Summary Prospectus by Investment Company - Form 497K

		SUMMARY PROSPECTUS
		FRANKLIN LOW DURATION U.S. GOVERNMENT SECURITIES FUND
		FRANKLIN INVESTORS SECURITIES TRUST
		March 1, 2024 as amended, May 1, 2024

Class A	Class A1	Class C	Class R6	Advisor Class
FISAX	FAUGX	FCSCX	FAURX	FAUZX

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, statement of additional information, reports to shareholders and other information about the Fund online at www.franklintempleton.com/prospectus. You can also get this information at no cost by calling (800) DIAL BEN/342-5236 or by sending an e-mail request to [email protected]. The Fund's prospectus and statement of additional information, both dated March 1, 2024, as may be supplemented, are all incorporated by reference into this Summary Prospectus.

FRANKLIN LOW DURATION U.S. GOVERNMENT SECURITIES FUND
SUMMARY PROSPECTUS

Fund Summary

Investment Goal

High level of current income, consistent with preservation of capital.

Fees and Expenses of the Fund

These tables describe the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. You may pay other fees (including on Class R6 and Advisor Class shares), 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 in Class A if you and your family invest, or agree to invest in the future, at least $100,000 in Franklin Templeton funds and certain other funds distributed through Franklin Distributors, LLC, the Fund's distributor. More information about these and other discounts is available from your financial professional and under "Your Account" on page 31 in the Fund's Prospectus and under "Buying and Selling Shares" on page 52 of the Fund's Statement of Additional Information. In addition, more information about sales charge discounts and waivers for purchases of shares through specific financial intermediaries is set forth in Appendix A - "Intermediary Sales Charge Discounts and Waivers" to the Fund's prospectus.

Class A1 shares are only available to existing Class A1 shareholders. Class A1 shares are not available to new investors. If you are a Class A1 shareholder, you may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 in Franklin Templeton funds.

Shareholder Fees

(fees paid directly from your investment)

	Class A		Class A1		Class C		Class R6		Advisor Class
Maximum Sales Charge (Load) Imposed on Purchases (as percentage of offering price)	2.25%		2.25%		None		None		None
Maximum Deferred Sales Charge (Load) (as percentage of the lower of original purchase price or sale proceeds)	None	1	None	1	1.00%		None		None
1.	There is a 1% contingent deferred sales charge that applies to investments of $500,000 ($250,000 effective July 1, 2024) or more (see "Investment of $500,000 or More" under "Choosing a Share Class") and purchases by certain retirement plans without an initial sales charge on shares sold within 18 months of purchase.

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FRANKLIN LOW DURATION U.S. GOVERNMENT SECURITIES FUND
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Annual Fund Operating Expenses

(expenses that you pay each year as a percentage of the value of your investment)

	Class A		Class A1		Class C		Class R6		Advisor Class
Management fees	0.50%		0.50%		0.50%		0.50%		0.50%
Distribution and service (12b-1) fees	0.25%		0.10%		0.65%		None		None
Other expenses	0.25%		0.25%		0.25%		0.16%		0.25%
Acquired fund fees and expenses	0.01%		0.01%		0.01%		0.01%		0.01%
Total annual Fund operating expenses1	1.01%		0.86%		1.41%		0.67%		0.76%
Fee waiver and/or expense reimbursement2	-0.16%		-0.16%		-0.16%		-0.10%		-0.16%
Total annual Fund operating expenses after fee waiver and/or expense reimbursement	0.85%		0.70%		1.25%		0.57%		0.60%

¹ Total annual Fund operating expenses differ from the ratio of expenses to average net assets shown in the Financial Highlights, which reflect the operating expenses of the Fund and do not include acquired fund fees and expenses.

