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Short Duration High Yield Fund

Short Duration High Yield Fund

INVESTMENT OBJECTIVE

The Fund’s investment objective is to seek a high current income and the opportunity for capital appreciation to produce a high total return.

FEES AND EXPENSES

This 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 certain members of your family invest, or agree to invest in the future, at least $100,000 in the Lord Abbett Family of Funds. More information about these and other discounts is available from your financial professional and in “Sales Charge Reductions and Waivers” on page 60 of the prospectus, Appendix A to the prospectus, titled “Intermediary-Specific Sales Charge Reductions and Waivers,” and “Purchases, Redemptions, Pricing, and Payments to Dealers” on page 9-1 of Part II of the statement of additional information (“SAI”).

Shareholder Fees (Fees paid directly from your investment)

Shareholder Fees - Short Duration High Yield Fund		Class A		Class C		Class F	Class F3	Class I	Class R2	Class R3	Class R4	Class R5	Class R6
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	[1]	2.25%		none		none	none	none	none	none	none	none	none
Maximum Deferred Sales Charge (Load) (as a percentage of offering price or redemption proceeds, whichever is lower)	[1]	none	[2]	1.00%	[3]	none	none	none	none	none	none	none	none

Annual Fund Operating Expenses (Expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses - Short Duration High Yield Fund		Class A	Class C		Class F		Class F3	Class I	Class R2	Class R3		Class R4		Class R5		Class R6
Management Fees		0.45%	0.45%		0.45%		0.45%	0.45%	0.45%	0.45%		0.45%		0.45%		0.45%
Distribution and Service (12b-1) Fees		0.20%	1.00%	[1]	0.10%		none	none	0.60%	0.50%		0.25%		none		none
Other Expenses		3.30%	3.30%		3.30%		3.23%	3.30%	3.30%	3.30%		3.30%		3.30%		3.23%
Total Annual Fund Operating Expenses		3.95%	4.75%		3.85%		3.68%	3.75%	4.35%	4.25%	[2]	4.00%	[2]	3.75%	[2]	3.68%
Fee Waiver and/or Expense Reimbursement	[3]	(3.24%)	(3.24%)		(3.34%)	[4]	(3.24%)	(3.24%)	(3.24%)	(3.24%)		(3.24%)		(3.24%)		(3.24%)
Total Annual Fund Operating Expenses After Fee Waiver and/or Expense Reimbursement	[3]	0.71%	1.51%		0.51%		0.44%	0.51%	1.11%	1.01%		0.76%		0.51%		0.44%

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 those periods. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same, giving effect to the fee waiver and expense reimbursement arrangement described above. Class C shares automatically convert to Class A shares after eight years. The expense example for Class C shares for the ten-year period reflects the conversion to Class A shares. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

If Shares Are Redeemed

Expense Example - Short Duration High Yield Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class A	296	1,110	1,941	4,096
Class C	254	1,139	2,130	4,466
Class F	52	866	1,699	3,866
Class F3	45	825	1,625	3,721
Class I	52	846	1,659	3,783
Class R2	113	1,023	1,944	4,301
Class R3	103	994	1,898	4,217
Class R4	78	920	1,779	4,003
Class R5	52	846	1,659	3,783
Class R6	45	825	1,625	3,721

If Shares Are Not Redeemed

Expense Example No Redemption - Short Duration High Yield Fund - USD ($)	1 Year	3 Years	5 Years	10 Years
Class A	296	1,110	1,941	4,096
Class C	154	1,139	2,130	4,466
Class F	52	866	1,699	3,866
Class F3	45	825	1,625	3,721
Class I	52	846	1,659	3,783
Class R2	113	1,023	1,944	4,301
Class R3	103	994	1,898	4,217
Class R4	78	920	1,779	4,003
Class R5	52	846	1,659	3,783
Class R6	45	825	1,625	3,721

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 the annual fund operating expenses or in the example, affect the Fund’s performance. During the period from April 22, 2020 (commencement of operations) to July 31, 2020, the Fund’s portfolio turnover rate was 27% of the average value of its portfolio.

