Mutual Fund Summary Prospectus (497k)

October 31, 2013

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Summary

Prospectus

ClearBridge

Energy MLP &

Infrastructure

Fund

Class : Ticker Symbol

A

: LCPAX

C

: LCPCX

FI

: —

R

: —

I

: LCPIX

IS

: LCPSX

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 http://www.leggmason.com/individualinvestors/prospectuses (click on the name of the fund). You can also get this information at no cost by calling the fund at 1-877-721-1926 or by sending an e-mail request to prospectus@leggmason.com, or from your financial intermediary. The fund’s Prospectus, dated August 30, 2013, as supplemented on October 31, 2013, and as may be amended or further supplemented, and the fund’s statement of additional information, dated August 30, 2013, as supplemented on October 31, 2013, and as may be amended or further supplemented, 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 capital appreciation and income.

Fees and expenses of the fund

The accompanying table describes the fees and expenses that you may pay if you buy and hold shares of the fund.

You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $25,000 in funds sold by Legg Mason Investor Services, LLC (“LMIS”), the fund’s distributor. More information about these and other discounts is available from your financial intermediary, in the fund’s Prospectus on page 24 under the heading “Sales charges” and in the fund’s statement of additional information (“SAI”) on page 65 under the heading “Sales Charge Waivers and Reductions.”


Shareholder fees (fees paid directly from your investment)
	Class A	Class C	Class FI	Class R	Class I	Class IS
Maximum sales charge (load) imposed on purchases (as a % of offering price)	5.75	None	None	None	None	None
Maximum deferred sales charge (load) (as a % of the lower of net asset value at purchase or redemption) (may be reduced over time)	Generally, none	1.00	None	None	None	None
Small account fee ¹	$15	$15	None	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 FI	Class R	Class I	Class IS
Management fees	1.00	1.00	1.00	1.00	1.00	1.00
Distribution and service (12b-1) fees	0.25	1.00	0.25	0.50	None	None
Other expenses ²	5.96	5.96	5.96	5.96	5.86	5.76
Total annual fund operating expenses	7.21	7.96	7.21	7.46	6.86	6.76
Fees waived and/or expenses reimbursed ³	(5.61)	(5.61)	(5.61)	(5.61)	(5.61)	(5.61)
Total annual fund operating expenses after waiving fees and/or reimbursing expenses	1.60	2.35	1.60	1.85	1.25	1.15

¹

If your shares are held in a direct account and 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 (with an annual maximum of $15.00 per account). Direct accounts generally include accounts held in the name of the individual investor on the fund’s books and records.

²	“Other expenses” are estimated for the current fiscal year. Actual expenses may differ from estimates.

³

The manager has agreed to waive fees and/or reimburse operating expenses (other than interest, brokerage, taxes and extraordinary expenses) so that total annual operating expenses are not expected to exceed 1.60% for Class A shares, 2.35% for Class C shares, 1.60% for Class FI shares, 1.85% for Class R shares, 1.25% for Class I shares and 1.15% for Class IS shares. These arrangements cannot be terminated prior to December 31, 2014 without the Board of Trustees’ consent. The manager is permitted to recapture amounts waived and/or reimbursed to a class during the same fiscal year if the class’ total annual operating expenses have fallen to a level below the limits described 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:

Ÿ

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

Ÿ

Your investment has a 5% return each year and the fund’s operating expenses remain the same

Ÿ

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
Class A (with or without redemption at end of period)	728	2,103
Class C (with redemption at end of period)	338	1,824
Class C (without redemption at end of period)	238	1,824
Class FI (with or without redemption at end of period)	163	1,621
Class R (with or without redemption at end of period)	188	1,689
Class I (with or without redemption at end of period)	127	1,524
Class IS (with or without redemption at end of period)	117	1,497

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. These costs, which are not reflected in annual fund operating expenses or in the example, affect the fund’s performance. The fund is newly offered; therefore, it does not have a turnover rate to report for the most recent fiscal year.

