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                                                                    Exhibit 4.10

                          REGISTRATION RIGHTS AGREEMENT

                             Dated as of May 7, 2001

                                 by and between

                         AFFILIATED MANAGERS GROUP, INC.

                                       And

                               MERRILL LYNCH & CO.
               Merrill Lynch, Pierce, Fenner & Smith Incorporated

                  Liquid Yield Option(TM) Notes due May 7, 2021
                             (Zero Coupon - Senior)

--------------------
(TM)  Trademark of Merrill Lynch & Co., Inc.

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                          REGISTRATION RIGHTS AGREEMENT

      THIS REGISTRATION RIGHTS AGREEMENT is made and entered into as of May 7,
2001 by and between Affiliated Managers Group, Inc., a Delaware corporation
("the Company"), and Merrill Lynch & Co., Merrill Lynch, Pierce, Fenner & Smith
Incorporated, a Delaware corporation (the "Initial Purchaser") pursuant to the
Purchase Agreement, dated as of May 1, 2001 (the "Purchase Agreement"), between
the Company and the Initial Purchaser. In order to induce the Initial Purchaser
to enter into the Purchase Agreement, the Company has agreed to provide the
registration rights set forth in this Agreement. The execution of this Agreement
is a condition to the closing under the Purchase Agreement.

      The Company agrees with the Initial Purchaser, (i) for its benefit as
Initial Purchaser and (ii) for the benefit of the beneficial owners (including
the Initial Purchaser) from time to time of the LYONs (as defined herein) and
the beneficial owners from time to time of the Underlying Common Stock (as
defined herein) issued upon conversion of the LYONs (each of the foregoing a
"Holder" and together the "Holders"), as follows:

      Section 1. Definitions

      Capitalized terms used herein without definition shall have their
respective meanings set forth in the Purchase Agreement. As used in this
Agreement, the following terms shall have the following meanings:

      "Affiliate:" With respect to any specified person, an "affiliate," as
defined in Rule 144, of such person.

      "Applicable Conversion Price:" The Applicable Conversion Price as of any
date of determination means the Applicable Principal Amount per $1,000 principal
amount at maturity of LYONs as of such date of determination divided by the
Conversion Rate in effect as of such date of determination or, if no LYONs are
then outstanding, the Conversion Rate that would be in effect were LYONs then
outstanding.

      "Applicable Principal Amount:" Applicable Principal Amount as of any date
of determination, with respect to each $1,000 principal amount at maturity of
LYONs, means the sum of the initial issue price of such LYONs ($904.95) plus
accrued original issue discount with respect to such LYON through such date of
determination.

      "Business Day:" Each Monday, Tuesday, Wednesday, Thursday and Friday that
is not a day on which banking institutions in The City of New York are
authorized or obligated by law or executive order to close.

      "Common Stock:" The shares of Common Stock, $0.01 par value, of the
Company and any other shares of common stock as may constitute "Common Stock"
for purposes of the Indenture, including the Underlying Common Stock.

      "Company:" Affiliated Managers Group, Inc., a Delaware corporation.

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      "Conversion Rate:" Conversion Rate shall have the meaning assigned such
term in the Indenture.

      "Damages Accrual Period:" See Section 2(e) hereof.

      "Damages Payment Date:" Each May 7 and November 7 in the case of LYONs and
the Underlying Common Stock.

      "Deferral Notice:" See Section 3(h) hereof.

      "Deferral Period" See Section 3(h) hereof.

      "Effectiveness Deadline Date:" See Section 2(a) hereof.

      "Effectiveness Period:" The period beginning on the Issue Date and ending
on the earlier of (a) the sale pursuant to the Initial Shelf Registration
Statement of all Registrable Securities thereunder and (b) the expiration of the
holding period applicable to such Registrable Securities held by persons not
Affiliates of the Company under Rule 144(k) under the Securities Act.

      "Event:" See Section 2(e) hereof.

      "Event Termination Date:" See Section 2(e) hereof.

      "Event Date:" See Section 2(e) hereof.

      "Exchange Act:" The Securities Exchange Act of 1934, as amended, and the
rules and regulations of the SEC promulgated thereunder.

      "Filing Deadline Date:" See Section 2(a) hereof.

      "Holder:" See the second paragraph of this Agreement.

      "Indenture:" The Indenture dated as of the date hereof between the Company
and First Union National Bank, as trustee, pursuant to which the LYONs are being
issued.

      "Initial Purchaser:" Merrill Lynch & Co., Merrill Lynch, Pierce, Fenner &
Smith Incorporated.

      "Initial Shelf Registration Statement:" See Section 2(a) hereof.

      "Issue Date:" means May 7, 2001.

      "Liquidated Damages Amount:" See Section 2(e) hereof.

      "Losses:" See Section 6 hereof.

      "LYONs:" The Liquid Yield Option Notes due May 7, 2021 of the Company to
be purchased pursuant to the Purchase Agreement.


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      "Material Event:" See Section 3(h) hereof.

      "Notice and Questionnaire:" A written notice delivered to the Company
containing the information called for by the Selling Security Holder Notice and
Questionnaire attached as Appendix A to the Offering Memorandum of the Company
dated May 1, 2001 relating to the LYONs.

      "Notice Holder:" On any date, any Holder that has delivered a Notice and
Questionnaire to the Company on or prior to such date.

      "Prospectus:" The prospectus included in any Registration Statement
(including, without limitation, a prospectus that discloses information
previously omitted from a prospectus filed as part of an effective registration
statement in reliance upon Rule 415 promulgated under the Securities Act), as
amended or supplemented by any amendment or prospectus supplement, including
post-effective amendments, and all materials incorporated by reference or
explicitly deemed to be incorporated by reference in such Prospectus.

      "Purchase Agreement:" See the first paragraph of this Agreement.

      "Record Holder:" With respect to any Damages Payment Date relating to any
LYON or Underlying Common Stock as to which any Liquidated Damages Amount has
accrued, the registered Holder of such LYON or Underlying Common Stock, as the
case may be, 15 days prior to such Damages Payment Date.

      "Registrable Securities:" The LYONs and the Underlying Common Stock, until
such securities have been converted or exchanged, and, at all times subsequent
to any such conversion or exchange, any securities into or for which such
securities have been converted or exchanged, and any security issued with
respect thereto upon any stock dividend, split or similar event until, in the
case of any such security, the earliest of (i) its effective registration under
the Securities Act and resale in accordance with the Registration Statement
covering it, (ii) expiration of the holding period that would be applicable
thereto under Rule 144(k) were it not held by an Affiliate of the Company, (iii)
its sale to the public pursuant to Rule 144 or (iv) the expiration of the
Effectiveness Period.

