Exhibit 4.4

REMARKETING AGREEMENT

REMARKETING AGREEMENT, dated as of February 12, 2004 (this “Remarketing Agreement”) by and among Affiliated Managers Group, Inc., a company organized and existing under the laws of the State of Delaware (the “Company”), The Bank of New York, a New York banking corporation, not individually but solely as Purchase Contract Agent and as attorney-in-fact of the holders of Purchase Contracts (each as defined in the Purchase Contract Agreement (as defined herein)), and Merrill Lynch & Co., Merrill Lynch, Pierce, Fenner & Smith Incorporated (“Merrill Lynch”).

WITNESSETH:

WHEREAS, the Company will issue its PRIDES (the “PRIDES”) in an aggregate Stated Amount of $250,000,000 under the Purchase Contract Agreement, dated as of February 12, 2004, by and between the Purchase Contract Agent and the Company (the “Purchase Contract Agreement”) as amended or supplemented from time to time; and

WHEREAS, the Company will issue concurrently in connection with the issuance of the PRIDES 4.125% Senior Notes of the Company initially due February 17, 2010 (the “Senior Notes”) in an aggregate principal amount of $250,000,000; and

WHEREAS, the PRIDES will initially consist of 250,000 units referred to as “Income PRIDES,” each such security consisting of a Senior Note in the principal amount of $1,000 and a Purchase Contract issued by the Company (“Purchase Contract”) pursuant to the Purchase Contract Agreement, and no Growth PRIDES, each such security consisting of certain U.S. Treasury Securities and a Purchase Contract; and

WHEREAS, the Senior Notes forming a part of the Income PRIDES will be pledged pursuant to the Pledge Agreement (the “Pledge Agreement”), dated as of February 12, 2004, by and among the Company, The Bank of New York, as Collateral Agent, Purchase Contract Agent, Securities Intermediary and Custodial Agent (the “Collateral Agent”), to secure an Income PRIDES Holder’s obligations under the related Purchase Contract on the Purchase Contract Settlement Date; and

WHEREAS, the Remarketing Agent will remarket in the manner provided herein the Senior Notes pledged pursuant to the Pledge Agreement (the “Pledged Senior Notes”) of the Income PRIDES Holders who have not already settled their Purchase Contracts, and any Senior Notes that are not pledged pursuant to the Pledge Agreement (the “Other Senior Notes”) of the holders who have elected to have their Senior Notes remarketed, in each case, as provided in the Purchase Contract Agreement; and

WHEREAS, in the event of a Failed Initial Remarketing, the holders of the Other Senior Notes electing to have their Senior Notes remarketed and of the Holders of the Pledged Senior Notes who have elected not to settle the Purchase Contracts related to their Income PRIDES by Cash Settlement and who have not settled their Purchase Contracts early upon the occurrence of certain specified corporate transactions will be remarketed by the Remarketing Agent on the

third Business Day immediately preceding the Purchase Contract Settlement Date (the “Final Remarketing Date”); and

WHEREAS, in the event of a Successful Initial Remarketing, the applicable interest rate on the Senior Notes will be reset on the Reset Date, to the Reset Rate to be determined by the Reset Agent as the rate that such Senior Notes should bear in order for the Applicable Principal Amount of the Senior Notes to have an approximate aggregate market value of 100.25% of the Treasury Portfolio Purchase Price on the Initial Remarketing Date plus the applicable Remarketing Fee, provided that in the determination of such Reset Rate, the Company shall, if applicable, limit the Reset Rate to the maximum rate permitted by applicable law; and

WHEREAS, in the event of a Failed Final Remarketing, the applicable interest rate on the Senior Notes that remain outstanding on and after the Purchase Contract Settlement Date will be reset on the third Business Day immediately preceding the Purchase Contract Settlement Date, to the Reset Rate to be determined by the Reset Agent as the rate that such Senior Notes should bear in order to have an approximate market value of 100.25% of the aggregate principal amount of the Senior Notes on the third Business Day immediately preceding the Purchase Contract Settlement Date plus the applicable Remarketing Fee, provided that in the determination of such Reset Rate, the Company shall, if applicable, limit the Reset Rate to the maximum rate permitted by applicable law; and

WHEREAS, the Company has requested Merrill Lynch to act as the Reset Agent and as the Remarketing Agent, and as such to perform the services described herein; and

WHEREAS, Merrill Lynch is willing to act as Reset Agent and Remarketing Agent and as such to perform such duties on the terms and conditions expressly set forth herein.

