Legg Mason Global Asset Management Trust

01/28/2022 | Press release | Distributed by Public on 01/28/2022 05:01

Summary Prospectus by Investment Company (Form 497K)

BrandywineGLOBAL - Dynamic US Large Cap Value Fund
Summary Prospectus January 28, 2022

Share class (Symbol): A (LMBJX), C (LMBBX), R (LMBHX), I (LMBEX), IS (LMBGX)

BrandywineGLOBAL -

DYNAMIC US LARGE CAP

VALUE FUND

Before you invest, you may want to review the fund's Prospectus, which contains more information about the fund and its risks. You can find the fund's Prospectus and other information about the fund, including the fund's statement of additional information and shareholder reports, online at www.franklintempleton.com/mutualfundsliterature. You can also get this information at no cost by calling the fund at 877-6LM-FUND/656-3863 or by sending an e-mail request to [email protected], or from your financial intermediary. The fund's Prospectus and statement of additional information, each dated January 28, 2022 (as may be amended or supplemented from time to time), and the independent registered public accounting firm's report and financial statements in the fund's annual report to shareholders, dated September 30, 2021, are incorporated by reference into this Summary Prospectus.

INVESTMENT PRODUCTS: NOT FDIC INSURED • NO BANK GUARANTEE • MAY LOSE VALUE

Investment objective

The fund seeks to provide long-term capital appreciation by quantitatively investing in U.S. equities.

Fees and expenses of the fund

The accompanying table describes the fees and expenses that you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.

You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $25,000 in Legg Mason funds or other eligible investments as described below. More information about these and other discounts is available from your Service Agent, in the fund's Prospectus on page 17 under the heading "Additional information about each share class," in the appendix titled "Appendix: Waivers and Discounts Available from Certain Service Agents" on page A-1 of the fund's Prospectus and in the fund's Statement of Additional Information ("SAI") on page 87 under the heading "Sales Charge Waivers and Reductions for Class A Shares." "Service Agents" include banks, brokers, dealers, insurance companies, investment advisers, financial consultants or advisers, mutual fund supermarkets and other financial intermediaries that have entered into an agreement with Franklin Distributors, LLC ("Franklin Distributors" or the "Distributor"), the fund's distributor, to sell shares of the fund.

If you purchase Class I shares or Class IS shares through a Service Agent acting solely as an agent on behalf of its customers, that Service Agent may charge you a commission. Such commissions, if any, are not charged by the fund and are not reflected in the fee table or expense example below.

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Shareholder fees
(fees paid directly from your investment)
Class A Class C Class R Class I Class IS
Maximum sales charge (load) imposed on purchases (as a % of offering price) 5.751,2 None None None None
Maximum deferred sales charge (load) (as a % of the lower of net asset value at purchase or redemption)3 None4 1.00 None None None
Small account fee5 $15 $15 None None None
Annual fund operating expenses (%)
(expenses that you pay each year as a percentage of the value of your investment)
Class A Class C Class R Class I Class IS
Management fees 0.55 0.55 0.55 0.55 0.55
Distribution and/or service (12b-1) fees 0.25 1.00 0.50 None None
Other expenses 0.28 0.20 0.56 0.19 0.12
Total annual fund operating expenses 1.08 1.75 1.61 0.74 0.67
Fees waived and/or expenses reimbursed6 - - (0.26) - (0.02)
Total annual fund operating expenses after waiving fees and/or reimbursing expenses 1.08 1.75 1.35 0.74 0.65
1

The sales charge is waived for shareholders purchasing Class A shares through accounts where Franklin Distributors is the broker-dealer of record ("Distributor Accounts").

2

Shareholders purchasing Class A shares through certain Service Agents or in certain types of accounts may be eligible for a waiver of the sales charge. For additional information, see "Additional information about each share class - Sales charges" in the Prospectus.

3

Maximum deferred sales charge (load) may be reduced over time.

4

You may buy Class A shares in amounts of $1,000,000 or more at net asset value (without an initial sales charge), but if you redeem those shares within 18 months of their purchase, you will pay a contingent deferred sales charge of 1.00%.

5

If the value of your account is below $1,000 ($250 for retirement plans that are not employer-sponsored), the fund may charge you a fee of $3.75 per account that is determined and assessed quarterly by the fund or your Service Agent (with an annual maximum of $15.00 per account). Please contact your Service Agent or the fund for more information.

