SUMMARY PROSPECTUS

Franklin
Convertible Securities Fund

Franklin
Investors Securities Trust

March 1, 2019

Class A	Class C	Class R6	Advisor Class
FISCX	FROTX	FCSKX	FCSZX

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 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 prospectus@franklintempleton.com. The Fund's prospectus and statement of additional information, both dated March 1, 2019, as may be supplemented, are all incorporated by reference into this Summary Prospectus.

Internet Delivery of Fund Reports Unless You Request Paper Copies: Effective January 1, 2021, as permitted by the SEC, paper copies of the Fund's shareholder reports will no longer be sent by mail, unless you specifically request them from the Fund or your financial intermediary. Instead, the reports will be made available on a website, and you will be notified by mail each time a report is posted and provided with a website link to access the report.

If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. If you have not signed up for electronic delivery, we would encourage you to join fellow shareholders who have. You may elect to receive shareholder reports and other communications electronically from the Fund by calling (800) 632-2301 or by contacting your financial intermediary.

You may elect to continue to receive paper copies of all your future shareholder reports free of charge by contacting your financial intermediary or, if you invest directly with a Fund, calling (800) 632-2301 to let the Fund know of your request. Your election to receive reports in paper will apply to all funds held in your account.

Franklin Convertible Securities Fund

Effective on August 29, 2018, the Fund was closed to new investors. Existing investors who had an open and funded account on August 29, 2018 can continue to invest through exchanges and additional purchases. The following categories of investors can continue to open new accounts in the Fund: (1) clients of discretionary investment allocation programs where such programs had investments in the Fund prior to the close of market on August 29, 2018; (2) employer sponsored retirement plans or benefit plans and their participants where the Fund was available to participants in such plans prior to the close of market on August 29, 2018; (3) employer sponsored retirement plans or benefit plans that approved the Fund as an investment option prior to the close of market on August 29, 2018, but that have not opened an account as of that date, provided that the initial account is opened with the Fund on or prior to February 28, 2019; (4) other Franklin Templeton Funds and Funds for which Franklin Templeton investment managers provide advisory or sub-advisory services upon prior approval by the Fund’s investment manager; (5) trustees and officers of the Trust; and (6) members of the Fund’s portfolio management team. The Fund may restrict, reject or cancel any purchase order, including an exchange request, and reserves the right to modify this policy at any time.

Investment Goal

To maximize total return, consistent with reasonable risk, by seeking to optimize capital appreciation and high current income under varying market conditions.

Fees and Expenses of the Fund

These tables describe the fees and expenses that you may pay if you buy and hold shares of the Fund. 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 $50,000 in Franklin Templeton funds. More information about these and other discounts is available from your financial professional and under “Your Account” on page 105 in the Fund's Prospectus and under “Buying and Selling Shares” on page 85 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.

Please note that the tables and examples below do not reflect any transaction fees that may be charged by financial intermediaries, or commissions that a shareholder may be required to pay directly to its financial intermediary when buying or selling Class R6 or Advisor Class shares.

Shareholder Fees (fees paid directly from your investment)

	Class A	Class C¹	Class R6	Advisor Class
Maximum Sales Charge (Load) Imposed on Purchases (as percentage of offering price)	5.50%	None	None	None
Maximum Deferred Sales Charge (Load) (as percentage of the lower of original purchase price or sale proceeds)	None²	1.00%	None	None

1. Effective October 5, 2018, Class C shares of the Fund convert automatically to Class A shares of the Fund on a monthly basis in the month of, or the month following, the 10-year anniversary of the Class C shares’ purchase date. Such conversions are on the basis of the relative net asset values of the two classes, are not subject to Class A shares’ sales charges and are not expected to be a taxable event for federal income tax purposes. Certain shares that are invested through retirement plans, omnibus accounts or in certain other instances may not automatically convert if the financial intermediary does not have the ability to track purchases to credit individual shareholders’ holding periods. (See “Your Account – Choosing a Share Class – Sales Charges - Class C – Automatic Conversion of Class C Shares to Class A Shares After 10-Year Holding Period” for more information.)

2. There is a 1% contingent deferred sales charge that applies to investments of $1 million or more (see "Investments of $1 Million 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.