PRINCIPAL INVESTMENT STRATEGIES

Under normal conditions, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in lower-rated debt securities (commonly referred to as “high-yield” or “junk” bonds). Debt securities in which the Fund may invest include bonds, debentures, notes, commercial paper, corporate debt securities, floating or adjustable rate loans (including bridge loans, novations, assignments, and participations), which may include “covenant-lite” obligations, securities that are convertible into common stock or have warrants to purchase common stock, and other similar types of debt obligations.

High-yield debt securities are debt securities that are rated BB/Ba or lower by an independent rating agency, or are unrated but determined by Lord Abbett to be of comparable quality. The Fund may invest in debt securities of any credit quality, including defaulted securities (i.e., bonds on which the issuer has not paid principal or interest on time) and securities of issuers that are or may become involved in reorganizations, financial restructurings, or bankruptcy (commonly referred to as “distressed debt”).

The Fund may invest up to 20% of its net assets in foreign securities (including emerging market securities and American Depositary Receipts (“ADRs”), and other similar depositary receipts). The Fund defines foreign securities as securities of non-U.S. issuers that are denominated in non-U.S. currencies.

The Fund attempts to manage interest rate risk through its management of the average duration of the securities it holds in its portfolio. Normally, the Fund will seek to maintain a weighted average duration range of three years or less. Subject to the foregoing, the Fund does not have any maturity or duration restrictions and may invest in securities of any maturity or duration. The duration of a security takes into account the pattern of all expected payments of interest and principal on the security over time, including how these payments are affected by changes in interest rates. The longer a portfolio’s duration, the more sensitive it is to interest rate risk. The shorter a portfolio’s duration, the less sensitive it is to interest rate risk. Because the Fund primarily invests in short duration bonds, it is less sensitive to interest rate changes than a fund that focuses on longer duration bonds.

Currently, the Fund expects to invest in derivatives consisting principally of futures, forwards, options, and swaps. The Fund may use derivatives to seek to enhance returns, to attempt to hedge some of its investment risk, to manage portfolio duration, as a substitute for holding the underlying asset on which the derivative instrument is based, or for cash management purposes. For example, the Fund may invest in U.S. Treasury futures or sell U.S. Treasury futures short to adjust the Fund’s exposure to the direction of interest rates, or for other portfolio management reasons. The market value of derivatives providing economic exposure substantially similar to the securities referenced in the Fund’s 80% policy, as described above, will be counted for purposes of measuring the Fund’s compliance with its 80% policy.

The Fund’s portfolio management team believes high total return (current income and capital appreciation) may be derived from an actively-managed, diversified portfolio of investments. In addition to seeking current income, the portfolio management team seeks to invest across the ratings spectrum, particularly in lower-rated debt securities. The portfolio management team seeks to purchase lower-rated securities that it believes will experience declining credit risk, allowing the securities potentially to generate higher returns. The portfolio management team selects securities using a bottom-up analysis of an issuer’s management quality, credit, and relative market position, and industry dynamics, as well as an evaluation of conditions within the broader economy. The portfolio management team attempts to reduce investment risk through portfolio diversification, credit analysis, and attention to current developments and trends in interest rates and economic conditions. The investment team may also consider the risks and return potential presented by environmental, social, and governance (ESG) factors in investment decisions. The Fund may engage in active and frequent trading of its portfolio securities.

The Fund may sell a security when the Fund believes the security is less likely to benefit from the current market and economic environment, or shows signs of deteriorating fundamentals, among other reasons. The Fund may deviate from the investment strategy described above for temporary defensive purposes. The Fund may miss certain investment opportunities if defensive strategies are used and thus may not achieve its investment objective.

PRINCIPAL RISKS

As with any investment in a mutual fund, investing in the Fund involves risk, including the risk that you may receive little or no return on your investment. When you redeem your shares, they may be worth more or less than what you paid for them, which means that you may lose a portion or all of the money you invested in the Fund. The principal risks of investing in the Fund, which could adversely affect its performance, include:

● Portfolio Management Risk: If the strategies used and investments selected by the Fund’s portfolio management team fail to produce the intended result, the Fund may suffer losses or underperform other funds with the same investment objective or strategies, even in a favorable market.

● Market Risk: The market values of securities will fluctuate, sometimes sharply and unpredictably, based on overall economic conditions, governmental actions or intervention, market disruptions caused by trade disputes or other factors, political developments, and other factors. Prices of equity securities tend to rise and fall more dramatically than those of debt securities.

