return. A percentage change, over a specified time period, in a mutual fund’s net asset value, assuming the reinvestment of all distributions of dividends and capital gains.

Volatility. The fluctuations in value of a mutual fund or other security. The greater a fund’s volatility, the wider the fluctuations in its returns.

Yield. Income (interest or dividends) earned by an investment, expressed as a percentage of the investment’s price.

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Institutional Division P.O. Box 2900 Valley Forge, PA 19482-2900

© 2016 The Vanguard Group, Inc. All rights reserved. Vanguard Marketing Corporation, Distributor.

I 734 042016

PART B

VANGUARD^® MONTGOMERY FUNDS

STATEMENT OF ADDITIONAL INFORMATION

April 28, 2016

This Statement of Additional Information is not a prospectus but should be read in conjunction with the Fund’s current prospectus (dated April 28, 2016). To obtain, without charge, a prospectus or the most recent Annual Report to Shareholders, which contains the Fund’s financial statements as hereby incorporated by reference, please contact The Vanguard Group, Inc. (Vanguard).

The Trust has the ability to offer additional funds or classes of shares. There is no limit on the number of full and fractional shares that may be issued for a single fund or class of shares.

Organization

The Trust was organized as a Delaware statutory trust in 2007. The Trust is registered with the United States Securities and Exchange Commission (SEC) under the Investment Company Act of 1940 (the 1940 Act) as an open-end management investment company. Vanguard Market Neutral Fund (the Fund) is classified as diversified within the meaning of the 1940 Act.

Vanguard Market Neutral Fund was formed in connection with the reorganization of a previously existing fund, known as Laudus Rosenberg U.S. Large/Mid Capitalization Long/Short Equity Fund (Laudus Fund), which was previously sponsored and managed by Charles Schwab Investment Management, Inc., and sub-advised by AXA Rosenberg Investment Management LLC. On November 30, 2007, Vanguard Market Neutral Fund acquired the assets and liabilities of the Laudus Fund in a tax-free reorganization, while maintaining a substantially similar investment objective and substantially similar investment strategies and policies.

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Service Providers

Custodian. Brown Brothers Harriman & Co., 50 Post Office Square, Boston, MA 02110-1548, serves as the Fund‘s custodian. The custodian is responsible for maintaining the Fund‘s assets, keeping all necessary accounts and records of Fund assets, and appointing any foreign subcustodians or foreign securities depositories.

Independent Registered Public Accounting Firm. PricewaterhouseCoopers LLP, Two Commerce Square, Suite 1800, 2001 Market Street, Philadelphia, PA 19103-7042, serves as the Fund‘s independent registered public accounting firm. The independent registered public accounting firm audits the Fund‘s annual financial statements and provides other related services.

Transfer and Dividend-Paying Agent. The Fund‘s transfer agent and dividend-paying agent is Vanguard, P.O. Box 2600, Valley Forge, PA 19482.

Characteristics of the Fund‘s Shares

Restrictions on Holding or Disposing of Shares. There are no restrictions on the right of shareholders to retain or dispose of the Fund’s shares, other than those described in the Fund’s current prospectus and elsewhere in this Statement of Additional Information. The Fund or class may be terminated by reorganization into another mutual fund or class or by liquidation and distribution of the assets of the Fund or class. Unless terminated by reorganization or liquidation, the Fund and share classes will continue indefinitely.

Shareholder Liability. The Trust is organized under Delaware law, which provides that shareholders of a statutory trust are entitled to the same limitations of personal liability as shareholders of a corporation organized under Delaware law. This means that a shareholder of the Fund generally will not be personally liable for payment of the Fund’s debts. Some state courts, however, may not apply Delaware law on this point. We believe that the possibility of such a situation arising is remote.

Dividend Rights. The shareholders of each class of the Fund are entitled to receive any dividends or other distributions declared by the Fund for each such class. No shares of the Fund have priority or preference over any other shares of the Fund with respect to distributions. Distributions will be made from the assets of the Fund and will be paid ratably to all shareholders of a particular class according to the number of shares of the class held by shareholders on the record date. The amount of dividends per share may vary between separate share classes of the Fund based upon differences in the net asset values of the different classes and differences in the way that expenses are allocated between share classes pursuant to a multiple class plan approved by the Fund’s board of trustees.