Principal investment strategies

Under normal circumstances, the fund invests at least 80% of its net assets, plus the amount of borrowings for investment purposes, if any, in energy infrastructure investments. The fund invests in a portfolio of energy infrastructure investments, including master limited partnerships (“MLPs”), “I-Shares” issued by affiliates of MLPs, which represent an indirect ownership of MLP limited partnership interests, general partners of MLPs, fixed income securities, equity securities and equity-related securities, including common stocks, preferred stocks, convertible stocks and other securities convertible into equity securities, of companies providing, building or maintaining energy infrastructure and/or energy infrastructure related services throughout the energy delivery supply chain. Such energy infrastructure companies may be involved in extraction ( e.g. , oil drilling services), mid-stream activities ( e.g. , transporting or processing energy assets), storage or other related activities and include energy related utilities companies.

The fund may invest up to 25% of its total assets directly in securities of MLPs that are treated for U.S. federal income tax purposes as qualified publicly traded partnerships (“QPTPs”). This 25% limitation applies generally to MLPs that focus on commodity and

energy-related industries. The fund may invest in issuers with any market capitalization. The fund may invest up to 50% of its net assets in foreign securities. The fund may also invest in securities of issuers in emerging market countries.

The fund may seek to generate current income from short-term gains earned through a derivative strategy using options, which may consist of writing (selling) call options on equity securities in its portfolio (“covered calls”) and on broader equity market indexes, or writing (selling) put options on such securities or indexes. The fund may invest up to 20% of its net assets in options on equity securities and equity market indexes. The fund may also enter into various other derivative transactions for both hedging and non-hedging purposes, including for purposes of enhancing returns. These derivative transactions include, but are not limited to, forward foreign currency contracts and currency swaps.

The fund may invest up to 20% of its assets in fixed income securities of any credit quality, including securities rated below investment grade or, if unrated, deemed by the subadviser to be of comparable quality (“junk bonds”).

Certain risks

Risk is inherent in all investing. There is no assurance that the fund will meet its investment objective. 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. The following is a summary description of certain risks of investing in the fund.

Stock market and equity securities risk. The securities markets are volatile and the market prices of the fund’s securities may decline generally. Securities fluctuate in price based on changes in a company’s financial condition and overall market and economic conditions. If the market prices of the securities owned by the fund fall, the value of your investment in the fund will decline. The financial crisis that began in 2008 has caused a significant decline in the value and liquidity of many securities of issuers worldwide. In response to the crisis, the U.S. and other governments and the Federal Reserve and certain foreign central banks have taken steps to support financial markets. The withdrawal of this support, failure of efforts to respond to the crisis, or investor perception that such efforts are not succeeding could also negatively affect financial markets generally as well as the value and liquidity of certain securities. In addition, policy and legislative changes in the United States and in other countries are changing many aspects of financial regulation. The impact of these changes on the markets, and the practical implications for market participants, may not be fully known for some time.

MLP risk. Holders of MLP units have limited control and voting rights on matters affecting the partnership. In addition, there are certain tax risks associated with an investment in MLP units and the potential for conflicts of interest exist between common unit holders and the general partner, including those arising from incentive distribution payments. The benefit the fund derives from investment in MLP units is largely dependent on the MLPs being treated as partnerships and not as corporations for federal income tax purposes. If an MLP were classified as a corporation for federal income tax purposes, the MLP may incur significant federal and state tax liability, likely causing a reduction in the value of the fund’s shares. MLPs are generally considered interest-rate sensitive investments, and during periods of interest rate volatility, may not provide attractive returns.

Fixed income securities risk. Fixed income securities are subject to a number of risks, including credit, market and interest rate risks. Credit risk is the risk that the issuer or obligor will not make timely payments of principal and interest. Changes in an issuer’s credit rating or the market’s perception of an issuer’s creditworthiness may also affect the value of the fund’s investment in that issuer. Market risk is the risk that the fixed income markets may become volatile and less liquid, and the market value of an investment may move up or down, sometimes quickly or unpredictably. Interest rate risk is the risk that the value of a fixed income security will fall when interest rates rise. In general, the longer the maturity and the lower the credit quality of a fixed income security, the more likely its value will decline.

Foreign investments and emerging markets risk. The fund’s investments in securities of foreign issuers or issuers with significant exposure to foreign markets involve additional risk. Foreign countries in which the fund may invest may have markets that are less liquid, less regulated and more volatile than U.S. markets. The value of the fund’s investments may decline because of factors affecting the particular issuer as well as foreign markets and issuers generally, such as unfavorable government actions, and political or financial instability. Lack of information may also affect the value of these securities.