Annual Fund Operating Expenses

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

	Class A	Class C	Class R6	Advisor Class
Management fees	0.46%	0.46%	0.46%	0.46%
Distribution and service (12b-1) fees	0.25%	1.00%	None	None
Other expenses¹	0.14%	0.14%	0.09%	0.14%
Acquired fund fees and expenses²	0.02%	0.02%	0.02%	0.02%
Total annual Fund operating expenses	0.87%	1.62%	0.57%	0.62%
Fee waiver and/or expense reimbursement³	-0.02%	-0.02%	-0.06%	-0.02%
Total annual Fund operating expenses after fee waiver and/or expense reimbursement^2,³	0.85%	1.60%	0.51%	0.60%

1. Other expenses of the Fund, except for Class R6 shares, have been restated to exclude non-recurring period expense. If such expenses were included in the table above, other expenses would have been higher. Consequently, the total annual Fund operating expenses differ from the ratio of expenses to average net assets shown in the Financial Highlights.

2. 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.

3. The investment manager has contractually agreed in advance to reduce its fee as a result of the Fund's investment in a Franklin Templeton money fund (acquired fund) for at least one year following the date of this prospectus. In addition, the transfer agent has contractually agreed to cap transfer agency fees for Class R6 shares of the Fund so that transfer agency fees for that class of the Fund do not exceed 0.03% until February 29, 2020. Contractual fee waiver and/or expense reimbursement agreements may not be changed or terminated during the time period set forth 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 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	$ 632	$ 810	$ 1,004	$ 1,563
Class C	$ 263	$ 509	$ 880	$ 1,922
Class R6	$ 52	$ 177	$ 312	$ 708
Advisor Class	$ 61	$ 197	$ 344	$ 773
If you do not sell your shares:
Class C	$ 163	$ 509	$ 880	$ 1,922

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 35.90% 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 convertible securities (and common stock received upon conversion of convertible securities). A convertible security is generally a debt security or preferred stock that may be converted within a specified period of time into common stock of the same or a different issuer. By investing in convertible securities, the Fund seeks the opportunity to participate in the capital appreciation of underlying stocks, while at the same time relying on the fixed income aspect of the convertible securities to provide current income and reduced price volatility, which can limit the risk of loss in a down equity market.

A convertible security shares features of both equity and debt securities. Like an equity security, the value of a convertible security tends to increase as the price of the underlying stock goes up, and to decrease as the price of the underlying stock goes down. Like a debt security, a convertible security provides a fixed income stream and also tends to increase in value when interest rates fall and decrease in value when interest rates rise.

When choosing convertible securities for this Fund, the investment manager attempts to maintain a balance in the portfolio between the equity and debt characteristics of convertible securities with an emphasis on the equity features. The investment manager also considers the company’s long-term earnings, asset value and cash flow potential. Some of the convertible securities in which the Fund may invest have been structured to provide enhanced yield, increased equity exposure, or enhanced downside protection. These securities, generally referred to as enhanced convertible securities, typically provide a benefit to the issuer in exchange for the enhanced features, such as a conversion premium that is paid by the Fund. The Fund may invest in convertible securities of companies of any capitalization size, but generally seeks to make its portfolio representative of the entire convertible securities market.

Convertible securities generally fall within the lower-rated categories as determined by securities rating agencies. Therefore, the Fund may invest up to 100% of its assets in securities that are rated below investment grade; however, the Fund will not invest more than 10% of its assets in non-convertible debt securities rated below B by an independent rating agency such as Standard & Poor's or Moody's Investors Service. The Fund may invest up to 20% of its net assets in other securities, such as common or preferred stocks and non-convertible debt securities. The Fund currently intends to limit its investments in foreign securities to 25% or less of its total assets.

While the Fund does not concentrate in any one industry, from time to time, based on economic conditions, it may make significant investments in certain sectors.

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.

Convertible Securities Convertible securities are subject to the risks of stocks when the underlying stock price is high relative to the conversion price (because more of the security's value resides in the conversion feature) and debt securities when the underlying stock price is low relative to the conversion price (because the conversion feature is less valuable). A convertible security is not as sensitive to interest rate changes as a similar non-convertible debt security, and generally has less potential for gain or loss than the underlying stock.

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 credit rating may affect a security's value.