Voting Rights. Shareholders are entitled to vote on a matter if (1) the matter concerns an amendment to the Declaration of Trust that would adversely affect to a material degree the rights and preferences of the shares of the Fund or any class; (2) the trustees determine that it is necessary or desirable to obtain a shareholder vote; (3) a merger or consolidation, share conversion, share exchange, or sale of assets is proposed and a shareholder vote is required by the 1940 Act to approve the transaction; or (4) a shareholder vote is required under the 1940 Act. The 1940 Act requires a shareholder vote under various circumstances, including to elect or remove trustees upon the written request of shareholders representing 10% or more of the Fund’s net assets, to change any fundamental policy of the Fund (please see Fundamental Policies), and to enter into certain merger transactions. Unless otherwise required by applicable law, shareholders of the Fund receive one vote for each dollar of net asset value owned on the record date and a fractional vote for each fractional dollar of net asset value owned on the record date. However, only the shares of the Fund or class affected by a particular matter are entitled to vote on that matter. In addition, each class has exclusive voting rights on any matter submitted to shareholders that relates solely to that class, and each class has separate voting rights on any matter submitted to shareholders in which the interests of one class differ from the interests of another. Voting rights are noncumulative and cannot be modified without a majority vote by the shareholders.

Liquidation Rights. In the event that the Fund is liquidated, shareholders will be entitled to receive a pro rata share of the Fund’s net assets. In the event that a class of shares is liquidated, shareholders of that class will be entitled to receive a pro rata share of the Fund’s net assets that are allocated to that class. Shareholders may receive cash, securities, or a combination of the two.

Preemptive Rights. There are no preemptive rights associated with the Fund‘s shares.

Conversion Rights. Fund shareholders may convert their shares to another class of shares of the same Fund upon the satisfaction of any then-applicable eligibility requirements as described in the Fund’s current prospectus.

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Redemption Provisions. The Fund’s redemption provisions are described in its current prospectus and elsewhere in this Statement of Additional Information.

Sinking Fund Provisions. The Fund has no sinking fund provisions.

Calls or Assessment. The Fund’s shares, when issued, are fully paid and non-assessable.

Tax Status of the Fund

The Fund expects to qualify each year for treatment as a “regulated investment company” under Subchapter M of the Internal Revenue Code of 1986, as amended (the IRC). This special tax status means that the Fund will not be liable for federal tax on income and capital gains distributed to shareholders. In order to preserve its tax status, the Fund must comply with certain requirements. If the Fund fails to meet these requirements in any taxable year, the Fund will, in some cases, be able to cure such failure, including by paying a fund-level tax, paying interest, making additional distributions, or disposing of certain assets. If the Fund is ineligible to or otherwise does not cure such failure for any year, it will be subject to tax on its taxable income at corporate rates, and all distributions from earnings and profits, including any distributions of net tax-exempt income and net long-term capital gains, will be taxable to shareholders as ordinary income. In addition, the Fund could be required to recognize unrealized gains, pay substantial taxes and interest, and make substantial distributions before regaining its tax status as a regulated investment company.

Dividends received and distributed by the Fund on shares of stock of domestic corporations and certain foreign corporations generally may be eligible to be reported by the Fund, and treated by individual shareholders, as “qualified dividend income” taxed at long-term capital gain rates instead of at higher ordinary income tax rates. Individuals must satisfy holding period and other requirements in order to be eligible for such treatment. Capital gains distributed by the Fund are not eligible for treatment as qualified dividend income.

Dividends received and distributed by the Fund on shares of stock of domestic corporations may be eligible for the dividends-received deduction applicable to corporate shareholders. Corporations must satisfy certain requirements in order to claim the deduction. Capital gains distributed by the Fund are not eligible for the dividends-received deduction.

The Fund may declare a capital gain dividend consisting of the excess (if any) of net realized long-term capital gains over net realized short-term capital losses. Net capital gains for a fiscal year are computed by taking into account any capital loss carryforwards of the Fund. For Fund fiscal years beginning on or after December 22, 2010, capital losses may be carried forward indefinitely and retain their character as either short-term or long-term. Under prior law, net capital losses could be carried forward for eight tax years and were treated as short-term capital losses. The Fund is required to use capital losses arising in fiscal years beginning on or after December 22, 2010, before using capital losses arising in fiscal years beginning prior to December 22, 2010.