² The investment manager has agreed to waive fees and/or reimburse operating expenses (excluding Rule 12b-1 fees, acquired fund fees and expenses, and certain non-routine expenses or costs, such as those relating to litigation, indemnification, reorganizations and liquidations) for the Fund so that the ratio of total annual fund operating expenses will not exceed 0.58% for each share class. The investment manager has also agreed to reduce its fees to reflect reduced services resulting from the Fund's investments in Franklin Templeton affiliated funds. In addition, transfer agency fees on Class R6 shares of the Fund have been capped so that transfer agency fees for that class do not exceed 0.03%. These arrangements are expected to continue until February 28, 2025. During the terms, the fee waiver and expense reimbursement agreements may not be terminated or amended without approval of the board of trustees except to add series or classes, to reflect the extension of termination dates or to lower the waiver and expense limitation (which would result in lower fees for shareholders).

Example

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of the period. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. The Example reflects adjustments made to the Fund's operating expenses due to the fee waivers and/or expense reimbursements by management for the 1 Year numbers only. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

			1 Year		3 Years		5 Years		10 Years
Class A		$310		$524		$755		$1,420
Class A1		$295		$477		$675		$1,247
Class C		$227		$430		$756		$1,568
Class R6		$58		$204		$363		$824
Advisor Class		$61		$226		$406		$927
If you do not sell your shares:
Class C		$127		$430		$756		$1,568

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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 Fund shares are held in a taxable account. These costs, which are not reflected in annual Fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 23.44% of the average value of its portfolio.

Principal Investment Strategies

Under normal market conditions, the Fund invests at least 80% of its net assets in "U.S. government securities." "U.S. government securities" include fixed-rate mortgage securities and adjustable-rate mortgage securities (ARMS) and other mortgage-backed securities, including collateralized mortgage obligations (CMOs), which are issued or guaranteed by the U.S. government, its agencies or instrumentalities, including government-sponsored entities. The Fund also invests in direct obligations of the U.S. government, such as Treasury bills, bonds or notes, or its agencies instrumentalities or sponsored enterprises.

The Fund currently targets an estimated portfolio duration of 1 to 3.5 years. In comparison to maturity (which is the date on which a debt instrument ceases and the issuer is obligated to repay the principal amount), duration is a measure of the expected price volatility of a debt instrument as a result of changes in market rates of interest, based on the weighted average timing of the instrument's expected principal and interest payments and other factors.

Mortgage-backed securities represent an interest in a pool of mortgage loans made by banks and other financial institutions to finance purchases of homes, commercial buildings and other real estate. As the underlying mortgage loans are paid off, investors receive periodic principal and interest payments as well as any unscheduled principal prepayments on the underlying mortgage loans. The mortgage-backed securities purchased by the Fund may include bonds and notes issued or guaranteed by U.S. government-sponsored entities, such as the Federal National Mortgage Association (Fannie Mae) and the Federal Home Loan Mortgage Corporation (Freddie Mac) and by the Government National Mortgage Association (Ginnie Mae). The Fund currently focuses on mortgage-backed securities issued or guaranteed by Fannie Mae and Freddie Mac.

Government agency or instrumentality issues have different levels of credit support. Ginnie Mae pass-through mortgage certificates are backed by the full faith and credit of the U.S. government. U.S. government-sponsored entities, such as Fannie Mae and Freddie Mac, may be chartered by Acts of Congress, but

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FRANKLIN LOW DURATION U.S. GOVERNMENT SECURITIES FUND
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their securities are neither issued nor guaranteed by the U.S. government. Although the U.S. government has provided financial support to Fannie Mae and Freddie Mac, no assurance can be given that the U.S. government will continue to do so. Accordingly, securities issued by Fannie Mae and Freddie Mac may involve a greater risk of non-payment of principal and interest. Investors should remember that guarantees of timely repayment of principal and interest do not apply to the market prices and yields of the securities or to the net asset value or performance of the Fund, which will vary with changes in interest rates and other market conditions.

To pursue its investment goal, the Fund may invest in certain interest rate-related derivative transactions, such as interest rate futures contracts and options on interest rate/bond futures. The use of these derivative transactions may allow the Fund to obtain net long or short exposures to selected interest rates or durations. These derivatives may be used to hedge risks associated with the Fund's other portfolio investments and to manage the duration of the Fund's portfolio.

The Fund may invest up to 20% of its net assets in other securities, including Asset Backed Securities (ABS) and non-agency CMOs, issued by a private entity.