● New Fund Risk: The Fund is newly organized. There can be no assurance that the Fund will reach or maintain a sufficient asset size to effectively implement its investment strategy. In addition, until the Fund achieves sufficient scale, a Fund shareholder may experience proportionally higher Fund expenses than would be experienced by shareholders of a fund with a larger asset base.

● Fixed Income Securities Risk: The Fund is subject to the general risks and considerations associated with investing in debt securities, including the risk that issuers will fail to make timely payments of principal or interest or default altogether. Lower-rated securities in which the Fund may invest may be more volatile and may decline more in price in response to negative issuer developments or general economic news than higher rated securities. In addition, as interest rates rise, the Fund’s investments typically will lose value.

● High Yield Securities Risk: High yield securities (commonly referred to as “junk” bonds) typically pay a higher yield than investment grade securities, but may have greater price fluctuations and have a higher risk of default than investment grade securities. The market for high yield securities may be less liquid due to such factors as interest rate sensitivity, negative perceptions of the junk bond markets generally, and less secondary market liquidity. This may make such securities more difficult to sell at an acceptable price, especially during periods of financial distress, increased market volatility, or significant market decline.

● Credit Risk: Debt securities are subject to the risk that the issuer or guarantor of a security may not make interest and principal payments as they become due or may default altogether. In addition, if the market perceives a deterioration in the creditworthiness of an issuer, the value and liquidity of securities issued by

that issuer may decline. To the extent that the Fund holds below investment grade securities, these risks may be heightened. Insured debt securities have the credit risk of the insurer in addition to the credit risk of the underlying investment being insured.

● Interest Rate Risk: As interest rates rise, prices of bonds (including tax-exempt bonds) generally fall, typically causing the Fund’s investments to lose value. Additionally, rising interest rates or lack of market participants may lead to decreased liquidity in fixed income markets. Interest rate changes generally have a more pronounced effect on the market value of fixed-rate instruments, such as corporate bonds, than they have on floating rate instruments, and typically have a greater effect on the price of fixed income securities with longer durations. A wide variety of market factors can cause interest rates to rise, including central bank monetary policy, rising inflation, and changes in general economic conditions. To the extent the Fund invests in floating rate instruments, changes in short-term market interest rates may affect the yield on those investments. If short-term market interest rates fall, the yield on the Fund’s shares will also fall. Conversely, when short-term market interest rates rise, because of the lag between changes in such short- term rates and the resetting of the floating rates on the floating rate debt in the Fund’s portfolio, the impact of rising rates may be delayed. To the extent the Fund invests in fixed rate instruments, fluctuations in the market price of such investments may not affect interest income derived from those instruments, but may nonetheless affect the Fund’s NAV, especially if the instrument has a longer maturity. Substantial increases in interest rates may cause an increase in issuer defaults, as issuers may lack resources to meet higher debt service requirements.

● Foreign Currency Risk: Investments in securities denominated in foreign currencies are subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedged positions, that the U.S. dollar will decline in value relative to the currency being hedged. Foreign currency exchange rates may fluctuate significantly over short periods of time.

● Liquidity/Redemption Risk: The Fund may lose money when selling securities at inopportune times to fulfill shareholder redemption requests. The risk of loss may increase depending on the size and frequency of redemption requests, whether the redemption requests occur in times of overall market turmoil or declining prices, and whether the securities the Fund intends to sell have decreased in value or are illiquid. The Fund may be less able to sell illiquid securities at its desired time or price. It may be more difficult for the Fund to value its investments in illiquid securities than more liquid securities.

● Convertible Securities Risk: Convertible securities are subject to the risks affecting both equity and fixed income securities, including market, credit, liquidity, and interest rate risk. Convertible securities tend to be more volatile than other fixed income securities, and the markets for convertible securities may be less liquid than markets for common stocks or bonds. To the extent that

the Fund invests in convertible securities and the investment value of the convertible security is greater than its conversion value, its price will likely increase when interest rates fall and decrease when interest rates rise. If the conversion value exceeds the investment value, the price of the convertible security will tend to fluctuate directly with the price of the underlying equity security. A significant portion of convertible securities have below investment grade credit ratings and are subject to increased credit and liquidity risks.

