Investment Grade Floating Rate Fund

SALES CHARGE REDUCTIONS AND WAIVERS

Please inform the fund company or your financial intermediary at the time of your purchase of fund shares if you believe you qualify for a reduced front-end sales charge.

Reducing Your Class A Share Front-End Sales Charge
You may purchase Class A shares at a discount if you qualify under the circumstances outlined below. To receive a reduced front-end sales charge, you must let the fund or your financial intermediary know at the time of your purchase of fund shares that you believe you qualify for a discount. If you or a related party have holdings of eligible funds (as defined below) in other accounts with your financial intermediary or with other financial intermediaries that may be combined with your current purchases in determining the sales charge as described below, you must inform a fund or your financial intermediary. You may be asked to provide supporting account statements or other information to allow us or your financial intermediary to verify your eligibility for a discount. If you or your financial intermediary do not notify a fund or provide the requested information, you may not receive the reduced sales charge for which you otherwise qualify. Class A shares may be purchased at a discount if you qualify under either of the following conditions:

• Rights of Accumulation - A Purchaser (as defined below) may combine thevalue of Class A, A1, C, F, and P shares of any Eligible Fund currentlyowned with a new purchase of Class A shares of any Eligible Fund in orderto reduce the sales charge on the new purchase. Class F3, I, R2, R3, R4, R5,and R6 share holdings may not be combined for these purposes.To the extent that your financial intermediary is able to do so, the value ofClass A, A1, C, F, and P shares of Eligible Funds determined for the purposeof reducing the sales charge of a new purchase under the Rights ofAccumulation will be calculated at the higher of: (1) the aggregate currentmaximum offering price of your existing Class A, A1, C, F, and P shares ofEligible Funds; or (2) the aggregate amount you invested in such shares(including dividend reinvestments but excluding capital appreciation) less anyredemptions. You should retain any information and account recordsnecessary to substantiate the historical amounts you and any relatedPurchasers have invested in Eligible Funds. You must inform the Fund and/or your financial intermediary at the time of purchase if you believe yourpurchase qualifies for a reduced sales charge and you may be requested toprovide documentation of your holdings in order to verify your eligibility. Ifyou do not do so, you may not receive all sales charge reductions for whichyou are eligible.

• Letter of Intention — In order to reduce your Class A front-end salescharge, a Purchaser may combine purchases of Class A, A1, C, F, and Pshares of any Eligible Fund the Purchaser intends to make over the next13 months in determining the applicable sales charge. The 13-month Letterof Intention period commences on the day that the Letter of Intention isreceived by the Fund, and the Purchaser must tell the Fund that laterpurchases are subject to the Letter of Intention. Purchases submitted prior tothe date the Letter of Intention is received by the Fund are not countedtoward the sales charge reduction. Current holdings under Rights ofAccumulation may be included in a Letter of Intention in order to reduce thesales charge for purchases during the 13-month period covered by the Letterof Intention. Shares purchased through reinvestment of dividends ordistributions are not included. Class F3, I, R2, R3, R4, R5, and R6 shareholdings may not be combined for these purposes. Class A and A1 shares valued at up to 5% of the amount of intended purchases are escrowed andmay be redeemed to cover the additional sales charges payable if the intendedpurchases under the Letter of Intention are not completed. The Letter ofIntention is neither a binding obligation on you to buy, nor on the Fund tosell, any or all of the intended purchase amount.

Purchaser — A Purchaser includes: (1) an individual; (2) an individual, his or her spouse, domestic partner, and childrenunder the age of 21; (3) retirement and benefit plansincluding a 401(k) plan, profit-sharing plan, moneypurchase plan, defined benefit plan, and 457(b) plan sponsored by a governmental entity, non-profitorganization, school district or church to which employer contributions are made, as well as SIMPLE IRAplans and SEP-IRA plans; or (4) a trustee or other fiduciary purchasing shares for a single trust, estate orsingle fiduciary account or a trust established by the individual as grantor. An individual may include underitem (1) his or her holdings in Eligible Funds as described below in IRAs, as a sole participant of aretirement and benefit plan sponsored by the individual’s business, and as a participant in a 403(b) plan towhich only pre-tax salary deferrals are made. An individual, his or her spouse, and domestic partner mayinclude under item (2) their holdings in IRAs, and as the sole participants in retirement and benefit planssponsored by a business owned by either or both of them. A retirement and benefit plan under item (3)includes all qualified retirement and benefit plans of a single employer and its consolidated subsidiaries,and all qualified retirement and benefit plans of multiple employers registered in the name of a singlebank trustee.

Eligible fund — An eligible fund is any Lord Abbett-sponsored fund except for (1) each portfolio of Lord Abbett Series Fund, Inc., (2) Lord Abbett U.S. Government & Government Sponsored Enterprises Money Market Fund, Inc. ("Money Market Fund") (except for holdings in Money Market Fund, which are attributable to any shares exchanged from the Lord Abbett-sponsored funds), and (3) any other fund the shares of which are not available to the investor at the time of the transaction due to a limitation on the offering of a fund's shares.

Front-end Sales Charge Waivers
Class A shares may be purchased without a front-end sales charge under any of the following conditions:

• purchases of $1 million or more (may be subject to a CDSC);
• purchases by retirement and benefit plans with at least 100 eligible employees (may be subject to a CDSC);
• purchases for retirement and benefit plans made through financial intermediaries that perform participant recordkeeping or other administrative services for the plans and that have entered into special arrangements with a fund and/or Lord Abbett Distributor specifically for such purchases (may be subject to a CDSC);
• purchases made by or on behalf of financial intermediaries for clients that pay the financial intermediaries fees in connection with fee-based advisory program, provided that the financial intermediaries or their trading agents have entered into special arrangements with a fund and/or Lord Abbett Distributor specifically for such purchases; and
• certain other types of investors may qualify to purchase Class A share without a front-end sales charge as described in the Statement of Additional Information (SAI).