Principal Risks

You could lose money by investing in the Fund. Mutual fund shares are not deposits or obligations of, or guaranteed or endorsed by, any bank, and are not insured by the Federal Deposit Insurance Corporation, the Federal Reserve Board, or any other agency of the U.S. government.

Interest Rate: When interest rates rise, debt security prices generally fall. The opposite is also generally true: debt security prices rise when interest rates fall. Interest rate changes are influenced by a number of factors, including government policy, monetary policy, inflation expectations, perceptions of risk, and supply of and demand for bonds. In general, securities with longer maturities or durations are more sensitive to interest rate changes.

Prepayment: Prepayment risk occurs when a debt security can be repaid in whole or in part prior to the security's maturity and the Fund must reinvest the proceeds it receives, during periods of declining interest rates, in securities that pay a lower rate of interest. Also, if a security has been purchased at a premium, the value of the premium would be lost in the event of prepayment. Prepayments generally increase when interest rates fall.

Adjustable Rate Securities: Because changes in interest rates on adjustable rate securities may lag behind changes in market rates, the value of such securities may decline during periods of rising interest rates until their interest rates reset to market rates. During periods of declining interest rates, because the interest rates

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on adjustable rate securities generally reset downward, their market value is unlikely to rise to the same extent as the value of comparable fixed rate securities.

Mortgage Securities: Mortgage securities differ from conventional debt securities because principal is paid back periodically over the life of the security rather than at maturity. The Fund may receive unscheduled payments of principal due to voluntary prepayments, refinancings or foreclosures on the underlying mortgage loans. Because of prepayments, mortgage securities may be less effective than some other types of debt securities as a means of "locking in" long-term interest rates and may have less potential for capital appreciation during periods of falling interest rates. A reduction in the anticipated rate of principal prepayments, especially during periods of rising interest rates, may increase or extend the effective maturity and duration of mortgage securities, making them more sensitive to interest rate changes, subject to greater price volatility, and more susceptible than some other debt securities to a decline in market value when interest rates rise.

Extension: Some debt securities, particularly mortgage-backed securities, are subject to the risk that the debt security's effective maturity is extended because calls or prepayments are less or slower than anticipated, particularly when interest rates rise. The market value of such security may then decline and become more interest rate sensitive.

Market: The market values of securities or other investments owned by the Fund will go up or down, sometimes rapidly or unpredictably. The market value of a security or other investment may be reduced by market activity or other results of supply and demand unrelated to the issuer. This is a basic risk associated with all investments. When there are more sellers than buyers, prices tend to fall. Likewise, when there are more buyers than sellers, prices tend to rise.

Income: The Fund's distributions to shareholders may decline when prevailing interest rates fall, when the Fund experiences defaults on debt securities it holds or when the Fund realizes a loss upon the sale of a debt security.

Credit: An issuer of debt securities may fail to make interest payments or repay principal when due, in whole or in part. Changes in an issuer's financial strength or in a security's or government's credit rating may affect a security's value. While securities issued by Ginnie Mae are backed by the full faith and credit of the U.S. government, not all securities of the various U.S. government agencies are, including those of Fannie Mae and Freddie Mac. Accordingly, securities issued by Fannie Mae and Freddie Mac may involve a risk of non-payment of principal and interest.

Derivative Instruments: The performance of derivative instruments depends largely on the performance of an underlying instrument, such as a security, interest

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rate or index, and such instruments often have risks similar to their underlying instrument, in addition to other risks. Derivative instruments involve costs and can create economic leverage in the Fund's portfolio which may result in significant volatility and cause the Fund to participate in losses (as well as gains) in an amount that exceeds the Fund's initial investment. Other risks include illiquidity, mispricing or improper valuation of the derivative instrument, and imperfect correlation between the value of the derivative and the underlying instrument so that the Fund may not realize the intended benefits. When a derivative is used for hedging, the change in value of the derivative may also not correlate specifically with the security, interest rate, index or other risk being hedged. With over-the-counter derivatives, there is the risk that the other party to the transaction will fail to perform.