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6

The manager has agreed to waive fees and/or reimburse operating expenses (other than interest, brokerage commissions, dividend expense on short sales, taxes, extraordinary expenses and acquired fund fees and expenses) so that the ratio of total annual fund operating expenses will not exceed 1.10% for Class A shares, 1.85% for Class C shares, 1.35% for Class R shares, 0.75% for Class I shares and 0.65% for Class IS shares, subject to recapture as described below. In addition, the ratio of total annual fund operating expenses for Class IS shares will not exceed the ratio of total annual fund operating expenses for Class I shares, subject to recapture as described below. These arrangements cannot be terminated prior to December 31, 2023 without the Board of Trustees' consent. The manager is permitted to recapture amounts waived and/or reimbursed to a class within three years after the fiscal year in which the manager earned the fee or incurred the expense if the class' total annual fund operating expenses have fallen to a level below the limits described above. In no case will the manager recapture any amount that would result, on any particular business day of the fund, in the class' total annual fund operating expenses exceeding the applicable limits described above or any other lower limit then in effect. In addition, the manager has agreed to waive the fund's management fee to an extent sufficient to offset the net management fee payable in connection with any investment in an affiliated money market fund. This management fee waiver is not subject to the recapture provision discussed above.

Example

This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes:

You invest $10,000 in the fund for the time periods indicated

Your investment has a 5% return each year and the fund's operating expenses remain the same (except that any applicable fee waiver or expense reimbursement is reflected only through its expiration date)

You reinvest all distributions and dividends without a sales charge

Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Number of years you own your shares ($)
1 year 3 years 5 years 10 years
Class A (with or without redemption at end of period) 679 899 1,136 1,817
Class C (with redemption at end of period) 278 552 950 1,886
Class C (without redemption at end of period) 178 552 950 1,886
Class R (with or without redemption at end of period) 137 482 851 1,888
Class I (with or without redemption at end of period) 76 237 412 919
Class IS (with or without redemption at end of period) 66 212 371 832

Portfolio turnover. The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 83% of the average value of its portfolio.

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BrandywineGLOBAL - Dynamic US Large Cap Value Fund

Principal investment strategies

The portfolio managers use a proprietary quantitative model to identify investments for the fund. To identify investments, the model evaluates multiple quantitative characteristics for each potential stock investment and applies specific rules to select stocks for investment based on these characteristics. The fund will typically invest in a stock when it meets the large capitalization threshold and its price-to-earnings or price-to-book ratios indicate a potentially attractive valuation and the quantitative model ranks it with a high multifactor score.

The fund will only invest in U.S. traded companies, which may include companies incorporated outside the U.S. which conduct a significant portion of their activities in the U.S. and are considered U.S. companies in the Russell U.S. indices. The fund normally invests at least 80% of its net assets, plus the amount of borrowings for investment purposes, if any, in issuers domiciled, or having their principal activities, in the United States, at the time of investment or other instruments with similar economic characteristics. In addition, the fund normally invests at least 80% of its net assets in equity securities of large capitalization companies. Large capitalization companies are those companies with market capitalizations similar to companies in the Russell 1000® Index (the "Index"). The size of the companies in the Index changes with market conditions and the composition of the Index. As of November 30, 2021, the median market capitalization of a company in the Index was approximately $14.45 billion and the dollar-weighted average market capitalization of the companies in the Index was approximately $603.07 billion.

The fund may have significant positions in particular sectors from time to time. In addition, the fund may engage in active and frequent trading to achieve its investment objective.

Principal risks

Risk is inherent in all investing. The value of your investment in the fund, as well as the amount of return you receive on your investment, may fluctuate significantly. You may lose part or all of your investment in the fund or your investment may not perform as well as other similar investments. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or by any bank or government agency. The following is a summary description of certain risks of investing in the fund.

Stock market and equity securities risk. The stock markets are volatile and the market prices of the fund's equity securities may decline generally. Equity securities may include warrants, rights, exchange-traded and over-the-counter common stocks, preferred stock, depositary receipts, trust certificates, limited partnership interests and shares of other investment companies, including exchange-traded funds and real estate investment trusts. Equity securities may have greater price volatility than other asset classes, such as fixed income securities, and may fluctuate in price based on actual or perceived changes in a company's financial condition and overall market and economic conditions and perceptions. If the market prices of the equity securities owned by the fund fall, the value of your investment in the fund will decline. If the fund holds equity securities in a company that becomes insolvent, the fund's interests in the company will be subordinated to the interests of debtholders and general creditors of the company, and the fund may lose its entire investment.

Value investing risk. The value approach to investing involves the risk that stocks may remain undervalued for long periods, undervaluation may become more severe, or perceived

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undervaluation may actually represent intrinsic value. Value stocks may underperform the overall equity market for an extended period while the market concentrates on growth stocks.