      "Registration Expenses:" See Section 5 hereof.

      "Registration Statement:" Any registration statement of the Company that
covers any of the Registrable Securities pursuant to the provisions of this
Agreement, including the Prospectus, amendments and supplements to such
registration statement, including post-effective amendments, all exhibits, and
all materials incorporated by reference or explicitly deemed to be incorporated
by reference in such registration statement.

      "Restricted Securities:" As this term is defined in Rule 144.

      "Rule 144:" Rule 144 under the Securities Act, as such Rule may be amended
from time to time, or any successor rule or regulation hereafter adopted by the
SEC.


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      "Rule 144A:" Rule 144A under the Securities Act, as such Rule may be
amended from time to time, or any successor rule or regulation hereafter adopted
by the SEC.

      "SEC:" The Securities and Exchange Commission.

      "Securities Act:" The Securities Act of 1933, as amended, and the rules
and regulations promulgated by the SEC thereunder.

      "Shelf Registration Statement:" See Section 2(a) hereof.

      "Subsequent Shelf Registration Statement:" See Section 2(b) hereof.

      "TIA:" The Trust Indenture Act of 1939, as amended.

      "Trustee:" First Union National Bank (or any successor entity), the
Trustee under the Indenture.

      "Underlying Common Stock:" The Common Stock into which the LYONs are
convertible or issued upon any such conversion.

      Section 2. Shelf Registration

      (a) The Company shall prepare or cause to be prepared and shall use
reasonable efforts to file or cause to be filed with the SEC, on or prior to the
date (the "Filing Deadline Date") ninety (90) days after the Issue Date, a
Registration Statement for an offering to be made on a delayed or continuous
basis pursuant to Rule 415 of the Securities Act (a "Shelf Registration
Statement") registering the resale from time to time by Holders thereof of all
of the Registrable Securities (the "Initial Shelf Registration Statement"). The
Initial Shelf Registration Statement shall be on Form S-3 or another appropriate
form permitting registration of such Registrable Securities for resale by such
Holders in accordance with the methods of distribution elected by the Holders
and set forth in the Initial Shelf Registration Statement; provided, that in no
event will such method(s) of distribution take the form of an underwritten
offering of the Registrable Securities without the prior agreement of the
Company. The Company shall use reasonable efforts to cause the Initial Shelf
Registration Statement to be declared effective under the Securities Act on or
prior to the date (the "Effectiveness Deadline Date") that is one hundred and
eighty (180) days after the Issue Date, and to keep the Initial Shelf
Registration Statement (or any Subsequent Shelf Registration Statement)
continuously effective under the Securities Act until the end of the
Effectiveness Period. At the time the Initial Shelf Registration Statement is
declared effective, each Holder that became a Notice Holder on or prior to 10
Business Days prior to such time of effectiveness shall be named as a selling
security Holder in the Initial Shelf Registration Statement and the related
Prospectus in such a manner as to permit such Holder to deliver such Prospectus
to purchasers of Registrable Securities in accordance with applicable law.

      (b) If the Initial Shelf Registration Statement or any Subsequent Shelf
Registration Statement ceases to be effective for any reason at any time during
the Effectiveness Period, the Company shall use reasonable efforts to obtain the
prompt withdrawal of any order suspending the effectiveness thereof, and in any
event shall within thirty (30) days of such cessation of


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effectiveness amend the Shelf Registration Statement in a manner reasonably
expected to obtain the withdrawal of the order suspending the effectiveness
thereof, or file an additional Shelf Registration Statement covering all of the
securities that as of the date of such filing are Registrable Securities (a
"Subsequent Shelf Registration Statement"). If a Subsequent Shelf Registration
Statement is filed, the Company shall use reasonable efforts to cause the
Subsequent Shelf Registration Statement to become effective as promptly as is
practicable after such filing and to keep such Registration Statement (or
subsequent Shelf Registration Statement) continuously effective until the end of
the Effectiveness Period.

      (c) The Company shall supplement and amend the Shelf Registration
Statement if required by the rules, regulations or instructions applicable to
the registration form used by the Company for such Shelf Registration Statement,
if required by the Securities Act or, to the extent to which the Company does
not reasonably object, as reasonably requested by the Initial Purchaser or by
the Trustee on behalf of the registered Holders.

      (d) Each Holder of Registrable Securities agrees that if such Holder
wishes to sell Registrable Securities pursuant to a Shelf Registration Statement
and related Prospectus, it will do so only in accordance with this Section 2(d)
and Section 3(h). Each Holder of Registrable Securities wishing to sell
Registrable Securities pursuant to a Shelf Registration Statement and related
Prospectus agrees to deliver a Notice and Questionnaire to the Company at least
eight (8) and not more than twenty (20) Business Days prior to any intended
distribution of Registrable Securities under the Shelf Registration Statement.
From and after the date the Initial Shelf Registration Statement is declared
effective, the Company shall, as promptly as is practicable after the date a
Notice and Questionnaire is delivered, and in any event within five (5) Business
Days after such date, (i) if required by applicable law, file with the SEC a
post-effective amendment to the Shelf Registration Statement or prepare and, if
required by applicable law, file a supplement to the related Prospectus or a
supplement or amendment to any document incorporated therein by reference or
file any other required document so that the Holder delivering such Notice and
Questionnaire is named as a selling security Holder in the Shelf Registration
Statement and the related Prospectus in such a manner as to permit such Holder
to deliver such Prospectus to purchasers of the Registrable Securities in
accordance with applicable law and, if the Company shall file a post-effective
amendment to the Shelf Registration Statement, use reasonable efforts to cause
such post-effective amendment to be declared effective under the Securities Act
as promptly as is practicable; (ii) provide such Holder copies of any documents
filed pursuant to Section 2(d)(i); and (iii) notify such Holder as promptly as
practicable after the effectiveness under the Securities Act of any
post-effective amendment filed pursuant to Section 2(d)(i); provided, that if
such Notice and Questionnaire is delivered during a Deferral Period, the Company
shall so inform the Holder delivering such Notice and Questionnaire and shall
take the actions set forth in clauses (i), (ii) and (iii) above upon expiration
of the Deferral Period in accordance with Section 3(h). Notwithstanding anything
contained herein to the contrary, the Company shall be under no obligation to
name any Holder that is not a Notice Holder as a selling security Holder in any
Registration Statement or related Prospectus; provided, however, that any Holder
that becomes a Notice Holder pursuant to the provisions of Section 2(d) of this
Agreement (whether or not such Holder was a Notice Holder at the time the
Registration Statement was declared effective) shall be named as a selling
security Holder in the Registration Statement or related Prospectus in
accordance with the requirements of this Section 2(d).