Risks of investing in Canada. Investments in Canadian issuers may subject the fund to economic risk specific to Canada. Among other things, the Canadian economy is heavily dependent on relationships with certain key trading partners, including the United States, European Union (the “EU”) countries and China. In addition, Canada is a large supplier of natural resources ( e.g. , oil, natural gas and agricultural products). As a result, the Canadian economy is sensitive to fluctuations in certain commodity prices.

Currency risk. The value of investments in securities denominated in foreign currencies increases or decreases as the rates of exchange between those currencies and the U.S. dollar change. Currency conversion costs and currency fluctuations could erase investment gains or add to investment losses. Currency exchange rates can be volatile, and are affected by factors such as general economic conditions, the actions of the U.S. and foreign governments or central banks, the imposition of currency controls and speculation.

The fund’s ability to use forward foreign currency transactions successfully depends on a number of factors,

including the forward foreign currency transactions being available at prices that are not too costly, the availability of liquid markets and the ability of the portfolio managers to accurately predict the direction of changes in currency exchange rates. Currency transactions are subject to counterparty risk, which is the risk that the other party in the transaction will not fulfill its contractual obligation.

Income-producing securities risk. The fund’s emphasis on equity and equity-related securities that produce income or other distributions involves the risk that such securities may fall out of favor with investors and underperform the market. Also, an issuer may reduce or eliminate its income payments or other distributions. The distributions received by the fund may not qualify as income for fund investors.

Issuer risk. The value 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, often due to disappointing earnings reports by the issuer, unsuccessful products or services, loss of major customers, major litigation against the issuer or changes in government regulations affecting the issuer or the competitive environment. The fund may experience a substantial or complete loss on an individual security. Historically, the prices of securities of small and medium capitalization companies have generally gone up or down more than those of large capitalization companies, although even large capitalization companies may fall out of favor with investors.

Non-diversification risk. The fund is classified as “non-diversified,” which means it may invest a larger percentage of its assets in a smaller number of issuers than a diversified fund. To the extent the fund invests its assets in a small number of issuers, the fund will be more susceptible to negative events affecting those issuers than a diversified fund.

Large capitalization company risk. Large capitalization companies may fall out of favor with investors.

Small and medium capitalization company risk. The fund will be exposed to additional risks as a result of its investments in the securities of small and medium capitalization companies. Small and medium capitalization companies may fall out of favor with investors; may have limited product lines, operating histories, markets or financial resources; or may be dependent upon a limited management group. The prices of securities of small and medium capitalization companies generally are more volatile than those of large capitalization companies and are more likely to be adversely affected than large capitalization companies by changes in earnings results and investor expectations or poor economic or market conditions, including those experienced during a recession. Securities of small and medium capitalization companies may underperform large capitalization companies, may be harder to sell at times and at prices the portfolio managers believe appropriate and may offer greater potential for losses.

Derivatives risk. Using derivatives may have a leveraging effect, which may result in a disproportionate increase in fund losses on the investment, and reduce opportunities for gains when market prices, interest rates or the derivative instruments themselves behave in a way not anticipated by the fund. Using derivatives also can increase fund volatility. Derivatives may be difficult to sell, unwind or value, and the counterparty may default on its obligations to the fund. Recent legislation calls for new regulation of the derivatives markets. The extent and impact of the regulation are not yet fully known and may not be for some time. New regulation of derivatives may make them more costly, may limit their availability, or may otherwise adversely affect their value or performance.

Energy and energy infrastructure sector risk. The fund is subject to the risk of concentrating investments in the energy sector, which makes it more susceptible to factors adversely affecting issuers within that industry than would a fund investing in a more diversified portfolio of securities. A downturn in the energy sector of the economy could have an adverse impact on the fund. At times, the performance of securities of companies in the energy sector of the economy may lag the performance of other sectors or the broader market as a whole. Energy infrastructure companies are affected by worldwide energy prices and costs related to energy production. These companies may have significant operations in areas at risk for natural disasters, social unrest and environmental damage. These companies may also be at risk for increased government regulation and intervention, energy conservation efforts, litigation and negative publicity and perception.