FUNDAMENTAL POLICIES

The Fund is subject to the following fundamental investment policies, which cannot be changed in any material way without the approval of the holders of a majority of the Fund’s shares. For these purposes, a “majority” of shares means shares representing the lesser of (1) 67% or more of the Fund’s net assets voted, so long as shares representing more than 50% of the Fund’s net assets are present or represented by proxy or (2) more than 50% of the Fund’s net assets.

Borrowing. The Fund may borrow money only as permitted by the 1940 Act or other governing statute, by the Rules thereunder, or by the SEC or other regulatory agency with authority over the Fund.

Commodities. The Fund may invest in commodities only as permitted by the 1940 Act or other governing statute, by the Rules thereunder, or by the SEC or other regulatory agency with authority over the Fund.

Diversification. The Fund may not change its classification as a “management company” or its subclassifications as an “open-end company” and as a “diversified company” as each such term is defined in the 1940 Act.

Industry Concentration. The Fund will not concentrate its investments in the securities of issuers whose principal business activities are in the same industry.

Loans. The Fund may make loans to another person only as permitted by the 1940 Act or other governing statute, by the Rules thereunder, or by the SEC or other regulatory agency with authority over the Fund.

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Real Estate. The Fund may not invest directly in real estate unless it is acquired as a result of ownership of securities or other instruments. This restriction shall not prevent the Fund from investing in securities or other instruments (1) issued by companies that invest, deal, or otherwise engage in transactions in real estate or (2) backed or secured by real estate or interests in real estate.

Senior Securities. The Fund may not issue senior securities except as permitted by the 1940 Act or other governing statute, by the Rules thereunder, or by the SEC or other regulatory agency with authority over the Fund.

Underwriting. The Fund may not act as an underwriter of another issuer’s securities, except to the extent that the Fund may be deemed to be an underwriter within the meaning of the Securities Act of 1933 (the 1933 Act), in connection with the purchase and sale of portfolio securities.

Compliance with the fundamental policies previously described is generally measured at the time the securities are purchased. Unless otherwise required by the 1940 Act (as is the case with borrowing), if a percentage restriction is adhered to at the time the investment is made, a later change in percentage resulting from a change in the market value of assets will not constitute a violation of such restriction. All fundamental policies must comply with applicable regulatory requirements. For more details, see Investment Strategies, Risks, and Nonfundamental Policies.

None of these policies prevents the Fund from having an ownership interest in Vanguard. As a part owner of Vanguard, the Fund may own securities issued by Vanguard, make loans to Vanguard, and contribute to Vanguard’s costs or other financial requirements. See Management of the Fund for more information.

INVESTMENT STRATEGIES, RISKS, AND NONFUNDAMENTAL POLICIES

Some of the investment strategies and policies described on the following pages and in the Fund’s prospectus set forth percentage limitations on the Fund’s investment in, or holdings of, certain securities or other assets. Unless otherwise required by law, compliance with these strategies and policies will be determined immediately after the acquisition of such securities or assets by the Fund. Subsequent changes in values, net assets, or other circumstances will not be considered when determining whether the investment complies with the Fund’s investment strategies and policies.

The following investment strategies, risks, and policies supplement the Fund’s investment strategies, risks, and policies set forth in the prospectus. With respect to the different investments discussed as follows, the Fund may acquire such investments to the extent consistent with its investment strategies and policies.

Borrowing. A fund’s ability to borrow money is limited by its investment policies and limitations; by the 1940 Act; and by applicable exemptions, no-action letters, interpretations, and other pronouncements issued from time to time by the SEC and its staff or any other regulatory authority with jurisdiction. Under the 1940 Act, a fund is required to maintain continuous asset coverage (that is, total assets including borrowings, less liabilities exclusive of borrowings) of 300% of the amount borrowed, with an exception for borrowings not in excess of 5% of the fund’s total assets made for temporary or emergency purposes. Any borrowings for temporary purposes in excess of 5% of the fund’s total assets must maintain continuous asset coverage. If the 300% asset coverage should decline as a result of market fluctuations or for other reasons, a fund may be required to sell some of its portfolio holdings within three days (excluding Sundays and holidays) to reduce the debt and restore the 300% asset coverage, even though it may be disadvantageous from an investment standpoint to sell securities at that time.

