Summary Prospectus by Investment Company - Form 497K

Untitled Document

SUMMARY PROSPECTUS

Lord Abbett Developing Growth Fund

DECEMBER 1, 2024

CLASS/TICKER
CLASS A	LAGWX	CLASS I	LADYX	CLASS R4	LADSX
CLASS C	LADCX	CLASS P	LADPX	CLASS R5	LADTX
CLASS F	LADFX	CLASS R2	LADQX	CLASS R6	LADVX
CLASS F3	LOGWX	CLASS R3	LADRX

Before you invest, you may want to review the Fund's prospectus and statement of additional information, which contain 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 at www.lordabbett.com/documentsandliterature. You can also get this information at no cost by calling 888-522-2388 (Option #2) or by sending an email request to literature@lordabbett.com. The current prospectus and statement of additional information dated December 1, 2024 as may be supplemented from time to time, are incorporated by reference into this summary prospectus.

INVESTMENT OBJECTIVE

The Fund's investment objective is long-term growth of capital through a diversified and actively managed portfolio consisting of developing growth companies, many of which are traded over the counter.

FEES AND EXPENSES

This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts if you and certain members of your family invest, or agree to invest in the future, at least $50,000 in the Lord Abbett Family of Funds. More information about these and other discounts is available from your financial intermediary and in "Sales Charge Reductions and Waivers" on page 34 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(1)	(Fees paid directly from your investment)
Class		A	C	F, F3, I, P, R2, R3, R4, R5, and R6
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	5.75%	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of offering price or redemption proceeds, whichever is lower)	None(2)	1.00%(3)	None

Annual Fund Operating Expenses
(Expenses that you pay each year as a percentage of the value of your investment)
Class	A	C	F	F3	I	P
Management Fees	0.51%	0.51%	0.51%	0.51%	0.51%	0.51%
Distribution and Service (12b-1) Fees	0.25%	1.00%	0.10%	None	None	0.45%
Other Expenses	0.18%	0.18%	0.18%	0.08%	0.18%	0.18%
Total Annual Fund Operating Expenses	0.94%	1.69%	0.79%	0.59%	0.69%	1.14%

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Annual Fund Operating Expenses (continued)
(Expenses that you pay each year as a percentage of the value of your investment)
Class	R2	R3	R4	R5	R6
Management Fees	0.51%	0.51%	0.51%	0.51%	0.51%
Distribution and Service (12b-1) Fees	0.60%	0.50%	0.25%	None	None
Other Expenses	0.18%	0.18%	0.18%	0.18%	0.08%
Total Annual Fund Operating Expenses	1.29%	1.19%	0.94%	0.69%	0.59%

(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 in which the one-year anniversary of the purchase falls.
(3)	A CDSC of 1.00% may be assessed on Class C shares if they are redeemed before the first anniversary of their purchase.

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. 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:

Class	If Shares Are Redeemed	If Shares Are Not Redeemed
	1 Year	3 Years	5 Years	10 Years	1 Year	3 Years	5 Years	10 Years
Class A Shares	$	665	$	857	$	1,065	$	1,663	$	665	$	857	$	1,065	$	1,663
Class C Shares	$	272	$	533	$	918	$	1,799	$	172	$	533	$	918	$	1,799
Class F Shares	$	81	$	252	$	439	$	978	$	81	$	252	$	439	$	978
Class F3 Shares	$	60	$	189	$	329	$	738	$	60	$	189	$	329	$	738
Class I Shares	$	70	$	221	$	384	$	859	$	70	$	221	$	384	$	859
Class P Shares	$	116	$	362	$	628	$	1,386	$	116	$	362	$	628	$	1,386
Class R2 Shares	$	131	$	409	$	708	$	1,556	$	131	$	409	$	708	$	1,556
Class R3 Shares	$	121	$	378	$	654	$	1,443	$	121	$	378	$	654	$	1,443
Class R4 Shares	$	96	$	300	$	520	$	1,155	$	96	$	300	$	520	$	1,155
Class R5 Shares	$	70	$	221	$	384	$	859	$	70	$	221	$	384	$	859
Class R6 Shares	$	60	$	189	$	329	$	738	$	60	$	189	$	329	$	738

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

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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 most recent fiscal year, the Fund's portfolio turnover rate was 122% of the average value of its portfolio.

PRINCIPAL INVESTMENT STRATEGIES

The Fund invests in equity securities of companies that the portfolio management team believes demonstrate above-average, long-term growth potential. The portfolio management team seeks to identify companies that it believes are strongly positioned in the developing growth phase, which it defines as the period of swift development after a company's start-up phase when growth is expected to occur at a rate generally not equaled by established companies in their mature years.