Utilities sector risk. Investments in energy related utilities companies involve special considerations, including the risk of changing commodity prices, government regulation and oversight, increased tariffs, changes in tax laws, interest rate fluctuations and changes in the cost of providing utility services. The utilities sector is also subject to potential terrorist attacks, natural disasters and severe weather conditions, as well as regulatory and operational burdens associated with the operation and maintenance of facilities.

Growth and value investing risk. Growth or value securities as a group may be out of favor and underperform the overall equity market while the market concentrates on other types of securities. Growth securities typically are very sensitive to market movements because their market prices tend to reflect future expectations. When it appears those expectations will not be met, the prices of growth securities typically fall. The value approach to investing involves the risk that stocks may remain undervalued.

Liquidity risk. Some assets held by the fund may be difficult to sell, or illiquid, particularly during times of market turmoil. Illiquid assets may also be difficult to value. If the fund is forced to sell an illiquid asset to meet redemption requests or other cash needs, the fund may be forced to sell at a loss.

Valuation risk. The sales price the fund could receive for any particular portfolio investment may differ from the

fund’s valuation of the investment, particularly for securities that trade in thin or volatile markets or that are valued using a fair value methodology. Investors who purchase or redeem fund shares on days when the fund is holding fair-valued securities may receive fewer or more shares or lower or higher redemption proceeds than they would have received if the fund had not fair-valued the security or had used a different valuation methodology.

Portfolio selection risk. The value of your investment may decrease if the subadviser’s judgment about the attractiveness, value or market trends affecting a particular security, industry or sector or about market movements is incorrect.

Risk of increase in expenses. Your actual costs of investing in the fund may be higher than the expenses shown in “Annual fund operating expenses” for a variety of reasons. For example, expense ratios may be higher than those shown if a fee limitation is changed or terminated or if average net assets are lower than estimated. Net assets are more likely to decrease and fund expense ratios are more likely to increase when markets are volatile.

These risks are discussed in more detail in the fund’s Prospectus or in the SAI.

Performance

The fund has not yet operated for a full calendar year. Once the fund has a performance record of at least one calendar year, a bar chart and performance table will be included in this Prospectus.

Management

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

Subadviser: ClearBridge Investments, LLC (“ClearBridge”)

Portfolio managers: Michael Clarfeld, CFA and Chris Eades. Mr. Clarfeld (Managing Director and Portfolio Manager of ClearBridge) and Chris Eades (Managing Director, Director of Research and Portfolio Manager of ClearBridge) have been portfolio managers of the fund since its inception.

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.

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

Investment minimum initial/additional investment ($)

Class A

Class C

Class FI

Class R

Class I

Class IS

General

1,000/50

N/A

1 million/None*

N/A

Uniform Gifts or Transfers to Minor Accounts

1,000/50

N/A

1 million/None*

N/A

IRAs

250/50

N/A

1 million/None*

N/A

SIMPLE IRAs

None/None

N/A

1 million/None*

N/A

Systematic Investment Plans

50/50

N/A

1 million/None*

N/A

Clients of Eligible Financial Intermediaries

None/None

N/A

None/None

N/A

None/None

N/A

Eligible Investment Programs

None/None

N/A

None/None

N/A

Retirement Plans with omnibus accounts held on the books of the fund and certain rollover IRAs

None/None

Other Retirement Plans

None/None

N/A

1 million/None*

N/A

Institutional Investors

1,000/50

N/A

1 million/None

*	Available to investors investing directly with the fund.

Your financial intermediary may impose different investment minimums.

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 financial intermediary, or, if you hold your shares or plan to purchase shares through the fund, you should contact the fund by phone at 1-877-721-1926 or by mail at Legg Mason Funds, P.O. Box 55214, Boston, MA 02205-8504.

Tax information

The fund’s distributions are taxable as ordinary income or capital gain, except when your investment is through an IRA, 401(k) or other tax-advantaged account.

Payments to broker/dealers and other financial intermediaries

The fund’s related companies may pay broker/dealers or other financial intermediaries (such as a bank or an insurance company) for the sale of fund shares and related services. These payments create a conflict of interest by influencing your broker/dealer or other intermediary or its employees or associated persons to recommend the fund over another investment. Ask your financial adviser or salesperson or visit your financial intermediary’s or salesperson’s website for more information.

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