Document:

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                                                                     EXHIBIT 4.5

                          REGISTRATION RIGHTS AGREEMENT

          THIS REGISTRATION RIGHTS AGREEMENT (this "Agreement") is made and
entered into as of April 3, 2006, by and among AFFILIATED MANAGERS GROUP, INC.,
a Delaware corporation (the "Company"), AMG CAPITAL TRUST I, a statutory trust
organized under the laws of the State of Delaware (the "Trust" and together with
the Company, the "Issuers"), and BANC OF AMERICA SECURITIES LLC, GOLDMAN, SACHS
& CO. and MERRILL LYNCH, PIERCE, FENNER & SMITH INCORPORATED (each an initial
purchaser and, collectively the "Initial Purchasers").

          This Agreement is made pursuant to the Purchase Agreement, dated March
28, 2006 (the "Purchase Agreement"), among the Issuers and the Initial
Purchasers with respect to the issue and sale by the Trust and the purchase by
the Initial Purchasers of 5,820,000 5.10% Convertible Trust Preferred Securities
(liquidation amount $50 per security) representing undivided beneficial
interests in the assets of the Trust (the "Preferred Securities"). The entire
proceeds from the sale of the Preferred Securities will be combined with the
entire proceeds from the sale by the Trust to the Company of its common
securities (liquidation amount $50 per security) (the "Common Securities") and
will be used by the Trust to purchase $300,000,000 aggregate principal amount of
the Company's 5.10% Junior Subordinated Convertible Debentures due April 15,
2036 (the "Debentures"). The Preferred Securities are guaranteed by the Company
as to the payment of distributions and payments upon liquidation or redemption,
and benefiting from certain additional undertakings of the Company to the extent
set forth in the Guarantee Agreement between the Company and LaSalle Bank
National Association, as trustee thereunder, dated the date hereof (the
"Guarantee"), and are convertible into the common stock, par value $0.01 per
share (the "Common Stock"), of the Company. In order to induce the Initial
Purchasers to enter into the Purchase Agreement, the Issuers have 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 Issuers agree with the Initial Purchasers, (i) for the benefit of
the Initial Purchasers and (ii) for the benefit of the beneficial owners
(including the Initial Purchasers) from time to time of the Preferred Securities
and the Debentures, and the beneficial owners from time to time of the
Underlying Common Stock (as defined herein) issued upon conversion of the
Preferred Securities or the Debentures, if any, (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.

          "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 required by law, regulation or executive order to remain closed.

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          "Common Stock:" The 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:" See the first paragraph hereof.

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

          "Damages Payment Date:" Each January 15, April 15, July 15 and October
15.

          "Debentures" or "Debenture:" See the second paragraph hereof.

          "Declaration:" The Amended and Restated Declaration of Trust, dated as
of the date hereof, between the Company among the Company, as depositor, the
trustees named therein and the holders from time to time of undivided beneficial
interests in the assets of the Trust, pursuant to which the Preferred Securities
and Common Securities are being issued.

          "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 (i) the sale pursuant to the Initial Shelf Registration
Statement of all Registrable Securities thereunder and (ii) two years following
the latest issuance of the Preferred Securities or the Debentures.

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

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

          "Event Termination 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.

          "Guarantee:" See the second paragraph hereof.

          "Holder:" See the third paragraph hereof.

          "Indenture:" The Indenture, dated as of the date hereof, between the
Company and LaSalle Bank National Association, as debenture trustee, pursuant to
which the Debentures are being issued.

          "Initial Purchasers:" See the first paragraph of this Agreement.

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

          "Issue Date:" means April 3, 2006.

          "Issuer Free Writing Prospectus:" See Section 2(d) hereof.

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

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

          "Notice and Questionnaire:" A written notice delivered to the Company
containing substantially the information called for by the Selling
Securityholder Notice and Questionnaire attached as Annex A to the Offering
Memorandum of the Issuers, dated March 28, 2006, relating to the Preferred
Securities.

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

          "Preferred Securities" or "Preferred Security:" See the second
paragraph hereof.

          "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 in such
Prospectus.

          "Purchase Agreement:" See the second paragraph hereof.