Under normal conditions, the Fund invests at least 65% of its net assets in equity securities of small companies. A small company is defined as a company having a market capitalization at the time of purchase that falls within the market capitalization range of companies in the Russell 2000^® Index.

Equity securities in which the Fund may invest include common stocks, preferred stocks, equity interests in trusts (including real estate investment trusts ("REITs") and privately offered trusts), partnerships, joint ventures, limited liability companies and vehicles with similar legal structures, other instruments convertible or exercisable into the foregoing, and other investments with similar economic characteristics.

The Fund may invest up to 10% of its net assets in securities of foreign companies, including emerging market companies, American Depositary Receipts ("ADRs"), and other similar depositary receipts. In addition to ADRs, the Fund generally defines foreign companies as those whose securities are traded primarily on non-U.S. securities exchanges.

The Fund may engage in active and frequent trading of its portfolio securities.

The investment team may consider the risks and return potential presented by environmental, social, and governance ("ESG") factors in investment decisions. 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

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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.

· Equity Securities Risk: Equity securities, as well as equity-like securities such as convertible debt securities, may experience significant volatility. Such securities may fall sharply in response to adverse events affecting overall markets, a particular industry or sector, or an individual company's financial condition.

· 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 is overweight in 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.

· Mid-Sized and Small Company Risk: Investments in mid-sized and small companies may involve greater risks than investments in larger, more established companies. Securities of mid-sized and small companies tend to be more sensitive to changing economic, market, and industry conditions and tend to be more volatile and less liquid than equity securities of larger companies, especially over the short term. The securities of mid-sized and small companies tend to trade less frequently than those of larger, more established companies, which can adversely affect the pricing of these securities and the ability to sell these securities in the future.

· Growth Investing Risk: Growth stocks typically trade at higher multiples of current earnings as compared to other stocks, which may lead to inflated prices. Growth stocks often are more sensitive to market fluctuations than other securities because their market prices are highly sensitive to future earnings expectations. At times when it appears that these expectations may not be met, prices of growth stocks typically fall. Growth stocks may be more volatile than securities of slower-growing issuers.

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· 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. 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. Foreign company securities also include ADRs, which 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. 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. In certain emerging market countries, governments participate to a significant degree in their respective economies. Action by these governments could have a significant adverse effect on market prices of securities and payment of dividends. Companies with economic ties to emerging markets may be susceptible to the same risks as companies organized in emerging markets.

· Foreign Currency Risk: Investments in securities that are denominated or receiving revenues 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.

· 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 Fund - Principal Risks" section in the prospectus.

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PERFORMANCE

The bar chart and table below provide some indication of the risks of investing in the Fund by illustrating the variability of the Fund's returns. Each assumes reinvestment of dividends and distributions. The Fund's past performance, before and after taxes, is not necessarily an indication of how the Fund will perform in the future. Furthermore, high double-digit returns were achieved primarily during favorable market conditions and may not be repeated in the future.

The bar chart shows changes in the performance of the Fund's Class A shares from calendar year to calendar year. This chart does not reflect the sales charge applicable to Class A shares. If the sales charge were reflected, returns would be lower. Performance for the Fund's other share classes will vary due to the different expenses each class bears. Updated performance information is available at www.lordabbett.com or by calling 888-522-2388.

Bar Chart (per calendar year) - Class A Shares* Best Quarter 2nd Q 2020 +40.59% Worst Quarter 4th Q 2018 -23.96% *  The total return for the Fund's Class A shares for the nine-month period from January 1, 2024 to September 30, 2024 was 20.83%.

The table below shows how the Fund's average annual total returns compare to the returns of a securities market index with investment characteristics similar to those of the Fund as well as to a broad-based securities market index.¹ The Fund's average annual total returns include applicable sales charges.

The after-tax returns of Class A shares included in the table below are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. In some cases, the return after taxes on distributions and sale of Fund shares may exceed the return before taxes due to a tax benefit resulting from realized losses on a sale of Fund shares at the end of the period that is used to offset other gains. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. The after-tax returns

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shown are not relevant to investors who hold their Fund shares through tax-advantaged arrangements such as 401(k) plans or Individual Retirement Accounts ("IRAs"). After-tax returns for other share classes are not shown in the table and will vary from those shown for Class A shares.

¹The Fund has adopted the S&P 500^® Index as its broad-based securities market index.