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      (e) The parties hereto agree that the Holders of Registrable Securities
will suffer damages, and that it would not be feasible to ascertain the extent
of such damages with precision, if (i) the Initial Shelf Registration Statement
has not been filed on or prior to the Filing Deadline Date, (ii) the Initial
Shelf Registration Statement has not been declared effective under the
Securities Act on or prior to the Effectiveness Deadline Date, or (iii) the
aggregate duration of Deferral Periods in any period exceeds the number of days
permitted in respect of such period pursuant to Section 3(h) hereof (each of the
events of a type described in any of the foregoing clauses (i) through (iii) are
individually referred to herein as an "Event," and the Filing Deadline Date in
the case of clause (i), the Effectiveness Deadline Date in the case of clause
(ii), the date on which the aggregate duration of Deferral Periods in any period
exceeds the number of days permitted by Section 3(h) hereof in the case of
clause (iii), being referred to herein as an "Event Date"). Events shall be
deemed to continue until the "Event Termination Date," which shall be the
following dates with respect to the respective types of Events: the date the
Initial Shelf Registration Statement is filed in the case of an Event of the
type described in clause (i), the date the Initial Shelf Registration Statement
is declared effective under the Securities Act in the case of an Event of the
type described in clause (ii) and termination of the Deferral Period that caused
the limit on the aggregate duration of Deferral Periods in a period set forth in
Section 3(h) to be exceeded in the case of the commencement of an Event of the
type described in clause (iii).

      Accordingly, commencing on (and including) any Event Date and ending on
(but excluding) the next date on which there are no Events that have occurred
and are continuing (a "Damages Accrual Period"), the Company agrees to pay, as
liquidated damages and not as a penalty, an amount (the "Liquidated Damages
Amount"), payable on (except as set forth in the following proviso) the Damages
Payment Dates to Record Holders of then outstanding LYONs that are Registrable
Securities and of then outstanding shares of Underlying Common Stock issued upon
conversion of LYONs that are Registrable Securities, as the case may be,
accruing, for each portion of such Damages Accrual Period beginning on and
including a Damages Payment Date (or, in respect of the first time that the
Liquidation Damages Amount is to be paid to Holders on a Damages Payment Date as
a result of the occurrence of any particular Event, from the Event Date) and
ending on but excluding the first to occur of (A) the date of the end of the
Damages Accrual Period or (B) the next Damages Payment Date, at a rate per annum
equal to one quarter of one percent (0.25%) for the first 90-day period from the
Event Date, and thereafter at a rate per annum equal to one-half percent (0.5%)
of the aggregate Applicable Principal Amount of such LYONs or the aggregate
Applicable Conversion Price of such shares of Underlying Common Stock if such
LYONs have been converted into Common Stock, as the case may be, in each case
determined as of the Business Day immediately preceding the next Damages Payment
Date (or, in the case of any LYON or portion thereof called for redemption or
converted as provided for in the following proviso, determined as of the
Business Day immediately preceding the applicable redemption date or conversion
date, as the case may be); provided, that any Liquidated Damages Amount accrued
with respect to any LYON or portion thereof called for redemption on a
redemption date or converted into Underlying Common Stock on a conversion date
prior to the Damages Payment Date, shall, in any such event, be paid instead to
the Record Holder who submitted such LYON or portion thereof for redemption or
conversion on the applicable redemption date or conversion date, as the case may
be, on such date (or promptly following the conversion date, in the case of
conversion).


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      Notwithstanding the foregoing, no Liquidated Damages Amounts shall accrue
as to any Registrable Security from and after the earlier of (x) the date such
security is no longer a Registrable Security and (y) expiration of the
Effectiveness Period. The rate of accrual of the Liquidated Damages Amount with
respect to any period shall not exceed the rate provided for in this paragraph
notwithstanding the occurrence of multiple concurrent Events. Following the cure
of all Events requiring the payment by the Company of Liquidated Damages Amounts
to the Holders of Registrable Securities pursuant to this Section, the accrual
of Liquidated Damages Amounts will cease (without in any way limiting the effect
of any subsequent Event requiring the payment of Liquidated Damages Amount by
the Company).

      The Trustee shall be entitled, on behalf of Holders of LYONs or Underlying
Common Stock, to seek any available remedy for the enforcement of this
Agreement, including for the payment of any Liquidated Damages Amount.
Notwithstanding the foregoing, the parties agree that the sole remedy for a
violation of the terms of this Agreement shall be such liquidated damages.

      All of the Company's obligations set forth in this Section 2(e) that are
outstanding with respect to any Registrable Security at the time such security
ceases to be a Registrable Security shall survive until such time as all such
obligations with respect to such security have been satisfied in full
(notwithstanding termination of this Agreement pursuant to Section 8(k)).

      The parties hereto agree that the liquidated damages provided for in this
Section 2(e) constitute a reasonable estimate of the damages that may be
incurred by Holders of Registrable Securities by reason of the failure of the
Shelf Registration Statement to be filed or declared effective or available for
effecting resales of Registrable Securities in accordance with the provisions
hereof.

      Section 3. Registration Procedures

      In connection with the registration obligations of the Company under
Section 2 hereof, the Company shall:

      (a) Before filing any Registration Statement or Prospectus or any
amendments or supplements thereto with the SEC, furnish to the Initial Purchaser
copies of all such documents proposed to be filed and give reasonable
consideration to such comments as the Initial Purchaser reasonably shall propose
within three (3) Business Days of the delivery of such copies to the Initial
Purchaser.

      (b) Subject to the provisions of Section 3(h), prepare and file with the
SEC such amendments and post-effective amendments to each Registration Statement
as may be necessary to keep such Registration Statement continuously effective
for the applicable period specified in Section 2(a); cause the related
Prospectus to be supplemented by any required Prospectus supplement, and as so
supplemented to be filed pursuant to Rule 424 (or any similar provisions then in
force) under the Securities Act; and use all reasonable efforts to comply with
the provisions of the Securities Act applicable to it with respect to the
disposition of all securities covered by such Registration Statement during the
Effectiveness Period in accordance with the


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intended methods of disposition by the sellers thereof set forth in such
Registration Statement as so amended or such Prospectus as so supplemented.