Borrowing will tend to exaggerate the effect on net asset value of any increase or decrease in the market value of a fund’s portfolio. Money borrowed will be subject to interest costs that may or may not be recovered by earnings on the securities purchased with the proceeds of such borrowing. A fund also may be required to maintain minimum average balances in connection with a borrowing or to pay a commitment or other fee to maintain a line of credit; either of these requirements would increase the cost of borrowing over the stated interest rate.

The SEC takes the position that transactions that have a leveraging effect on the capital structure of a fund or are economically equivalent to borrowing can be viewed as constituting a form of borrowing by the fund for purposes of the 1940 Act. These transactions can include entering into reverse repurchase agreements; engaging in mortgage-dollar-roll transactions; selling securities short (other than short sales “against-the-box”); buying and selling certain derivatives (such as futures contracts); selling (or writing) put and call options; engaging in sale-buybacks; entering into firm-commitment and standby-commitment agreements; engaging in when-issued, delayed-delivery, or forward-commitment transactions; and participating in other similar trading practices. (Additional discussion about a number of these transactions can be found on the following pages.) A borrowing transaction will not be considered to constitute the issuance, by a fund, of a

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“senior security,” as that term is defined in Section 18(g) of the 1940 Act, and therefore such transaction will not be subject to the 300% asset coverage requirement otherwise applicable to borrowings by a fund, if the fund maintains an offsetting financial position; segregates liquid assets (with such liquidity determined by the advisor in accordance with procedures established by the board of trustees) equal (as determined on a daily mark-to-market basis) in value to the fund’s potential economic exposure under the borrowing transaction; or otherwise “covers” the transaction in accordance with applicable SEC guidance (collectively, “covers” the transaction). A fund may have to buy or sell a security at a disadvantageous time or price in order to cover a borrowing transaction. In addition, segregated assets may not be available to satisfy redemptions or to fulfill other obligations.

Common Stock. Common stock represents an equity or ownership interest in an issuer. Common stock typically entitles the owner to vote on the election of directors and other important matters, as well as to receive dividends on such stock. In the event an issuer is liquidated or declares bankruptcy, the claims of owners of bonds, other debt holders, and owners of preferred stock take precedence over the claims of those who own common stock.

Debt Securities. A debt security, sometimes called a fixed income security, consists of a certificate or other evidence of a debt (secured or unsecured) on which the issuing company or governmental body promises to pay the holder thereof a fixed, variable, or floating rate of interest for a specified length of time and to repay the debt on the specified maturity date. Some debt securities, such as zero-coupon bonds, do not make regular interest payments but are issued at a discount to their principal or maturity value. Debt securities include a variety of fixed income obligations, including, but not limited to, corporate bonds, government securities, municipal securities, convertible securities, mortgage-backed securities, and asset-backed securities. Debt securities include investment-grade securities, non-investment-grade securities, and unrated securities. Debt securities are subject to a variety of risks, such as interest rate risk, income risk, call risk, prepayment risk, extension risk, inflation risk, credit risk, liquidity risk, and (in the case of foreign securities) country risk and currency risk. The reorganization of an issuer under the federal bankruptcy laws may result in the issuer’s debt securities being cancelled without repayment, repaid only in part, or repaid in part or in whole through an exchange thereof for any combination of cash, debt securities, convertible securities, equity securities, or other instruments or rights in respect to the same issuer or a related entity.

Depositary Receipts. Depositary receipts (also sold as participatory notes) are securities that evidence ownership interests in a security or a pool of securities that have been deposited with a “depository.” Depositary receipts may be sponsored or unsponsored and include American Depositary Receipts (ADRs), European Depositary Receipts (EDRs), and Global Depositary Receipts (GDRs). For ADRs, the depository is typically a U.S. financial institution, and the underlying securities are issued by a foreign issuer. For other depositary receipts, the depository may be a foreign or a U.S. entity, and the underlying securities may have a foreign or a U.S. issuer. Depositary receipts will not necessarily be denominated in the same currency as their underlying securities. Generally, ADRs are issued in registered form, denominated in U.S. dollars, and designed for use in the U.S. securities markets. Other depositary receipts, such as GDRs and EDRs, may be issued in bearer form and denominated in other currencies, and they are generally designed for use in securities markets outside the United States. Although the two types of depositary receipt facilities (sponsored and unsponsored) are similar, there are differences regarding a holder’s rights and obligations and the practices of market participants.