Large capitalization company risk. Large capitalization companies may fall out of favor with investors based on market and economic conditions. In addition, larger companies may not be able to attain the high growth rates of successful smaller companies and may be less capable of responding quickly to competitive challenges and industry changes. As a result, the fund's value may not rise as much as, or may fall more than, the value of funds that focus on companies with smaller market capitalizations.

Portfolio management risk. The value of your investment may decrease if the subadviser's judgment about the attractiveness or value of, or market trends affecting, a particular security, industry, sector or region, or about market movements, is incorrect or does not produce the desired results, or if there are imperfections, errors or limitations in the models, tools and data used by the subadviser. In addition, the fund's investment strategies or policies may change from time to time. Those changes may not lead to the results intended by the subadviser and could have an adverse effect on the value or performance of the fund.

Model risk. The subadviser's investment model may not adequately take into account certain factors and may result in the fund having a lower return than if the fund were managed using another model or investment strategy. When a model or data used in managing the fund contains an error, or is incorrect or incomplete, any investment decision made in reliance on the model or data may not produce the desired results and the fund may realize losses.

Market events risk. The market values of securities or other assets will fluctuate, sometimes sharply and unpredictably, due to changes in general market conditions, overall economic trends or events, governmental actions or intervention, actions taken by the U.S. Federal Reserve or foreign central banks, market disruptions caused by trade disputes or other factors, political developments, investor sentiment, the global and domestic effects of a pandemic, and other factors that may or may not be related to the issuer of the security or other asset. Economies and financial markets throughout the world are increasingly interconnected. Economic, financial or political events, trading and tariff arrangements, public health events, terrorism, natural disasters and other circumstances in one country or region could have profound impacts on global economies or markets. As a result, whether or not the fund invests in securities of issuers located in or with significant exposure to the countries directly affected, the value and liquidity of the fund's investments may be negatively affected.

The rapid and global spread of a highly contagious novel coronavirus respiratory disease, designated COVID-19, has resulted in extreme volatility in the financial markets; reduced liquidity of many instruments; restrictions on international and, in some cases, local travel; significant disruptions to business operations (including business closures); strained healthcare systems; disruptions to supply chains, consumer demand and employee availability; and widespread uncertainty regarding the duration and long-term effects of this pandemic. Some sectors of the economy and individual issuers have experienced particularly large losses. In addition, the COVID-19 pandemic may result in a sustained domestic or even global economic downturn or recession, domestic and foreign political and social instability, damage to diplomatic and international trade relations and increased volatility and/or decreased liquidity in the securities markets. Developing or emerging market countries may be more impacted by the

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BrandywineGLOBAL - Dynamic US Large Cap Value Fund

COVID-19 pandemic as they may have less established health care systems and may be less able to control or mitigate the effects of the pandemic. The ultimate economic fallout from the pandemic, and the long-term impact on economies, markets, industries and individual issuers, are not known. The U.S. government and the Federal Reserve, as well as certain foreign governments and central banks, have taken extraordinary actions to support local and global economies and the financial markets in response to the COVID-19 pandemic. This and other government intervention into the economy and financial markets to address the COVID-19 pandemic may not work as intended, particularly if the efforts are perceived by investors as being unlikely to achieve the desired results. Government actions to mitigate the economic impact of the pandemic have resulted in a large expansion of government deficits and debt, the long term consequences of which are not known. The COVID-19 pandemic could adversely affect the value and liquidity of the fund's investments, impair the fund's ability to satisfy redemption requests, and negatively impact the fund's performance. In addition, the outbreak of COVID-19, and measures taken to mitigate its effects, could result in disruptions to the services provided to the fund by its service providers.

Issuer risk. The market price of a security can go up or down more than the market as a whole and can perform differently from the value of the market as a whole, due to factors specifically relating to the security's issuer, such as disappointing earnings reports by the issuer, unsuccessful products or services, loss of major customers, changes in management, corporate actions, negative perception in the marketplace, or major litigation or changes in government regulations affecting the issuer or the competitive environment. An individual security may also be affected by factors relating to the industry or sector of the issuer. The fund may experience a substantial or complete loss on an individual security. A change in financial condition or other event affecting a single issuer may adversely impact the industry or sector of the issuer or securities markets as a whole.

Redemptions by affiliated funds and by other significant investors. The fund may be an investment option for mutual funds and ETFs that are managed by LMPFA and its affiliates, including Franklin Templeton investment managers, as "funds of funds," unaffiliated mutual funds and ETFs and other investors with substantial investments in the fund. As a result, from time to time, the fund may experience relatively large redemptions and could be required to liquidate its assets at inopportune times or at a loss or depressed value, which could cause the value of your investment to decline.