Management: The Fund is subject to management risk because it is an actively managed investment portfolio. The Fund's investment manager applies investment techniques and risk analyses in making investment decisions for the Fund, but there can be no guarantee that these decisions will produce the desired results.

Cybersecurity: 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 investment manager, and/or their service providers (including, but not limited to, Fund accountants, 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 investment manager has 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 investment manager. Cybersecurity incidents may result in financial losses to the Fund and its shareholders, and substantial costs may be incurred in an effort to prevent or mitigate 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.

Because technology is frequently changing, new ways to carry out cyber attacks are always developing. Therefore, there is a chance that some risks have not been identified or prepared for, or that an attack may not be detected, which puts limitations on the Fund's ability to plan for or respond to a cyber attack. Like other funds and business enterprises, the Fund, the investment manager, and their service providers are subject to the risk of cyber incidents occurring from time to time.

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FRANKLIN LOW DURATION U.S. GOVERNMENT SECURITIES FUND
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Performance

The following 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 A shares. The table shows how the Fund's average annual returns for 1 year, 5 years, 10 years or since inception, as applicable, compared with those of a broad measure of market performance. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. You can obtain updated performance information at www.franklintempleton.com or by calling (800) DIAL BEN/342-5236.

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

Class A Annual Total Returns

Best Quarter:	2023, Q4	2.43%
Worst Quarter:	2020, Q1	-1.51%

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FRANKLIN LOW DURATION U.S. GOVERNMENT SECURITIES FUND
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Average Annual Total Returns

(figures reflect sales charges)

For periods ended December 31, 2023

		1 Year		5 Years		10 Years
Franklin Low Duration U.S. Government Securities Fund - Class A
	Return before taxes		1.65%		0.25%		0.21%
	Return after taxes on distributions		0.16%		-0.63%		-0.57%
	Return after taxes on distributions and sale of Fund shares		0.95%		-0.18%		-0.18%
Franklin Low Duration U.S. Government Securities Fund - Class A1		1.93%		0.40%		0.36%
Franklin Low Duration U.S. Government Securities Fund - Class C		2.68%		0.34%		0.05%
Franklin Low Duration U.S. Government Securities Fund - Class R6		4.37%		1.08%		0.81%
Franklin Low Duration U.S. Government Securities Fund - Advisor Class		4.35%		0.97%		0.69%
Bloomberg US Government Index: 1-3 Year Component (index reflects no deduction for fees, expenses or taxes)		4.32%		1.28%		1.05%

Historical performance for Class A1 shares prior to their inception is based on the performance of Class A shares.

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

Investment Manager

Franklin Advisers, Inc. (Advisers or investment manager)

Portfolio Managers

Paul Varunok
Senior Vice President of Advisers and portfolio manager of the Fund since 2003.

Neil Dhruv
Vice President of Advisers and portfolio manager of the Fund since 2023.

Purchase and Sale of Fund Shares

You may purchase or redeem shares of the Fund on any business day online through our website at franklintempleton.com, by mail (Franklin Templeton Investor Services, P.O. Box 997152, Sacramento, CA 95899-7152), or by telephone at (800) 632-2301. For Class A, A1 and C, the minimum initial purchase for most accounts is $1,000 (or $25 under an automatic investment plan). Class R6 and

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FRANKLIN LOW DURATION U.S. GOVERNMENT SECURITIES FUND
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Advisor Class are only available to certain qualified investors and the minimum initial investment will vary depending on the type of qualified investor, as described under "Your Account - Choosing a Share Class - Qualified Investors - Class R6" and "- Advisor Class" in the Fund's prospectus. There is no minimum investment for subsequent purchases.

Taxes

The Fund's distributions are generally taxable to you as ordinary income, capital gains, or some combination of both, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or an individual retirement account, in which case your distributions would generally be taxed when withdrawn from the tax-advantaged account.

Payments to Broker-Dealers and Other Financial Intermediaries

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

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	Franklin Distributors, LLC One Franklin Parkway San Mateo, CA 94403-1906 franklintempleton.com Franklin Low Duration U.S. Government Securities Fund

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