A depository may establish an unsponsored facility without participation by (or acquiescence of) the underlying issuer; typically, however, the depository requests a letter of nonobjection from the underlying issuer prior to establishing the facility. Holders of unsponsored depositary receipts generally bear all the costs of the facility. The depository usually charges fees upon the deposit and withdrawal of the underlying securities, the conversion of dividends into U.S. dollars or other currency, the disposition of noncash distributions, and the performance of other services. The depository of an unsponsored facility frequently is under no obligation to distribute shareholder communications received from the underlying issuer or to pass through voting rights to depositary receipt holders with respect to the underlying securities.

Sponsored depositary receipt facilities are created in generally the same manner as unsponsored facilities, except that sponsored depositary receipts are established jointly by a depository and the underlying issuer through a deposit agreement. The deposit agreement sets out the rights and responsibilities of the underlying issuer, the depository, and the depositary receipt holders. With sponsored facilities, the underlying issuer typically bears some of the costs of the depositary receipts (such as dividend payment fees of the depository), although most sponsored depositary receipt holders may bear costs such as deposit and withdrawal fees. Depositories of most sponsored depositary receipts agree to distribute notices of shareholder meetings, voting instructions, and other shareholder communications and information to the depositary receipt holders at the underlying issuer’s request.

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For purposes of a fund’s investment policies, investments in depositary receipts will be deemed to be investments in the underlying securities. Thus, a depositary receipt representing ownership of common stock will be treated as common stock. Depositary receipts do not eliminate all of the risks associated with directly investing in the securities of foreign issuers.

Derivatives. A derivative is a financial instrument that has a value based on—or “derived from”—the values of other assets, reference rates, or indexes. Derivatives may relate to a wide variety of underlying references, such as commodities, stocks, bonds, interest rates, currency exchange rates, and related indexes. Derivatives include futures contracts and options on futures contracts, certain forward-commitment transactions, options on securities, caps, floors, collars, swap agreements, and certain other financial instruments. Some derivatives, such as futures contracts and certain options, are traded on U.S. commodity and securities exchanges, while other derivatives, such as swap agreements, may be privately negotiated and entered into in the over-the-counter market (OTC Derivatives) or may be cleared through a clearinghouse (Cleared Derivatives) and traded on an exchange or swap execution facility. As a result of the Dodd-Frank Wall Street Reform and Consumer Protection Act (the Dodd-Frank Act), certain swap agreements, such as certain standardized credit default and interest rate swap agreements, must be cleared through a clearinghouse and traded on an exchange or swap execution facility. This could result in an increase in the overall costs of such transactions. While the intent of derivatives regulatory reform is to mitigate risks associated with derivatives markets, the new regulations could, among other things, increase liquidity and decrease pricing for more standardized products while decreasing liquidity and increasing pricing for less standardized products. The risks associated with the use of derivatives are different from, and possibly greater than, the risks associated with investing directly in the securities or assets on which the derivatives are based.

Derivatives are used by some investors for speculative purposes. Derivatives also may be used for a variety of purposes that do not constitute speculation, such as hedging, managing risk, seeking to stay fully invested, seeking to reduce transaction costs, seeking to simulate an investment in equity or debt securities or other investments, and seeking to add value by using derivatives to more efficiently implement portfolio positions when derivatives are favorably priced relative to equity or debt securities or other investments. There is no assurance that any derivatives strategy used by a fund’s advisor will succeed. The other parties to the funds’ OTC Derivatives contracts (usually referred to as “counterparties”) will not be considered the issuers thereof for purposes of certain provisions of the 1940 Act and the IRC, although such OTC Derivatives may qualify as securities or investments under such laws. The funds’ advisors, however, will monitor and adjust, as appropriate, the funds’ credit risk exposure to OTC Derivative counterparties.

Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks, bonds, and other traditional investments. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.