          "Record Date:" With respect to any Damages Payment Date relating to
any Preferred Security or Debenture as to which any Liquidated Damages Amount
has accrued, (i) the 15th day immediately preceding such Damages Payment Date if
the Damages Accrual Period has not ended, or (ii) the date of the end of the
Damages Accrual Period.

          "Record Holder:" With respect to any Damages Payment Date relating to
any Preferred Security or Debenture as to which any Liquidated Damages Amount
has accrued, the registered holder of such Preferred Security or Debenture, as
applicable, on the Record Date.

          "Registrable Securities:" The Securities, 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, merger 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)
its sale to the public pursuant to Rule 144 or (iii) the expiration of the
Effectiveness Period.

          "Registration Statement:" Any registration statement of the Company
that covers any of the Registrable Securities pursuant to the provisions of this
Agreement, including the

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Prospectus, amendments and supplements to such registration statement, including
post-effective amendments, all exhibits, and all materials incorporated by
reference in such registration statement.

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

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

          "SEC:" The Securities and Exchange Commission.

          "Securities:" Collectively means the Preferred Securities, the
Debentures and the Underlying Common Stock.

          "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:" LaSalle Bank National Association (or any successor
entity), in its role as Debenture Trustee under the Indenture and in its role as
Property Trustee under the Declaration.

          "Underlying Common Stock:" The Common Stock into which the Preferred
Securities and Debentures 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 no later than a
date which is ninety (90) days after the Issue Date (the "Filing Deadline 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 by 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

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Securities Act until the expiration of the Effectiveness Period, subject to the
rights of the Company under Section 3(h) to create a Deferral Period. At the
time the Initial Shelf Registration Statement is declared effective, each Holder
that became a Notice Holder on or prior to the date ten (10) Business Days prior
to such time of effectiveness shall be named as a selling securityholder 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
effectiveness amend the Shelf Registration Statement in a manner reasonably
expected by the Company 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 Purchasers 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) but 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 reasonably 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 document required by the SEC so that the Holder delivering
such Notice and Questionnaire is named as a selling securityholder 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

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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 securityholder 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 initially declared effective) shall be named as a
selling securityholder in the Registration Statement or related Prospectus
subject to and in accordance with the requirements of this Section 2(d).

          The Issuers represent and agree that, unless they obtain the prior
consent of a majority of the Registrable Securities that are registered under
the Shelf Registration Statement at such time or the approval of the counsel for
the holders of Registrable Securities or the consent of the Initial Purchasers
in connection with any underwritten offering of Registrable Securities, and each
Holder represents and agrees that, unless it obtains the prior consent of the
Issuers and the Initial Purchasers, it will not make any offer relating to the
Securities that would constitute an "issuer free writing prospectus," as defined
in Rule 433 (an "Issuer Free Writing Prospectus"), or that would otherwise
constitute a "free writing prospectus," as defined in Rule 405, required to be
filed with the SEC. The Issuers represent that any Issuer Free Writing
Prospectus, when taken together with the information in the Shelf Registration
Statement and the Prospectus, will not include any untrue statement of a
material fact or omit to state any material fact necessary in order to make the
statements therein, in light of the circumstances under which they were made,
not misleading.

          (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), and 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).

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          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 the Damages Payment Dates to Record Holders of then
outstanding Debentures that are Registrable Securities (and the Trust agrees to
pay such amounts to the holders of the Preferred Securities) 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 Record Holders on a Damages Payment Date as a result of
the occurrence of any particular Event, beginning on and including 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
of one percent (0.50%) of the aggregate principal amount of such Debentures,
determined as of the Record Date.

          Notwithstanding the foregoing, no Liquidated Damages Amounts shall
accrue as to any Underlying Common Stock at any time nor as to any Debenture
(and the corresponding Preferred 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
2(e) 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 the Preferred
Securities, the Debentures or the Underlying Common Stock, to seek any available
remedy for the enforcement of this Agreement, including, with respect to
Preferred Securities and Debentures, 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 Issuers' 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(j)).

          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 Record Holders of then outstanding Preferred Securities and
Debentures that are 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. In no event will additional interest be payable in connection with a
registration default relating to the failure to register the Common Stock
deliverable upon conversion of the Preferred Securities or the Debentures.