      (c) As promptly as practicable give notice to the Notice Holders and the
Initial Purchaser (i) when any Prospectus, Prospectus supplement, Registration
Statement or post-effective amendment to a Registration Statement (other than
any such Prospectus supplement, Registration Statement or post-effective
amendment to a Registration Statement which is filed solely to name additional
selling security holders or to reflect any other matters that are not of a
material nature) has been filed with the SEC and, with respect to a Registration
Statement or any post-effective amendment, when the same has been declared
effective, (ii) of any request, following the effectiveness of the Initial Shelf
Registration Statement under the Securities Act, by the SEC or any other federal
or state governmental authority for amendments or supplements to any
Registration Statement or related Prospectus or for additional information,
(iii) of the issuance by the SEC or any other federal or state governmental
authority of any stop order suspending the effectiveness of any Registration
Statement or the initiation or threatening of any proceedings for that purpose
and (iv) of the receipt by the Company of any notification with respect to the
suspension of the qualification or exemption from qualification of any of the
Registrable Securities for sale in any jurisdiction or the initiation or
threatening of any proceeding for such purpose, which notice may, at the
discretion of the Company (or as required pursuant to Section 3(h)), state that
it constitutes a Deferral Notice, in which event the provisions of Section 3(h)
shall apply.

      (d) Use all reasonable efforts to obtain the withdrawal of any order
suspending the effectiveness of a Registration Statement or the lifting of any
suspension of the qualification (or exemption from qualification) of any of the
Registrable Securities for sale in any jurisdiction in which they have been
qualified for sale, in either case at the earliest possible moment.

      (e) Promptly as reasonably practicable furnish to each Notice Holder and
the Initial Purchaser, upon their request and without charge, at least one (1)
conformed copy of the Registration Statement and any amendment thereto,
including financial statements but excluding schedules, all documents
incorporated or deemed to be incorporated therein by reference and all exhibits
(unless requested in writing to the Company by such Notice Holder or the Initial
Purchaser, as the case may be).

      (f) During the Effectiveness Period, deliver to each Notice Holder in
connection with any sale of Registrable Securities pursuant to a Registration
Statement, without charge, as many copies of the Prospectus or Prospectuses
relating to such Registrable Securities (including each preliminary prospectus)
and any amendment or supplement thereto as such Notice Holder may reasonably
request; and the Company hereby consents (except during such periods that a
Deferral Notice is outstanding and has not been revoked) to the use of such
Prospectus or each amendment or supplement thereto by each Notice Holder in
connection with any offering and sale of the Registrable Securities covered by
such Prospectus or any amendment or supplement thereto in the manner set forth
therein.

      (g) Prior to any public offering of the Registrable Securities pursuant to
the Shelf Registration Statement, use all reasonable efforts to register or
qualify or cooperate with the Notice Holders in connection with the registration
or qualification (or exemption from such


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registration or qualification) of such Registrable Securities for offer and sale
under the securities or Blue Sky laws of such jurisdictions within the United
States as any Notice Holder reasonably requests in writing (which request may be
included in the Notice and Questionnaire); prior to any public offering of the
Registrable Securities pursuant to the Shelf Registration Statement, use all
reasonable efforts to keep each such registration or qualification (or exemption
therefrom) effective during the Effectiveness Period in connection with such
Notice Holder's offer and sale of Registrable Securities pursuant to such
registration or qualification (or exemption therefrom) and do any and all other
acts or things necessary to enable the disposition in such jurisdictions of such
Registrable Securities in the manner set forth in the relevant Registration
Statement and the related Prospectus; provided, that the Company will not be
required to (i) qualify as a foreign corporation or as a dealer in securities in
any jurisdiction where it would not otherwise be required to qualify but for
this Agreement or (ii) take any action that would subject it to general service
of process in suits or to taxation in any such jurisdiction where it is not then
so subject.

      (h) Upon (A) the issuance by the SEC of a stop order suspending the
effectiveness of the Shelf Registration Statement or the initiation of
proceedings with respect to the Shelf Registration Statement under Section 8(d)
or 8(e) of the Securities Act, (B) the occurrence of any event or the existence
of any fact (a "Material Event") as a result of which any Registration Statement
shall contain any untrue statement of a material fact or omit to state any
material fact required to be stated therein or necessary to make the statements
therein not misleading, or any Prospectus shall contain any untrue statement of
a material fact or omit to state any material fact required to be stated therein
or necessary to make the statements therein, in the light of the circumstances
under which they were made, not misleading, or (C) the occurrence or existence
of any pending corporate development that, in the discretion of the Company,
makes it appropriate to suspend the availability of the Shelf Registration
Statement and the related Prospectus, (i) in the case of clause (B) above,
subject to the next sentence, as promptly as practicable prepare and file a
post-effective amendment to such Registration Statement or a supplement to the
related Prospectus or any document incorporated therein by reference or file any
other required document that would be incorporated by reference into such
Registration Statement and Prospectus so that such Registration Statement does
not contain any untrue statement of a material fact or omit to state any
material fact required to be stated therein or necessary to make the statements
therein not misleading, and such Prospectus does not contain any untrue
statement of a material fact or omit to state any material fact required to be
stated therein or necessary to make the statements therein, in the light of the
circumstances under which they were made, not misleading, as thereafter
delivered to the purchasers of the Registrable Securities being sold thereunder,
and, in the case of a post-effective amendment to a Registration Statement,
subject to the next sentence, use all reasonable efforts to cause it to be
declared effective as promptly as is reasonably practicable, and (ii) give
notice to the Notice Holders that the availability of the Shelf Registration
Statement is suspended (a "Deferral Notice") and, upon receipt of any Deferral
Notice, each Notice Holder agrees not to sell any Registrable Securities
pursuant to the Registration Statement until such Notice Holder's receipt of
copies of the supplemented or amended Prospectus provided for in clause (i)
above, or until it is advised in writing by the Company that the Prospectus may
be used, and has received copies of any additional or supplemental filings that
are incorporated or deemed incorporated by reference in such Prospectus. The
Company will use all reasonable efforts to ensure that the use of the Prospectus
may be resumed (x) in the case of clause (A) above, as promptly as is
practicable, (y) in the case of clause (B) above, as soon as, in the sole
judgment of the Company, public


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disclosure of such Material Event would not be prejudicial to or contrary to the
interests of the Company or, if necessary to avoid unreasonable burden or
expense, as soon as reasonably practicable thereafter and (z) in the case of
clause (C) above, as soon as, in the sole judgment of the Company, such
suspension is no longer appropriate. The period during which the availability of
the Registration Statement and any Prospectus is suspended (the "Deferral
Period") shall, without the Company incurring any obligation to pay liquidated
damages pursuant to Section 2(e), not exceed thirty (30) days in any three (3)
month period or ninety (90) days in any twelve (12) month period.