When the fund enters into a Cleared Derivative, an initial margin deposit with a Futures Commission Merchant (FCM) is required. Initial margin deposits are typically calculated as an amount equal to the volatility in market value of a Cleared Derivative over a fixed period. If the value of the fund’s Cleared Derivatives declines, the fund will be required to make additional “variation margin” payments to the FCM to settle the change in value. If the value of the fund’s Cleared Derivatives increases, the FCM will be required to make additional “variation margin” payments to the fund to settle the change in value. This process is known as “marking-to-market” and is calculated on a daily basis.

For OTC Derivatives, the fund is subject to the risk that a loss may be sustained as a result of the insolvency or bankruptcy of the counterparty or the failure of the counterparty to make required payments or otherwise comply with the terms of the contract. Additionally, the use of credit derivatives can result in losses if a fund’s advisor does not correctly evaluate the creditworthiness of the issuer on which the credit derivative is based.

Derivatives may be subject to liquidity risk, which exists when a particular derivative is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with certain OTC Derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.

Derivatives may be subject to pricing or “basis” risk, which exists when a particular derivative becomes extraordinarily expensive relative to historical prices or the prices of corresponding cash market instruments. Under certain market conditions, it may not be economically feasible to initiate a transaction or liquidate a position in time to avoid a loss or take advantage of an opportunity.

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Because certain derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate, or index can result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. A derivative transaction will not be considered to constitute the issuance, by a fund, of a “senior security,” as that term is defined in Section 18(g) of the 1940 Act, and therefore such transaction will not be subject to the 300% asset coverage requirement otherwise applicable to borrowings by a fund, if the fund covers the transaction in accordance with the requirements described under the heading “Borrowing.”

Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to a fund’s interest. A fund bears the risk that its advisor will incorrectly forecast future market trends or the values of assets, reference rates, indexes, or other financial or economic factors in establishing derivative positions for the fund. If the advisor attempts to use a derivative as a hedge against, or as a substitute for, a portfolio investment, the fund will be exposed to the risk that the derivative will have or will develop imperfect or no correlation with the portfolio investment. This could cause substantial losses for the fund. Although hedging strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other fund investments. Many derivatives (in particular, OTC Derivatives) are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to a fund.

Exchange-Traded Funds. A fund may purchase shares of exchange-traded funds (ETFs), including ETF Shares issued by other Vanguard funds. Typically, a fund would purchase ETF shares for the same reason it would purchase (and as an alternative to purchasing) futures contracts: to obtain exposure to all or a portion of the stock or bond market. ETF shares enjoy several advantages over futures. Depending on the market, the holding period, and other factors, ETF shares can be less costly and more tax-efficient than futures. In addition, ETF shares can be purchased for smaller sums, offer exposure to market sectors and styles for which there is no suitable or liquid futures contract, and do not involve leverage.

An investment in an ETF generally presents the same principal risks as an investment in a conventional fund (i.e., one that is not exchange-traded) that has the same investment objective, strategies, and policies. The price of an ETF can fluctuate within a wide range, and a fund could lose money investing in an ETF if the prices of the securities owned by the ETF go down. In addition, ETFs are subject to the following risks that do not apply to conventional funds: (1) the market price of an ETF’s shares may trade at a discount or a premium to their net asset value; (2) an active trading market for an ETF’s shares may not develop or be maintained; and (3) trading of an ETF’s shares may be halted by the activation of individual or marketwide trading halts (which halt trading for a specific period of time when the price of a particular security or overall market prices decline by a specified percentage). Trading of an ETF’s shares may also be halted if the shares are delisted from the exchange without first being listed on another exchange or if the listing exchange’s officials determine that such action is appropriate in the interest of a fair and orderly market or for the protection of investors.

Most ETFs are investment companies. Therefore, a fund’s purchases of ETF shares generally are subject to the limitations on, and the risks of, a fund’s investments in other investment companies, which are described under the heading “Other Investment Companies.”

Vanguard ETF^®* Shares are exchange-traded shares that represent an interest in an investment portfolio held by Vanguard funds. A fund’s investments in Vanguard ETF Shares are also generally subject to the descriptions, limitations, and risks described under the heading “Other Investment Companies,” except as provided by an exemption granted by the SEC that permits registered investment companies to invest in a Vanguard fund that issues ETF Shares beyond the limits of Section 12(d)(1) of the 1940 Act, subject to certain terms and conditions.