NOW, THEREFORE, for and in consideration of the covenants herein made, and subject to the conditions herein set forth, the parties hereto agree as follows:

Section 1.                Definitions .  Capitalized terms used and not defined in this Remarketing Agreement shall have the meanings assigned to them in the Purchase Contract Agreement or, if not therein defined, the Pledge Agreement.

Section 2.                Appointment and Obligations of Reset Agent and Remarketing Agent; Remarketing.

(a)            The Company hereby appoints Merrill Lynch and Merrill Lynch hereby accepts such appointment, (i) as the Reset Agent to determine in consultation with the Company, in the manner provided for herein and in the Indenture (as in effect on the date of this Remarketing Agreement) with respect to the Senior Notes, (1) the Reset Rate that, in the opinion of the Reset Agent, will, when applied to the Senior Notes, enable the Applicable Principal Amount of the Senior Notes to have an approximate aggregate market value of 100.25% of the Treasury Portfolio Purchase Price as of an Initial Remarketing Date, and (2) in the event of a Failed Initial Remarketing, the Reset Rate that, in the opinion of the Reset Agent, will, when applied to the Senior Notes, enable a Senior Note to have an approximate market value of 100.25% of the aggregate principal amount of the Senior Notes as of the third Business Day preceding the Purchase Contract Settlement Date, provided, in each case, that the Company, by notice to the

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Reset Agent prior to the tenth Business Day preceding a proposed Initial Remarketing Date, or the Purchase Contract Settlement Date, in the case of the Final Remarketing (as defined below), shall, if applicable, limit the Reset Rate so that it does not exceed the maximum rate permitted by applicable law and (ii) as the exclusive Remarketing Agent (subject to the right of Merrill Lynch to appoint additional remarketing agents hereunder as described below) to (1) remarket the Other Senior Notes of the holders electing to have such Other Senior Notes remarketed and the Pledged Senior Notes of the Income PRIDES Holders on an Initial Remarketing Date, for settlement on the third Business Day following such remarketing and (2) in the case of a Failed Initial Remarketing, remarket the Senior Notes of the holders of the Other Senior Notes and of the Income PRIDES Holders who have not settled the related Purchase Contracts early and have failed to notify the Purchase Contract Agent, on or prior to the fifth Business Day immediately preceding the Purchase Contract Settlement Date, of their intention to settle the related Purchase Contracts through Cash Settlement.  In connection with any remarketing contemplated hereby, the Remarketing Agent will enter into a Supplemental Remarketing Agreement (the “Supplemental Remarketing Agreement”) with the Company and the Purchase Contract Agent, which shall either be (i) substantially in the form attached hereto as Exhibit A (with such changes as the Company and the Remarketing Agent may agree upon, it being understood that changes may be necessary in the representations, warranties, covenants and other provisions of the Supplemental Remarketing Agreement due to changes in law or facts and circumstances or in the event that Merrill Lynch is not the sole remarketing agent, and with such further changes therein as the Remarketing Agent may reasonably request) or (ii) in such other form as the Remarketing Agent may reasonably request, subject to the approval of the Company (such approval not to be unreasonably withheld).  Notwithstanding anything herein to the contrary, Merrill Lynch shall not be obligated to act as Remarketing Agent or Reset Agent hereunder unless the Supplemental Remarketing Agreement is in form and substance reasonably satisfactory to Merrill Lynch.  The Company agrees that Merrill Lynch shall have the right, on 15 Business Days’ notice to the Company, to appoint one or more additional remarketing agents so long as any such additional remarketing agents shall be reasonably acceptable to the Company. Upon any such appointment, the parties shall enter into an appropriate amendment to this Remarketing Agreement to reflect the addition of any such remarketing agent.

(b)            Pursuant to the Supplemental Remarketing Agreement, the Remarketing Agent, either as sole remarketing agent or as representative of a group of remarketing agents appointed as aforesaid, will agree, subject to the terms and conditions set forth herein and therein, to use its reasonable efforts to (i) remarket, on each Initial Remarketing Date (each an “Initial Remarketing”), the Senior Notes that the Collateral Agent shall have notified the Remarketing Agent have been tendered for, or otherwise are to be included in, such Initial Remarketing, at a price per Senior Note such that the aggregate price for the Applicable Principal Amount of the Senior Notes is approximately 100.25% of the Treasury Portfolio Purchase Price plus the Remarketing Fee and (ii) in the event of a Failed Initial Remarketing, remarket, on the third Business Day immediately preceding the Purchase Contract Settlement Date (the “Final Remarketing”), the Senior Notes that the Collateral Agent shall have notified the Remarketing Agent have been tendered for, or otherwise are to be included in, the Final Remarketing, at a price of approximately 100.25% of the aggregate principal amount of such Senior Notes plus the Remarketing Fee. Notwithstanding the preceding sentence, the Remarketing Agent shall not remarket any Senior Notes for a price less than the price necessary for the Applicable Principal Amount of the Senior Notes to have an aggregate price equal to 100% of the Treasury Portfolio