Average Annual Total Returns
(for the periods ended December 31, 2023)
Class	1 Year	5 Years	10 Years	Life of Class	Inception Date for Performance
Class A Shares
	Before Taxes	2.28%	7.69%	6.11%	-
	After Taxes on Distributions	2.28%	5.54%	3.73%	-
	After Taxes on Distributions and Sale of Fund Shares	1.35%	6.15%	4.50%	-
Class C Shares(1)	6.68%	8.15%	5.94%	-
Class F Shares	8.61%	9.13%	6.91%	-
Class F3 Shares	8.82%	9.33%	-	10.80%	4/4/2017
Class I Shares	8.74%	9.24%	7.02%	-
Class P Shares	8.21%	8.75%	6.62%	-
Class R2 Shares	8.07%	8.58%	6.37%	-
Class R3 Shares	8.20%	8.70%	6.48%	-
Class R4 Shares	8.50%	8.98%	-	6.38%	6/30/2015
Class R5 Shares	8.74%	9.25%	-	6.64%	6/30/2015
Class R6 Shares	8.82%	9.34%	-	6.75%	6/30/2015
Index
Russell 2000® Growth Index	18.66%	9.22%	7.16%	6.72%	6/30/2015
(reflects no deduction for fees, expenses, or taxes)	7.79%	4/4/2017
S&P 500® Index	26.29%	15.69%	12.03%	12.42%	6/30/2015
(reflects no deduction for fees, expenses, or taxes)	12.99%	4/4/2017

(1)	Class C shares convert to Class A shares eight years after purchase. Class C share performance does not reflect the impact of such conversion to Class A shares.

MANAGEMENT

Investment Adviser. The Fund's investment adviser is Lord, Abbett & Co. LLC ("Lord Abbett").

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Portfolio Managers.

Portfolio Managers/Title	Member of the Portfolio Management Team Since
F. Thomas O'Halloran, Partner and Portfolio Manager	2001
Matthew R. DeCicco, Partner and Director of Equities	2002
Vernon T. Bice, Portfolio Manager	2011
Benjamin Ebel, Senior Managing Director and Portfolio Manager	2020

PURCHASE AND SALE OF FUND SHARES

The minimum initial and additional amounts shown below vary depending on the class of shares you buy and the type of account. Certain financial intermediaries may impose different restrictions than those described below. For Class I shares, the minimum investment shown below applies to certain types of institutional investors, but does not apply to registered investment advisers or retirement and benefit plans otherwise eligible to invest in Class I shares. Class P shares are closed to substantially all new investors. See "Choosing a Share Class - Investment Minimums" in the prospectus for more information.

Investment Minimums - Initial/Additional Investments
Class	A(1) and C	F, F3, P, R2, R3, R4, R5, and R6	I
General and IRAs without Invest-A-Matic Investments	Initial: $1,000 Additional: No minimum	N/A	Initial: $1 million Additional: No minimum
Invest-A-Matic Accounts(2)	Initial: $250 Additional: $50	N/A	N/A
IRAs, SIMPLE and SEP Accounts with Payroll Deductions	No minimum	N/A	N/A
Fee-Based Advisory Programs and Retirement and Benefit Plans	No minimum	No minimum	No minimum
(1) There is no investment minimum for Class A shares purchased by investors maintaining an account with a financial intermediary that has entered into an agreement with Lord Abbett Distributor LLC ("Lord Abbett Distributor") to offer Class A shares through a load-waived network or platform, which may or may not charge transaction fees. (2) There is no minimum initial investment for Invest-A-Matic accounts held directly with the Fund, including IRAs.

You may sell (redeem) shares through your securities broker, financial professional or financial intermediary on any business day the Fund calculates its net asset value ("NAV"). If you have direct account access privileges, you may redeem your shares by contacting the Fund in writing at Lord Abbett Funds Service Center, P.O. Box 534489, Pittsburgh, PA 15253-4489 (regular mail) or Attention: 534489, 500 Ross Street 154-0520, Pittsburgh, PA 15262 (overnight mail), by calling 888-522-2388 or by accessing your account online at www.lordabbett.com.

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TAX INFORMATION

The Fund's distributions, if any, generally are taxable to you as ordinary income, capital gains or a combination of the two, unless you are a tax-exempt investor or investing through a tax-advantaged arrangement, such as a 401(k) plan or an IRA. Any withdrawals from such a tax-advantaged arrangement may be taxable to you.

PAYMENTS TO BROKER-DEALERS AND OTHER FINANCIAL INTERMEDIARIES

If you purchase Fund shares through a broker-dealer or other financial intermediary (such as a bank), the Fund and the Fund's distributor or its affiliates 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 financial intermediary and your individual financial professional to recommend the Fund over another investment. Ask your individual financial professional or visit your financial intermediary's website for more information.

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Investment Company Act File Number: 811-02871
		LADG-7SUM (12/24)