* U.S. Patent Nos. 6,879,964; 7,337,138; 7,720,749; 7,925,573; 8,090,646; and 8,417,623.

Foreign Securities. Typically, foreign securities are considered to be equity or debt securities issued by entities organized, domiciled, or with a principal executive office outside the United States, such as foreign corporations and governments. Securities issued by certain companies organized outside the United States may not be deemed to be foreign securities if the company’s principal operations are conducted from the United States or when the company’s equity securities trade principally on a U.S. stock exchange. Foreign securities may trade in U.S. or foreign securities markets. A fund may make foreign investments either directly by purchasing foreign securities or indirectly by purchasing depositary receipts or depositary shares of similar instruments (depositary receipts) for foreign securities. Direct investments in foreign securities may be made either on foreign securities exchanges or in the over-the-counter (OTC)

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markets. Investing in foreign securities involves certain special risk considerations that are not typically associated with investing in securities of U.S. companies or governments.

Because foreign issuers are not generally subject to uniform accounting, auditing, and financial reporting standards and practices comparable to those applicable to U.S. issuers, there may be less publicly available information about certain foreign issuers than about U.S. issuers. Evidence of securities ownership may be uncertain in many foreign countries. As a result, there are multiple risks that could result in a loss to the fund, including, but not limited to, the risk that a fund’s trade details could be incorrectly or fraudulently entered at the time of the transaction. Securities of foreign issuers are generally more volatile and less liquid than securities of comparable U.S. issuers, and foreign investments may be effected through structures that may be complex or confusing. In certain countries, there is less government supervision and regulation of stock exchanges, brokers, and listed companies than in the United States. The risk that securities traded on foreign exchanges may be suspended, either by the issuers themselves, by an exchange, or by government authorities, is also heightened. In addition, with respect to certain foreign countries, there is the possibility of expropriation or confiscatory taxation, political or social instability, war, terrorism, nationalization, limitations on the removal of funds or other assets, or diplomatic developments that could affect U.S. investments in those countries. Additionally, economic or other sanctions imposed on the United States by a foreign country, or imposed on a foreign country or issuer by the United States, could impair a fund’s ability to buy, sell, hold, receive, deliver, or otherwise transact in certain investment securities. Sanctions could also affect the value and/or liquidity of a foreign security.

Although an advisor will endeavor to achieve the most favorable execution costs for a fund’s portfolio transactions in foreign securities under the circumstances, commissions and other transaction costs are generally higher than those on U.S. securities. In addition, it is expected that the custodian arrangement expenses for a fund that invests primarily in foreign securities will be somewhat greater than the expenses for a fund that invests primarily in domestic securities. Additionally, bankruptcy laws vary by jurisdiction and cash deposits may be subject to a custodian’s creditors. Certain foreign governments levy withholding or other taxes against dividend and interest income from, capital gains on the sale of, or transactions in foreign securities. Although in some countries a portion of these taxes is recoverable by the fund, the nonrecovered portion of foreign withholding taxes will reduce the income received from such securities.

The value of the foreign securities held by a fund that are not U.S. dollar-denominated may be significantly affected by changes in currency exchange rates. The U.S. dollar value of a foreign security generally decreases when the value of the U.S. dollar rises against the foreign currency in which the security is denominated, and it tends to increase when the value of the U.S. dollar falls against such currency (as discussed under the heading “Foreign Securities—Foreign Currency Transactions,” a fund may attempt to hedge its currency risks). In addition, the value of fund assets may be affected by losses and other expenses incurred in converting between various currencies in order to purchase and sell foreign securities, as well as by currency restrictions, exchange control regulation, currency devaluations, and political and economic developments.

Foreign Securities—Foreign Currency Transactions. The value in U.S. dollars of a fund’s non-dollar-denominated foreign securities may be affected favorably or unfavorably by changes in foreign currency exchange rates and exchange control regulations, and the fund may incur costs in connection with conversions between various currencies. To seek to minimize the impact of such factors on net asset values, a fund may engage in foreign currency transactions in connection with its investments in foreign securities. A fund will enter into foreign currency transactions only to attempt to “hedge” the currency risk associated with investing in foreign securities. Although such transactions tend to minimize the risk of loss that would result from a decline in the value of the hedged currency, they also may limit any potential gain that might result should the value of such currency increase.