      (i) Comply with all applicable rules and regulations of the SEC and make
generally available to its securityholders earning statements (which need not be
audited) satisfying the provisions of Section 11(a) of the Securities Act and
Rule 158 thereunder (or any similar rule promulgated under the Securities Act)
no later than 45 days after the end of any 12-month period (or 90 days after the
end of any 12-month period if such period is a fiscal year) commencing on the
first day of the first fiscal quarter of the Company commencing after the
effective date of a Registration Statement, which statements shall cover said
12-month periods.

      (j) If reasonably requested in writing by a Holder or Holders of
Registrable Securities and solely at the Company's discretion, the Company will
consider an underwritten offering of Registrable Securities held by such Holder
or Holders upon terms and conditions to be agreed upon at the time of such
underwritten offering.

      (k) Cooperate with each Notice Holder to facilitate the timely preparation
and delivery of certificates representing Registrable Securities sold pursuant
to a Registration Statement, and cause such Registrable Securities to be in such
denominations as are permitted by the Indenture and registered in such names as
such Notice Holder may request in writing at least two Business Days prior to
any sale of such Registrable Securities.

      (l) Provide a CUSIP number for all Registrable Securities covered by each
Registration Statement not later than the effective date of such Registration
Statement and provide the Trustee for the LYONs and the transfer agent for the
Common Stock with printed certificates for the Registrable Securities that are
in a form eligible for deposit with The Depository Trust Company.

      (m) Make a reasonable effort to provide such information as is required
for any filings required to be made with the National Association of Securities
Dealers, Inc.

      (n) Upon (i) the filing of the Initial Shelf Registration Statement and
(ii) the effectiveness of the Initial Shelf Registration Statement, announce the
same, in each case by release to Reuters Economic Services and Bloomberg
Business News.

      (o) Cause the Indenture to be qualified under the TIA not later than the
effective date of any Registration Statement; and in connection therewith,
cooperate with the Trustee to effect such changes to the Indenture as may be
required for the Indenture to be so qualified in accordance with the terms of
the TIA and execute, and use all reasonable efforts to cause the Trustee to
execute, all documents as may be required to effect such changes, and all other
forms


                                       10
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and documents required to be filed with the SEC to enable the Indenture to be so
qualified in a timely manner.

      Section 4. Holder's Obligations

      Each Holder agrees, by acquisition of the Registrable Securities, that no
Holder of Registrable Securities shall be entitled to sell any of such
Registrable Securities pursuant to a Registration Statement or to receive a
Prospectus relating thereto, unless such Holder has furnished the Company with a
Notice and Questionnaire as required pursuant to Section 2(d) hereof (including
the information required to be included in such Notice and Questionnaire) and
the information set forth in the next sentence. Each Notice Holder agrees
promptly to furnish to the Company all information required to be disclosed in
order to make the information previously furnished to the Company by such Notice
Holder not misleading and any other information regarding such Notice Holder and
the distribution of such Registrable Securities as may be required to be
disclosed in the Registration Statement under applicable law or pursuant to SEC
comments. Each Holder further agrees, following termination of the Effectiveness
Period, to notify the Company, within 10 Business Days of request, of the amount
of Registrable Securities sold pursuant to the Registration Statement and, in
the absence of a response, the Company may assume that all of the Holder's
Registrable Securities were so sold.

      Section 5. Registration Expenses

      The Company shall bear all fees and expenses incurred in connection with
the performance by the Company of its obligations under Sections 2 and 3 of this
Agreement whether or not any of the Registration Statements are declared
effective. Such fees and expenses shall include, without limitation, (i) all
registration and filing fees (including, without limitation, fees and expenses
(x) with respect to filings, if any, required to be made by the Company with the
National Association of Securities Dealers, Inc. and (y) of compliance with
federal and state securities or Blue Sky laws (including, without limitation,
reasonable fees and disbursements of the counsel specified in the next sentence
in connection with Blue Sky qualifications of the Registrable Securities under
the laws of such jurisdictions as the Notice Holders of a majority of the
Registrable Securities being sold pursuant to a Registration Statement may
designate), (ii) printing expenses (including, without limitation, expenses of
printing certificates for Registrable Securities in a form eligible for deposit
with The Depository Trust Company), (iii) duplication expenses relating to
copies of any Registration Statement or Prospectus delivered to any Holders
hereunder, (iv) fees and disbursements of counsel for the Company in connection
with the Shelf Registration Statement, and (v) reasonable fees and disbursements
of the Trustee and its counsel and of the registrar and transfer agent for the
Common Stock. In addition, the Company shall bear or reimburse the Notice
Holders for the reasonable fees and disbursements of one firm of legal counsel
for the Holders incurred in reviewing and commenting upon the Shelf Registration
Statement prior to its effectiveness, which shall, upon the written consent of
the Initial Purchaser (which shall not be unreasonably withheld), be a
nationally recognized law firm experienced in securities law matters designated
by the Company. In addition, the Company shall pay the internal expenses of the
Company (including, without limitation, all salaries and expenses of officers
and employees performing legal or accounting duties), the expense of any annual
audit, the fees and expenses incurred in connection with the listing of the
Registrable Securities on any


                                       11
<PAGE>

securities exchange on which similar securities of the Company are then listed
and the fees and expenses of any person, including special experts, retained by
the Company.

      Section 6. Indemnification; Contribution.

      (a) The Company agrees to indemnify and hold harmless the Initial
Purchaser and each Holder of Registrable Securities and each person, if any, who
controls the Initial Purchaser or any Holder of Registrable Securities within
the meaning of either Section 15 of the Securities Act or Section 20 of the
Exchange Act, as follows:

            (i) against any and all loss, liability, claim, damage and expense
      whatsoever, as incurred, resulting from any untrue statement or alleged
      untrue statement of a material fact contained in the Registration
      Statement (or any amendment thereto), or the omission or alleged omission
      therefrom of a material fact necessary in order to make the statements
      therein, in light of the circumstances under which they were made, not
      misleading or resulting from any untrue statement or alleged untrue
      statement of a material fact included in any preliminary prospectus or the
      Prospectus (or any amendment or supplement thereto), or the omission or
      alleged omission therefrom of a material fact necessary in order to make
      the statements therein, in the light of the circumstances under which they
      were made, not misleading;

            (ii) against any and all loss, liability, claim, damage and expense
      whatsoever, as incurred, to the extent of the aggregate amount paid in
      settlement of any litigation, or any investigation or proceeding by any
      governmental agency or body, commenced or threatened, or of any claim
      whatsoever based upon any such untrue statement or omission, or any such
      alleged untrue statement or omission, provided that (subject to Section
      6(d) below) any such settlement is effected with the prior written consent
      of the Company; and