Portfolio turnover risk. Active and frequent trading may increase a shareholder's tax liability and the fund's transaction costs, which could detract from fund performance.

Industry or sector focus risk. Although the fund does not employ an industry or sector focus, the fund may be susceptible to an increased risk of loss, including losses due to events that adversely affect the fund's investments more than the market as a whole, to the extent that the fund has greater exposure to the securities of a particular issuer or issuers within the same industry or sector.

Cybersecurity risk. Cybersecurity incidents, both intentional and unintentional, may allow an unauthorized party to gain access to fund assets, fund or customer data (including private shareholder information), or proprietary information, cause the fund, the manager, the subadviser and/or their service providers (including, but not limited to, fund accountants,

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custodians, sub-custodians, transfer agents and financial intermediaries) to suffer data breaches, data corruption or loss of operational functionality or prevent fund investors from purchasing, redeeming or exchanging shares or receiving distributions. The fund, the manager, and the subadviser have limited ability to prevent or mitigate cybersecurity incidents affecting third party service providers, and such third party service providers may have limited indemnification obligations to the fund or the manager. Cybersecurity incidents may result in financial losses to the fund and its shareholders, and substantial costs may be incurred in order to prevent any future cybersecurity incidents. Issuers of securities in which the fund invests are also subject to cybersecurity risks, and the value of these securities could decline if the issuers experience cybersecurity incidents.

These and other risks are discussed in more detail in the Prospectus or in the Statement of Additional Information.

Performance

The accompanying bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund's performance from year to year for Class IS shares. The table shows the average annual total returns of each class of the fund that has been in operation for at least one full calendar year and also compares the fund's performance with the average annual total returns of an index or other benchmark. Performance prior to October 31, 2014 in the bar chart and the table is that of the fund's predecessor. Performance for classes other than those shown may vary from the performance shown to the extent the expenses for those classes differ. The fund makes updated performance information, including its current net asset value, available at www.franklintempleton.com/mutualfunds (select fund and share class), or by calling the fund at 877-6LM-FUND/656-3863.

The fund's past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.

Sales charges are not reflected in the accompanying bar chart, and if those charges were included, returns would be less than those shown.

This fund is the successor to an unregistered private fund (the "Predecessor"). The performance in the accompanying bar chart and table prior to the fund's inception is that of the Predecessor. On October 31, 2014, the Predecessor transferred its assets to the fund in exchange for the fund's Class IS shares. The investment policies, objectives, guidelines and restrictions of the fund are in all material respects equivalent to those of the Predecessor. In addition, the Predecessor's portfolio managers are the current portfolio managers of the fund. As a mutual fund registered under the Investment Company Act of 1940 (the "1940 Act"), the fund is subject to certain restrictions under the 1940 Act and the Internal Revenue Code of 1986, as amended (the "Code") to which the Predecessor was not subject. Had the Predecessor been registered under the 1940 Act and been subject to the provisions of the 1940 Act and the Code, its investment performance could have been adversely affected, but these restrictions are not expected to have a material effect on the fund's investment program. The performance information reflects the gross expenses of the Predecessor adjusted to reflect the higher fees and expenses of Class IS shares of the fund. The performance is shown net of an annual management fee of 0.55% and other expenses of 0.10% which reflects the application of the

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BrandywineGLOBAL - Dynamic US Large Cap Value Fund

Class IS shares' expense limitation agreement. If the expense limitation agreement were not applicable, expenses would be higher and performance lower.

The Predecessor did not have distribution policies. The Predecessor was an unregistered private fund, did not qualify as a regulated investment company for federal income tax purposes and did not pay dividends or distributions.

Best Quarter (06/30/2020): 18.39 Worst Quarter (03/31/2020): (25.83)

Average annual total returns (%)
(for periods ended December 31, 2021)
Class IS 1 year 5 years 10 years Since inception Inception date
Return before taxes 29.17 14.36 14.77
Return after taxes on distributions 22.34 11.75 13.27
Return after taxes on distributions and sale of fund shares 17.88 10.54 11.87
Other Classes (Return before taxes only)
Class A 21.32 12.54 N/A 9.93 11/03/2014
Class C 26.76 13.04 N/A 10.01 11/03/2014
Class R 28.30 13.57 N/A 10.52 11/03/2014
Class I 29.12 14.28 N/A 11.18 11/03/2014
Russell 1000 Value Index (reflects no deduction for fees, expenses or taxes)1 25.16 11.16 12.97
S&P 500 Index (reflects no deduction for fees, expenses or taxes)2 28.71 18.47 16.55
1

For Class A, Class C, Class R and Class I shares, for the period from the class' inception date to December 31, 2021, the average annual total return of the Russell 1000 Value Index was 9.91%.