High-Yield Debt Securities Issuers of lower-rated or “high-yield” debt securities (also known as “junk bonds”) are not as strong financially as those issuing higher credit quality debt securities. High-yield debt securities are generally considered predominantly speculative by the applicable rating agencies as their issuers are more likely to encounter financial difficulties because they may be more highly leveraged, or because of other considerations. In addition, high yield debt securities generally are more vulnerable to changes in the relevant economy, such as a recession or a sustained period of rising interest rates, that could affect their ability to make interest and principal payments when due. The prices of high-yield debt securities generally fluctuate more than those of higher credit quality. High-yield debt securities are generally more illiquid (harder to sell) and harder to value.

Liquidity From time to time, the trading market for a particular security or type of security or other investments in which the Fund invests may become less liquid or even illiquid. Reduced liquidity will have an adverse impact on the Fund’s ability to sell such securities or other investments when necessary to meet the Fund’s liquidity needs, which may arise or increase in response to a specific economic event or because the investment manager wishes to purchase particular investments or believes that a higher level of liquidity would be advantageous. Reduced liquidity will also generally lower the value of such securities or other investments. Market prices for such securities or other investments may be relatively volatile.

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.

Stock prices tend to go up and down more dramatically than those of debt securities. A slower-growth or recessionary economic environment could have an adverse effect on the prices of the various stocks held by the Fund.

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.

Focus To the extent that the Fund focuses on particular countries, regions, industries, sectors or types of investment from time to time, the Fund may be subject to greater risks of adverse developments in such areas of focus than a fund that invests in a wider variety of countries, regions, industries, sectors or investments.

Foreign Securities (non-U.S.) Investing in foreign securities typically involves more risks than investing in U.S. securities, including risks related to currency exchange rates and policies, country or government specific issues, less favorable trading practices or regulation and greater price volatility. Certain of these risks also may apply to securities of U.S. companies with significant foreign operations.

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.

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.

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 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:	Q3'09	17.53%
Worst Quarter:	Q3'11	-16.12%

Average Annual Total Returns
(figures reflect sales charges)

For the periods ended December 31, 2018

	1 Year	5 Years	10 Years
Franklin Convertible Securities Fund - Class A
Return Before Taxes	-1.46%	5.65%	12.09%
Return After Taxes on Distributions	-3.61%	3.67%	10.36%
Return After Taxes on Distributions and Sale of Fund Shares	-0.35%	3.72%	9.32%
Franklin Convertible Securities Fund - Class C	2.49%	6.05%	11.89%
Franklin Convertible Securities Fund - Class R6	4.64%	6.33%¹	—
Franklin Convertible Securities Fund - Advisor Class	4.56%	7.12%	13.01%
ICE BofAML All Alternatives U.S. Convertibles Index (index reflects no deduction for fees, expenses or taxes)	3.45%	5.95%	13.84%

1. Since inception March 4, 2014.

The figures in the average annual total returns table above reflect the Class A maximum front-end sales charge of 5.50%. Prior to September 10, 2018, Class A shares were subject to a maximum front-end sales charge of 5.75%. If the prior maximum front-end sales charge of 5.75% was reflected, performance for Class A in the average annual total returns table would be lower.

Historical performance Advisor Class shares prior to their inception is based on the performance of Class A shares. Advisor Class performance has been adjusted to reflect differences in sales charges and 12b-1 expenses between classes.

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-deferred 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)

Portfolio Managers

Alan E. Muschott, CFA Vice President of Advisers and portfolio manager of the Fund since 2002.

Matthew D. Quinlan Vice President of Advisers and portfolio manager of the Fund since 2007.

Eric Webster, CFA Portfolio Manager of Advisers and portfolio manager of the Fund since 2016.

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 997151, Sacramento, CA 95899-7151), or by telephone at (800) 632-2301. For Class A and C, the minimum initial purchase for most accounts is $1,000 (or $25 under an automatic investment plan). Class R6 and 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-deferred 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-deferred 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.

	Franklin Templeton Distributors, Inc. One Franklin Parkway San Mateo, CA 94403-1906 franklintempleton.com Franklin Convertible Securities Fund

Investment Company Act file #811-04986
© 2019 Franklin Templeton Investments. All rights reserved.
137 PSUM 03/19	00070377