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Purchase Price (the “Minimum Initial Remarketing Price”), in the case of any Initial Remarketing, or the aggregate principal amount of such Senior Notes, in the case of the Final Remarketing.  After deducting the fee specified in Section 3 below, the proceeds of such Initial Remarketing or Final Remarketing, as the case may be, shall be paid to the Collateral Agent in accordance with Section 4.6 or 6.3 of the Pledge Agreement and Section 5.3 of the Purchase Contract Agreement (each of which Sections are incorporated herein by reference).  The right of each holder of Senior Notes or Income PRIDES to have Senior Notes tendered for any Initial Remarketing or the Final Remarketing, as the case may be, shall be limited to the extent that (i) the Remarketing Agent conducts an Initial Remarketing and, in the event of a Failed Initial Remarketing, a Final Remarketing pursuant to the terms of this Remarketing Agreement, (ii) Senior Notes tendered have not been called for redemption, (iii) the Remarketing Agent is able to find a purchaser or purchasers for tendered Senior Notes at a price of not less than the Minimum Initial Remarketing Price, in the case of any Initial Remarketing, and 100% of the principal amount thereof, in the case of the Final Remarketing and (iv) such purchaser or purchasers deliver the purchase price therefor to the Remarketing Agent as and when required.  The Remarketing Agent shall not be obligated to remarket any Senior Note if a condition precedent to such remarketing is not fulfilled.

(c)            Neither the Remarketing Agent nor the Reset Agent shall have any obligation whatsoever to purchase any Senior Notes, whether in an Initial Remarketing, the Final Remarketing or otherwise, and shall in no way be obligated to provide funds to make payment upon tender of Senior Notes for remarketing or to otherwise expend or risk their own funds or incur or be exposed to financial liability in the performance of their respective duties under this Remarketing Agreement or any Supplemental Remarketing Agreement, and, without limitation of the foregoing, the Remarketing Agent shall not be deemed an underwriter of the remarketed Senior Notes.  The Company shall not be obligated in any case to provide funds to make payment upon tender of Senior Notes for remarketing.

Section 3.                Fees .  In the event of a Successful Initial Remarketing, the Remarketing Agent shall retain as a remarketing fee (the “Remarketing Fee”) (i) an amount not exceeding 25 basis points (0.25%) of the Minimum Initial Remarketing Price from any amount received in connection with such Initial Remarketing in excess of the Minimum Initial Remarketing Price if the remarketed Senior Notes mature on or prior to February 17, 2010 or (ii) such other amount as agreed between the Company and the Remarketing Agent if the maturity date of the Senior Notes is otherwise extended on the Reset Date to a date after February 17, 2010.  In the event of a Successful Final Remarketing, the Remarketing Agent shall retain as the Remarketing Fee an amount not exceeding 25 basis points (0.25%), of the principal amount of the remarketed Senior Notes from any amount received in connection with such Final Remarketing in excess of the aggregate principal amount of such remarketed Senior Notes if the remarketed Senior Notes mature on or prior to February 17, 2010 or (ii) such other amount as agreed between the Company and the Remarketing Agent if the maturity date of the Senior Notes is otherwise extended on the Reset Date to a date after February 17, 2010.  In addition, the Reset Agent shall, in either case, receive from the Company a reasonable and customary fee (the “Reset Agent Fee”); provided, however, that if the Remarketing Agent shall also act as the Reset Agent, then the Reset Agent shall not be entitled to receive any such Reset Agent Fee.  Payment of such Reset Agent Fee shall be made by the Company on the Initial Remarketing Date, in the case of a Successful Initial Remarketing, or on the third Business Day immediately preceding the

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Purchase Contract Settlement Date, in the case of a Successful Final Remarketing, in immediately available funds or, upon the instructions of the Reset Agent, by certified or official bank check or checks or by wire transfer.