            (iii) subject to Section 6(c) below, against any and all expense
      whatsoever, as incurred (including the fees and disbursements of counsel),
      reasonably incurred in investigating, preparing or defending against any
      litigation, or any investigation or proceeding by any governmental agency
      or body, commenced or threatened, or any claim whatsoever based upon any
      such untrue statement or omission, or any such alleged untrue statement or
      omission, to the extent that any such expense is not paid under (i) or
      (ii) above;

provided, however, that this indemnity agreement shall not apply to any loss,
liability, claim, damage or expense to the extent arising out of any untrue
statement or omission or alleged untrue statement or omission made in reliance
upon and in conformity with written information furnished to the Company by or
on behalf of the Initial Purchaser or any Holder of Registrable Securities and
each person, if any, who controls the Initial Purchaser or any such Holder of
Registrable Securities expressly for use in the Registration Statement (or any
amendment thereto), or any preliminary prospectus or the Prospectus (or any
amendment or supplement thereto); provided, further, that this indemnity
agreement shall not apply to any loss, liability, claim, damage or expense (1)
arising from an offer or sale of Registrable Securities occurring during a
Deferral Period, if a Notice Holder was given a Deferral Notice, or (2) a Holder
fails to


                                       12
<PAGE>

deliver at or prior to the written confirmation of sale, the most recent
Prospectus, as amended or supplemented, and such Prospectus, as amended or
supplemented, would have corrected such untrue statement or alleged untrue
statement of a material fact or would have included the omitted or allegedly
omitted statement of a material fact.

      (b) In connection with any Shelf Registration in which a Holder,
including, without limitation, the Initial Purchaser, of Registrable Securities
is participating, in furnishing information relating to such Holder of
Registrable Securities to the Company in writing expressly for use in such
Registration Statement, any preliminary prospectus, the Prospectus or any
amendments or supplements thereto, the Holders of such Registrable Securities
agree, severally and not jointly, to indemnify and hold harmless the Initial
Purchaser and each person, if any, who controls the Initial Purchaser within the
meaning of either Section 15 of the Securities Act or Section 20 of the Exchange
Act and the Company, and each person, if any, who controls the Company within
the meaning of either such Section, against any and all loss, liability, claim,
damage and expense described in the indemnity contained in subsection (a) of
this Section, as incurred, but only with respect to untrue statements or
omissions, or alleged untrue statements or omissions, made in the Registration
Statement (or any amendment thereto), or any preliminary prospectus or the
Prospectus (or any amendment or supplement thereto) in reliance upon and in
conformity with written information furnished to the Company by or on behalf of
such Holder of Registrable Securities (which also acknowledges the indemnity
provisions herein) and each person, if any, who controls any such Holder of
Registrable Securities expressly for use in the Registration Statement (or any
amendment thereto) or such preliminary prospectus or the Prospectus (or any
amendment or supplement thereto).

      The Initial Purchaser agrees to indemnify and hold harmless the Company,
the Holders of Registrable Securities, and each person, if any, who controls the
Company or any Holder of Registrable Securities within the meaning of either
Section 15 of the Securities Act or Section 20 of the Exchange Act against any
and all loss, liability, claim, damage and expense described in the indemnity
contained in subsection (a) of this Section, as incurred, but only with respect
to untrue statements or omissions, or alleged untrue statements or omissions,
made in the Registration Statement (or any amendment thereto), or any
preliminary prospectus or the Prospectus (or any amendment or supplement
thereto) in reliance upon and in conformity with written information furnished
to the Company by or on behalf of the Initial Purchaser expressly for use in the
Registration Statement (or any amendment thereto) or such preliminary prospectus
or the Prospectus (or any amendment or supplement thereto).

      (c) Each indemnified party shall give notice as promptly as reasonably
practicable to each indemnifying party of any action commenced against it in
respect of which indemnity may be sought hereunder, but failure to so notify an
indemnifying party shall not relieve such indemnifying party from any liability
hereunder to the extent it is not materially prejudiced as a result thereof and
in any event shall not relieve it from any liability which it may have otherwise
than on account of this indemnity agreement. The indemnifying party, upon
request of the indemnified party, shall retain counsel reasonably satisfactory
to the indemnified party to represent the indemnified party and any others the
indemnifying party may designate in such proceeding and shall pay the fees and
disbursements of such counsel related to such proceeding. In any such
proceeding, any indemnified party shall have the right to retain its own
counsel, but the fees and expenses of such counsel shall be at the expense of
such indemnified party unless (i)


                                       13
<PAGE>

the indemnifying party and the indemnified party shall have mutually agreed to
the retention of such counsel or (ii) the named parties to any such proceeding
(including any impleaded parties) include both the indemnifying party and the
indemnified party and representation of both parties by the same counsel would
be inappropriate due to actual or potential differing interests between them. It
is understood that the indemnifying party shall not, in respect of the legal
expenses of any indemnified party in connection with any proceeding or related
proceedings in the same jurisdiction, be liable for (a) the fees and expenses of
more than one separate firm (in addition to any local counsel) for the Initial
Purchaser, Holders of Registrable Securities, and all persons, if any, who
control the Initial Purchaser and Holders of Registrable Securities within the
meaning of either Section 15 of the 1933 Act or Section 20 of the 1934 Act, (b)
the fees and expenses of more than one separate firm (in addition to any local
counsel) for the Company, its directors, and each person, if any, who controls
the Company within the meaning of either such Section, and that all such fees
and expenses shall be reimbursed as they are incurred. In the case of any such
separate firm for the Initial Purchaser, Holders of Registrable Securities, and
control persons of the Initial Purchaser and Holders of Registrable Securities,
such firm shall be designated in writing by the Initial Purchaser. In the case
of any such separate firm for the Company, and such directors, officers and
control persons of the Company, such firm shall be designated in writing by the
Company. The indemnifying party shall not be liable for any settlement of any
proceeding effected without its written consent, but if settled with such
consent or if there be a final judgment for the plaintiff, the indemnifying
party agrees to indemnify the indemnified party from and against any loss or
liability by reason of such settlement or judgment. Notwithstanding the
foregoing sentence, if at any time an indemnified party shall have requested an
indemnifying party to reimburse the indemnified party for fees and expenses of
counsel as contemplated by the second and third sentences of this paragraph, the
indemnifying party agrees that it shall be liable for any settlement of any
proceeding effected without its written consent if (i) such settlement is
entered into more than 45 days after receipt by such indemnifying party of the
aforesaid request, (ii) such indemnifying party shall have received notice of
the terms of such settlement at least 30 days prior to such settlement being
entered into and (iii) such indemnifying party shall not have reimbursed the
indemnified party in accordance with such request prior to the date of such
settlement. Notwithstanding the immediately preceding sentence, if at any time
an indemnified party shall have requested an indemnifying party to reimburse the
indemnified party for fees and expenses of counsel, an indemnifying party shall
not be liable for any settlement effected without its consent if such
indemnifying party (i) reimburses such indemnified party in accordance with such
request to the extent it considers such request to be reasonable and (ii)
provides written notice to the indemnified party substantiating the unpaid
balance as unreasonable, in each case prior to the date of such settlement. No
indemnifying party shall, without the prior written consent of the indemnified
parties, settle or compromise or consent to the entry of any judgment with
respect to any litigation, or any investigation or proceeding by any
governmental agency or body, commenced or threatened, or any claim whatsoever in
respect of which indemnification or contribution could be sought under this
Section 6 hereof (whether or not the indemnified parties are actual or potential
parties thereto), unless such settlement, compromise or consent (i) includes an
unconditional release of each indemnified party from all liability arising out
of such litigation, investigation, proceeding or claim and (ii) does not include
a statement as to or an admission of fault, culpability or a failure to act by
or on behalf of any indemnified party.