● Industry and Sector Risk: Although the Fund does not employ an industry or sector focus, its exposure to specific industries or sectors will increase from time to time based on the portfolio management team’s perception of investment opportunities. If the Fund overweights a single industry or sector relative to its benchmark index, the Fund will face an increased risk that the value of its portfolio will decrease because of events disproportionately affecting that industry or sector. Furthermore, investments in particular industries or sectors may be more volatile than the broader market as a whole.

● Foreign and Emerging Market Company Risk: Investments in foreign companies and in U.S. companies with economic ties to foreign markets generally involve special risks that can increase the likelihood that the Fund will lose money. For example, as compared with companies organized and operated in the U.S., these companies may be more vulnerable to economic, political, and social instability and subject to less government supervision, lack of transparency, inadequate regulatory and accounting standards, and foreign taxes. In addition, the securities of foreign companies also may be subject to inadequate exchange control regulations, the imposition of economic sanctions or other government restrictions, higher transaction and other costs, reduced liquidity, and delays in settlement to the extent they are traded on non-U.S. exchanges or markets. Foreign company securities also include ADRs. ADRs may be less liquid than the underlying shares in their primary trading market. Foreign securities also may subject the Fund’s investments to changes in currency exchange rates. Emerging market securities generally are more volatile than other foreign securities, and are subject to greater liquidity, regulatory, and political risks. Investments in emerging markets may be considered speculative and generally are riskier than investments in more developed markets because such markets tend to develop unevenly and may never fully develop. Emerging markets are more likely to experience hyperinflation and currency devaluations. Securities of emerging market companies may have far lower trading volumes and less liquidity than securities of issuers in developed markets. Companies with economic ties to emerging markets may be susceptible to the same risks as companies organized in emerging markets.

● Loan Risk: Investments in floating or adjustable rate loans are subject to increased credit and liquidity risks. Loan prices also may be adversely affected by supply-demand imbalances caused by conditions in the loan market or related markets. Below investment grade loans, like high-yield debt securities, or junk bonds, usually are more credit sensitive than interest rate sensitive,

although the value of these instruments may be affected by interest rate swings in the overall fixed income market. Loans may be subject to structural subordination and may be subordinated to other obligations of the borrower or its subsidiaries.

● “Covenant-lite” Obligations Risk: The Fund may invest in, or obtain exposure to, obligations that may be “covenant-lite,” which means such obligations lack certain financial maintenance covenants. While these loans may still contain other collateral protections, a covenant-lite loan is riskier because it does not require the borrower to provide affirmation that certain specific financial tests have been satisfied. Should a loan held by the Fund begin to deteriorate in quality, the Fund’s ability to negotiate with the borrower may be delayed under a covenant-lite loan compared to a loan with full maintenance covenants. This may in turn delay the Fund’s ability to seek to recover its investment.

● Defaulted Bonds Risk: Defaulted bonds are subject to greater risk of loss of income and principal than securities of issuers whose debt obligations are being met. Defaulted bonds are considered speculative with respect to the issuer’s ability to make interest payments and pay its obligations in full. The repayment of defaulted bonds therefore is subject to significant uncertainties, and in some cases, there may be no recovery of repayment. Defaulted bonds may be repaid only after lengthy workout or bankruptcy proceedings, during which the issuer may not make any interest or other payments. Workout or bankruptcy proceedings typically result in only partial recovery of cash payments or an exchange of the defaulted bond for other securities of the issuer or its affiliates, which securities may in turn be illiquid, subject to restrictions on resale, or speculative.

● Distressed Debt Risk: Distressed bonds are speculative and involve substantial risks in addition to the risks of investing in high-yield debt securities. The Fund is subject to an increased risk that it may lose a portion or all of its investment in the distressed debt and may incur higher expenses trying to protect its interests in distressed debt. The prices of distressed bonds are likely to be more sensitive to adverse economic changes or individual issuer developments than the prices of higher rated securities. During an economic downturn or substantial period of rising interest rates, distressed debt issuers may experience financial stress that would adversely affect their ability to service their principal and interest payment obligations, to meet their projected business goals, or to obtain additional financing. Moreover, it is unlikely that a liquid market will exist for the Fund to sell its holdings in distressed debt securities.