Section 4.                Replacement and Resignation of Remarketing Agent.

(a)            The Company may in its absolute discretion replace Merrill Lynch as the Remarketing Agent and/or as the Reset Agent in its capacity hereunder by giving notice (i) prior to 3:00 p.m., New York City time on the eleventh Business Day immediately prior to any Initial Remarketing Date, or (ii) in the event of a Failed Initial Remarketing, prior to 3:00 p.m., New York City time on the eleventh Business Day immediately prior to the Purchase Contract Settlement Date, provided, in either case, that the Company must replace Merrill Lynch both as Remarketing Agent and as Reset Agent unless Merrill Lynch shall agree to continue to serve solely in one such capacity.  Any such replacement shall become effective upon the Company’s appointment of a successor to perform the services that would otherwise be performed hereunder by the Remarketing Agent and/or the Reset Agent.  Upon providing such notice, the Company shall use all reasonable efforts to appoint such a successor and to enter into a remarketing agreement with such successor as soon as reasonably practicable.  The Company shall notify the Purchase Contract Agent, the Collateral Agent and the Custodial Agent of the appointment of any such successor.

(b)            Merrill Lynch may resign at any time and be discharged from its duties and obligations hereunder as the Remarketing Agent and/or as the Reset Agent by giving notice (i) prior to 3:00 p.m., New York City time on the eleventh Business Day immediately prior to any Initial Remarketing Date, or (ii) in the event of a Failed Initial Remarketing, prior to 3:00 p.m., New York City time on the eleventh Business Day immediately prior to the Purchase Contract Settlement Date.  Any such resignation shall become effective upon the Company’s appointment of a successor to perform the services that would otherwise be performed hereunder by the Remarketing Agent and/or the Reset Agent. Upon receiving notice from the Remarketing Agent and/or the Reset Agent that it wishes to resign hereunder, the Company shall use all reasonable efforts to appoint such a successor and enter into a remarketing agreement with it as soon as reasonably practicable.  The Company shall notify the Purchase Contract Agent, the Collateral Agent and the Custodial Agent of the appointment of any such successor.

Section 5.                Dealing in the Securities .  Each of the Remarketing Agent and the Reset Agent, when acting hereunder or under the Supplemental Remarketing Agreement or acting in its individual or any other capacity, may, to the extent permitted by law, buy, sell, hold or deal in any of the Senior Notes, Securities or other securities of the Company.  With respect to any Senior Notes, Securities or other securities of the Company owned by it, the Remarketing Agent and the Reset Agent may each exercise any vote or join in any action with like effect as if it did not act in any capacity hereunder.  The Remarketing Agent and the Reset Agent respectively, in its individual capacity, either as principal or agent, may also engage in or have an interest in any financial or other transaction with the Company as freely as if it did not act in any capacity hereunder.

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Section 6.                Registration Statement and Prospectus .

(a)            In connection with any Initial Remarketing, the Company in its sole discretion, may determine to (i) file and cause to be declared effective a registration statement relating to the Senior Notes under the Securities Act of 1933, as amended (the “1933 Act”), prior to the third Business Day immediately preceding such Initial Remarketing Date, (ii) furnish a current preliminary prospectus and, if applicable, a current preliminary prospectus supplement to be used by the Remarketing Agent in such Initial Remarketing not later than seven Business Days prior to such Initial Remarketing Date (or such earlier date as the Remarketing Agent may reasonably request) and in such quantities as the Remarketing Agent may reasonably request, and (iii) furnish a current final prospectus and, if applicable, a final prospectus supplement to be used by the Remarketing Agent in such Initial Remarketing not later than the third Business Day immediately preceding such Initial Remarketing Date in such quantities as the Remarketing Agent may reasonably request.

(b)            In the event of a Failed Initial Remarketing and in connection with the Final Remarketing, the Company in its sole discretion, may determine to (i) file and cause to be declared effective a registration statement relating to the Senior Notes under the 1933 Act prior to the third Business Day immediately preceding the Purchase Contract Settlement Date, (ii) furnish a current preliminary prospectus and, if applicable, a current preliminary prospectus supplement to be used by the Remarketing Agent in the Final Remarketing not later than seven Business Days prior to the Purchase Contract Settlement Date (or such earlier date as the Remarketing Agent may reasonably request) and in such quantities as the Remarketing Agent may reasonably request, and (iii) furnish a current final prospectus and, if applicable, a final prospectus supplement to be us