      (d) If at any time an indemnified party shall have requested an
indemnifying party to reimburse the indemnified party for fees and expenses of
counsel, such indemnifying party


                                       14
<PAGE>

agrees that it shall be liable for any settlement of the nature contemplated by
Section 6(a)(ii) effected without its written consent if (i) such settlement is
entered into more than 45 days after receipt by such indemnifying party of
aforesaid request, (ii) such indemnifying party shall have received notice of
the terms of such settlement at least 30 days prior to such settlement being
entered into and (iii) such indemnifying party shall not have reimbursed such
indemnified party in accordance with such request prior to the date of such
settlement. Notwithstanding the immediately preceding sentence, if at any time
an indemnified party shall have requested an indemnifying party to reimburse the
indemnified party for fees and expenses of counsel, an indemnifying party shall
not be liable for any settlement of the nature contemplated by Section 6(a)(ii)
effected without its consent if such indemnifying party (i) reimburses such
indemnified party in accordance with such request to the extent it considers
such request to be reasonable and (ii) provides written notice to the
indemnified party substantiating the unpaid balance as unreasonable, in each
case prior to the date of such settlement.

      (e) If the indemnification provided for in this Section 6 is for any
reason unavailable to or insufficient to hold harmless an indemnified party in
respect of any losses, liabilities, claims, damages or expenses referred to
therein, then each indemnifying party shall contribute to the aggregate amount
of such losses, liabilities, claims, damages and expenses incurred by such
indemnified party, as incurred, in such proportion as is appropriate to reflect
the relative fault of the indemnifying party or parties on the one hand and of
the indemnified party on the other hand in connection with the statements or
omissions which resulted in such losses, liabilities, claims, damages or
expenses, as well as any other relevant equitable considerations.

      The relative fault of the Company on the one hand and the Holders of the
Registrable Securities or the Initial Purchaser on the other hand shall be
determined by reference to, among other things, whether any such untrue or
alleged untrue statement of a material fact or omission or alleged omission to
state a material fact relates to information supplied by the Company or by the
Holders of the Registrable Securities or the Initial Purchaser and the parties'
relative intent, knowledge, access to information and opportunity to correct or
prevent such statement or omission.

      The parties hereto agree that it would not be just and equitable if
contribution pursuant to this Section 6(e) were determined by pro rata
allocation or by any other method of allocation which does not take account of
the equitable considerations referred to above in this Section 6(e). The
aggregate amount of losses, liabilities, claims, damages, and expenses incurred
by an indemnified party and referred to above in this Section 6(e) shall be
deemed to include any legal or other expenses reasonably incurred by such
indemnified party in investigating, preparing or defending against any
litigation, or any investigation or proceeding by any governmental agency or
body, commenced or threatened, or any claim whatsoever based upon any such
untrue or alleged untrue statement or omission or alleged omission.

      Notwithstanding the provisions of this Section 6, neither the Holder of
any Registrable Securities nor the Initial Purchaser, shall be required to
indemnify or contribute any amount in excess of the amount by which the total
price at which the Registrable Securities sold by such Holder of Registrable
Securities or unwritten by the Initial Purchaser, as the case may be, and
distributed to the public were offered to the public exceeds the amount of any
damages that such


                                       15
<PAGE>

Holder of Registrable Securities or the Initial Purchaser has otherwise been
required to pay by reason of such untrue or alleged untrue statement or omission
or alleged omission.

      No person guilty of fraudulent misrepresentation (within the meaning of
Section 11(f) of the Securities Act) shall be entitled to contribution from any
person who was not guilty of such fraudulent misrepresentation.

      For purposes of this Section 6(e), each person, if any, who controls the
Initial Purchaser or any Holder of Registrable Securities within the meaning of
Section 15 of the Securities Act or Section 20 of the Exchange Act shall have
the same rights to contribution as the Initial Purchaser or such Holder, and
each person, if any, who controls the Company within the meaning of Section 15
of the Securities Act or Section 20 of the Exchange Act shall have the same
rights to contribution as the Company.

      Section 7. Information Requirements

      The Company covenants that, if at any time before the end of the
Effectiveness Period the Company is not subject to the reporting requirements of
the Exchange Act, it will reasonably cooperate with any Holder of Registrable
Securities and take such further reasonable action as any Holder of Registrable
Securities may reasonably request in writing (including, without limitation,
making such reasonable representations as any such Holder may reasonably
request), all to the extent required from time to time to enable such Holder to
sell Registrable Securities without registration under the Securities Act within
the limitation of the exemptions provided by Rule 144 and Rule 144A under the
Securities Act and customarily taken in connection with sales pursuant to such
exemptions; provided, however, that any legal opinion required by any trustee or
transfer agent shall be the responsibility of such Holder. Upon the written
request of any Holder of Registrable Securities, the Company shall deliver to
such Holder a written statement as to whether it has complied with such filing
requirements, unless such a statement has been included in the Company's most
recent report required to be filed and filed pursuant to Section 13 or Section
15(d) of Exchange Act. Notwithstanding the foregoing, nothing in this Section 7
shall be deemed to require the Company to register any of its securities under
any section of the Exchange Act.