● Derivatives Risk: The risks associated with derivatives may be different from and greater than the risks associated with directly investing in securities and other investments. Derivatives may increase the Fund’s volatility and reduce its returns. The risks associated with derivatives include, among other things, the following:

● The risk that the value of a derivative may not correlate with the value of the underlying asset, rate, or index in the manner anticipated by the portfolio management team and may be more sensitive to changes in economic or market conditions than anticipated.

● Derivatives may be difficult to value, especially under stressed or unforeseen market conditions.

● The risk that the counterparty may fail to fulfill its contractual obligations under the derivative contract. Central clearing of derivatives is intended to decrease counterparty risk but does not eliminate it.

● The Fund may be required to segregate permissible liquid assets to cover its obligations under these transactions and may have to liquidate positions before it is desirable to do so to fulfill its segregation requirements.

● The risk that there may not be a liquid secondary trading market for the derivative, or that the Fund may otherwise be unable to sell or otherwise close a derivatives position when desired, exposing the Fund to additional losses.

● Because derivatives generally involve a small initial investment relative to the risk assumed (known as leverage), derivatives can magnify the Fund’s losses and increase its volatility.

● The Fund’s use of derivatives may affect the amount, timing, and character of distributions, and may cause the Fund to realize more short-term capital gain and ordinary income than if the Fund did not use derivatives.

Derivatives may not perform as expected and the Fund may not realize the intended benefits. Whether the Fund’s use of derivatives is successful will depend on, among other things, the portfolio managers’ ability to correctly forecast market movements and other factors. If the portfolio managers incorrectly forecast these and other factors, the Fund’s performance could suffer. In addition, given their complexity, derivatives are subject to the risk that improper or misunderstood documentation may expose the Fund to losses.

● High Portfolio Turnover Risk: High portfolio turnover may result in increased transaction costs, reduced investment performance, and higher taxes resulting from increased realized capital gains, including short-term capital gains taxable as ordinary income when distributed to shareholders.

An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. For more information on the principal risks of the Fund, please see the “More Information About the Funds – Principal Risks” section in the prospectus.

PERFORMANCE

This prospectus does not show performance information for the Fund because the Fund is recently organized and has not completed a full calendar year of

performance since it commenced operations on April 22, 2020. Performance for the Fund, which provides some indication of the risks of investing in the Fund, will vary from year to year. Updated performance information is available at www.lordabbett.com or by calling 888-522-2388.

[1] A shareholder transacting in share classes without a front-end sales charge may be required to pay a commission to its financial intermediary. Please contact your financial intermediary for more information about whether such a commission may apply to your transaction.

[2] A contingent deferred sales charge (“CDSC”) of 1.00% may be assessed on certain Class A shares purchased or acquired without a sales charge if they are redeemed before the first day of the month of the one-year anniversary of the purchase.

[3] A CDSC of 1.00% may be assessed on Class C shares if they are redeemed before the first anniversary of their purchase.

[1] The 12b-1 fee the Fund will pay on Class C shares will be a blended rate calculated based on (i) 1.00% of the Fund’s average daily net assets attributable to shares held for less than one year and (ii) 0.80% of the Fund’s average daily net assets attributable to shares held for one year or more. All Class C shareholders of the Fund will bear 12b-1 fees at the same rate.

[2] These amounts have been updated from fiscal year amounts to reflect current fees and expenses.

[3] For the period from April 22, 2020  through November 30, 2021, Lord, Abbett & Co. LLC (“Lord Abbett”) has contractually agreed to waive its fees and reimburse expenses to the extent necessary to limit total net annual operating expenses, excluding any applicable 12b-1 fees, acquired fund fees and expenses, interest-related expenses, taxes, expenses related to litigation and potential litigation, and extraordinary expenses, to an annual rate of 0.44% for each of Class F3 and R6 shares and to an annual rate of 0.51% for each other class. This agreement may be terminated only by the Fund’s Board of Trustees.

[4] For the period from April 22, 2020 through November 30, 2021, Lord Abbett Distributor LLC (“Lord Abbett Distributor”) has contractually agreed to waive the Fund’s 0.10% Rule 12b-1 fee for Class F shares. This agreement may be terminated only by the Fund’s Board of Trustees.