2

For Class A, Class C, Class R and Class I shares, for the period from the class' inception date to December 31, 2021, the average annual total return of the S&P 500 Index was 14.95%.

The after-tax returns are shown only for Class IS shares, are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement

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accounts. After-tax returns for classes other than Class IS will vary from returns shown for Class IS.

Management

Investment manager: Legg Mason Partners Fund Advisor, LLC ("LMPFA")

Subadviser: Brandywine Global Investment Management, LLC ("Brandywine Global")

Portfolio managers: Primary responsibility for the day-to-day management of the fund lies with the following portfolio managers.

Portfolio manager Title Portfolio manager of the fund since
Michael Fleisher Portfolio Manager 2007*
Henry Otto Portfolio Manager 2007*
Steven Tonkovich Portfolio Manager 2007*
*

Reflects the commencement of operations of the Predecessor.

Purchase and sale of fund shares

You may purchase, redeem or exchange shares of the fund each day the New York Stock Exchange is open, at the fund's net asset value determined after receipt of your request in good order, subject to any applicable sales charge.

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BrandywineGLOBAL - Dynamic US Large Cap Value Fund

The fund's initial and subsequent investment minimums generally are set forth in the accompanying table:

Investment minimum initial/additional investment ($)
Class A Class C1 Class R Class I Class IS
General 1,000/50 1,000/50 N/A 1 million/None2 N/A
Uniform Gifts or Transfers to Minor Accounts 1,000/50 1,000/50 N/A 1 million/None2 N/A
IRAs 250/50 250/50 N/A 1 million/None2,3 N/A3
SIMPLE IRAs None/None None/None N/A 1 million/None2 N/A
Systematic Investment Plans 25/25 25/25 N/A 1 million/None2,4 N/A4
Clients of Eligible Financial Intermediaries None/None N/A None/None None/None5 None/None5
Eligible Investment Programs None/None N/A None/None None/None None/None
Omnibus Retirement Plans None/None None/None None/None None/None None/None
Individual Retirement Plans except as noted None/None None/None N/A 1 million/None2 N/A
Institutional Investors 1,000/50 1,000/50 N/A 1 million/None 1 million/None
1

Class C shares are not available for purchase through Distributor Accounts.

2

Available to investors investing directly with the fund.

3

IRA accountholders who purchase Class I or Class IS shares through a Service Agent acting as agent on behalf of its customers are subject to the initial and subsequent minimums of $250/$50. If a Service Agent does not have this arrangement in place with the Distributor, the initial and subsequent minimums listed in the table apply. Please contact your Service Agent for more information.

4

Investors investing through a Systematic Investment Plan who purchase Class I or Class IS shares through a Service Agent acting as agent on behalf of its customers are subject to the initial and subsequent minimums of $25/$25. If a Service Agent does not have this arrangement in place with the Distributor, the initial and subsequent minimums listed in the table apply. Please contact your Service Agent for more information.

5

Individual investors who purchase Class I shares or Class IS shares through a Service Agent acting as agent on behalf of its customers are subject to the initial and subsequent minimums of $1,000/$50. If a Service Agent does not have this arrangement in place with the Distributor, the initial and subsequent minimums listed in the table apply. Please contact your Service Agent for more information.

Your Service Agent may impose higher or lower investment minimums, or may impose no minimum investment requirement.

For more information about how to purchase, redeem or exchange shares, and to learn which classes of shares are available to you, you should contact your Service Agent, or, if you hold your shares or plan to purchase shares through the fund, you should contact the fund by phone at 877-6LM-FUND/656-3863, by regular mail at Legg Mason Funds, P.O. Box 33030, St. Petersburg, FL 33733-8030 or by express, certified or registered mail at Legg Mason Funds, 100 Fountain Parkway, St. Petersburg, FL 33716-1205.

Tax information

The fund's distributions are generally taxable as ordinary income or capital gains.

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Payments to broker/dealers and other financial intermediaries

The fund's related companies pay Service Agents for the sale of fund shares, shareholder services and other purposes. These payments create a conflict of interest by influencing your Service Agent or its employees or associated persons to recommend the fund over another investment. Ask your financial adviser or salesperson or visit your Service Agent's or salesperson's website for more information.

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