      Section 8. Miscellaneous

      (a) No Conflicting Agreements. The Company is not, as of the date hereof,
a party to, nor shall it, on or after the date of this Agreement, enter into,
any agreement with respect to its securities that conflicts with the rights
granted to the Holders of Registrable Securities in this Agreement. The Company
represents and warrants that the rights granted to the Holders of Registrable
Securities hereunder do not conflict in any material respect with the rights
granted to the Holders of the Company's securities under any other agreements.

      (b) Amendments and Waivers. The provisions of this Agreement, including
the provisions of this sentence, may not be amended, modified or supplemented,
and waivers or consents to departures from the provisions hereof may not be
given, unless the Company has obtained the written consent of Holders of a
majority of the then outstanding shares of Underlying Common Stock constituting
Registrable Securities (with Holders of LYONs deemed


                                       16
<PAGE>

to be the Holders, for purposes of this Section, of the number of outstanding
shares of Underlying Common Stock into which such LYONs are or would be
convertible or exchangeable as of the date on which such consent is requested).
Notwithstanding the foregoing, a waiver or consent to depart from the provisions
hereof with respect to a matter that relates exclusively to the rights of
Holders of Registrable Securities whose securities are being sold pursuant to a
Registration Statement and that does not directly or indirectly affect the
rights of other Holders of Registrable Securities may be given by Holders of at
least a majority of the Registrable Securities being sold by such Holders
pursuant to such Registration Statement; provided, that the provisions of this
sentence may not be amended, modified, or supplemented except in accordance with
the provisions of the immediately preceding sentence. Each Holder of Registrable
Securities outstanding at the time of any such amendment, modification,
supplement, waiver or consent or thereafter shall be bound by any such
amendment, modification, supplement, waiver or consent effected pursuant to this
Section 8(b), whether or not any notice, writing or marking indicating such
amendment, modification, supplement, waiver or consent appears on the
Registrable Securities or is delivered to such Holder.

      (c) Notices. All notices and other communications provided for or
permitted hereunder shall be made in writing by hand delivery, by telecopier, by
courier guaranteeing overnight delivery or by first-class mail, return receipt
requested, and shall be deemed given (i) when made, if made by hand delivery,
(ii) upon confirmation, if made by telecopier, (iii) one (1) Business Day after
being deposited with such courier, if made by overnight courier or (iv) on the
date indicated on the notice of receipt, if made by first-class mail, to the
parties as follows:

            (w) if to a Holder of Registrable Securities that is not a Notice
      Holder, at the address for such Holder then appearing in the Registrar (as
      defined in the Indenture);

            (x) if to a Notice Holder, at the most current address given by such
      Holder to the Company in a Notice and Questionnaire or any amendment
      thereto;

            (y) if to the Company, to:

            Affiliated Managers Group, Inc.
            Two International Place
            Boston, MA  02110
            Attention:  Treasurer
            Telecopy No.:  (617) 747-3380

            and

            (z) if to the Initial Purchaser, to:

            Merrill Lynch & Co.,
            Merrill Lynch, Pierce, Fenner & Smith Incorporated
            World Financial Center North Tower
            250 Vesey Street
            New York, New York  10080
            Attention: Syndicate Department
            Telecopy No.: (212) 449-1000


                                       17
<PAGE>

or to such other address as such person may have furnished to the other persons
identified in this Section 8(c) in writing in accordance herewith.

      (d) Approval of Holders. Whenever the consent or approval of Holders of a
specified percentage of Registrable Securities is required hereunder,
Registrable Securities held by the Company or its affiliates (as such term is
defined in Rule 405 under the Securities Act) (other than the Initial Purchaser
or subsequent Holders of Registrable Securities if such subsequent Holders are
deemed to be such affiliates solely by reason of their holdings of such
Registrable Securities) shall not be counted in determining whether such consent
or approval was given by the Holders of such required percentage.

      (e) Successors and Assigns. Any person who purchases any Registrable
Securities from the Initial Purchaser shall be deemed, for purposes of this
Agreement, to be an assignee of the Initial Purchaser. This Agreement shall
inure to the benefit of and be binding upon the successors and assigns of each
of the parties and shall inure to the benefit of and be binding upon each Holder
of any Registrable Securities other than any Holder which asserts that this
Agreement is not binding upon it.

      (f) Counterparts. This Agreement may be executed in any number of
counterparts and by the parties hereto in separate counterparts, each of which
when so executed shall be deemed to be original and all of which taken together
shall constitute one and the same agreement.

      (g) Headings. The headings in this Agreement are for convenience of
reference only and shall not limit or otherwise affect the meaning hereof.

      (h) GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.

      (i) Severability. If any term, provision, covenant or restriction of this
Agreement is held to be invalid, illegal, void or unenforceable, the remainder
of the terms, provisions, covenants and restrictions set forth herein shall
remain in full force and effect and shall in no way be affected, impaired or
invalidated thereby, and the parties hereto shall use their best efforts to find
and employ an alternative means to achieve the same or substantially the same
result as that contemplated by such term, provision, covenant or restriction, it
being intended that all of the rights and privileges of the parties shall be
enforceable to the fullest extent permitted by law.

      (j) Entire Agreement. This Agreement is intended by the parties as a final
expression of their agreement and is intended to be a complete and exclusive
statement of the agreement and understanding of the parties hereto in respect of
the subject matter contained herein and the registration rights granted by the
Company with respect to the Registrable Securities. Except as provided in the
Purchase Agreement, there are no restrictions, promises, warranties or
undertakings, other than those set forth or referred to herein, with respect to
the registration rights granted by the Company with respect to the Registrable
Securities. This Agreement supersedes all prior agreements and undertakings
among the parties with respect to such registration rights.


                                       18
<PAGE>

      (k) Termination. This Agreement and the obligations of the parties
hereunder shall terminate upon the end of the Effectiveness Period, except for
any liabilities or obligations under Sections 4, 5 or 6 hereof and the
obligations to make payments of and provide for liquidated damages under Section
2(e) hereof to the extent such damages accrue prior to the end of the
Effectiveness Period, each of which shall remain in effect in accordance with
its terms.


                                       19
<PAGE>

      IN WITNESS WHEREOF, the parties have executed this Registration Rights
Agreement as of the date first written above.

                                    AFFILIATED MANAGERS GROUP, INC.

                                    By /s/ Darrell W. Crate
                                       ------------------------------
                                       Name:  Darrell W. Crate
                                       Title: Sr. Vice President and
                                              Chief Financial Officer

Accepted as of the date first above written:

MERRILL LYNCH & CO.
MERRILL LYNCH, PIERCE, FENNER & SMITH INCORPORATED

By: /s/ Robert Aberman
    -----------------------------
    Name:  Robert Aberman
    Title: Vice President


                                       20