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     SECTION 3. REGISTRATION PROCEDURES. In connection with the registration
obligations of the Issuers under Section 2 hereof, the Issuers shall:

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

          (b) Subject to 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 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 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 Purchasers (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 or the Trust 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) As promptly as reasonably practicable furnish to each Notice
Holder and the Initial Purchasers, upon their request and without charge, at
least one (1) conformed copy of

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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 or the Trust by such Notice Holder or the Initial Purchasers, 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) Subject to Section 3(h), 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
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
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 neither the Company nor the
Trust will be required to (i) qualify as a foreign corporation or as a dealer in
securities in any jurisdiction where they are not otherwise qualified but for
this Agreement or (ii) take any action that would subject them to general
service of process in suits or to taxation in any such jurisdiction where they
are 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 Company's discretion, 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

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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 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 or the Trust 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 Issuers
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 practicable, (y) in
the case of clause (B) above, as soon as, in the sole judgment of the Company,
public disclosure of such Material Event would not be prejudicial to or contrary
to the interests of the Company or the Trust, 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 or the Trust 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 the Company's 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 forty-five (45) days after the end of any
12-month period (or ninety (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 Declaration and 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.

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          (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 Preferred Securities and
the Debentures and the transfer agent for the Common Stock with certificates for
the Registrable Securities that are in a form eligible for deposit with The
Depository Trust Company.

          (m) Make 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.; and

          (o) Cause the Declaration, the Indenture and the Guarantee 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 Declaration, the Indenture and the Guarantee as may be
required for the each such document to be so qualified in accordance with the
terms of the TIA and execute, and use reasonable efforts to cause the Trustee to
execute, all documents as may be required to effect such changes, and all other
forms and documents required to be filed with the SEC to enable the Declaration,
the Indenture and the Guarantee 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 Effective Period, to notify the Company within ten
(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 Issuers of their
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, 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

                                       11

<Page>

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 Issuers 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 Purchasers (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 Issuers (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 securities exchange on which
the same securities of the Company are then listed and the fees and expenses of
any person, including special experts, retained by the Company or the Trust.

     SECTION 6. INDEMNIFICATION; CONTRIBUTION.

          (a) The Issuers agree, jointly and severally, to indemnify and hold
harmless each of the Initial Purchasers and each Holder of Registrable
Securities and each person, if any, who controls any 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 any Issuer Free Writing 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

                                       12

<Page>

          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 or the
Trust by any Initial Purchaser on their own behalf or any Holder of Registrable
Securities and each person, if any, who controls any 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) or any Issuer Free Writing
Prospectus (or any amendment or supplement thereto); provided, further, that
this indemnity agreement shall not apply to any loss, liability, claim, damage
or expense arising from an offer or sale of Registrable Securities occurring
during a Deferral Period, if a Notice Holder was given a Deferral Notice.

          (b) In connection with any Shelf Registration in which a Holder,
including, without limitation, any Initial Purchaser, of Registrable Securities
is participating, in furnishing information relating to such Holder of
Registrable Securities to the Company or the Trust in writing expressly for use
in such Registration Statement, any preliminary prospectus, the Prospectus or
any Issuer Free Writing 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 Purchasers and each person, if any, who
controls any Initial Purchaser within the meaning of either Section 15 of the
Securities Act or Section 20 of the Exchange Act and the Company and the Trust,
and each person, if any, who controls either the Company or the Trust 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) or any Issuer Free Writing
Prospectus (or any amendment or supplement thereto) in reliance upon and in
conformity with written information furnished to the Company or the Trust by or
on behalf of such Holder of Registrable Securities (which also acknowledges the
indemnity provisions herein) or any 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) or any Issuer Free Writing Prospectus (or any
amendment or supplement thereto).

          Each Initial Purchaser severally agrees to indemnify and hold harmless
the Issuers, the Holders of Registrable Securities, and each person, if any, who
controls the Company or the Trust 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) or

                                       13

<Page>

any Issuer Free Writing Prospectus (or any amendment or supplement thereto) in
reliance upon and in conformity with written information furnished to the
Issuers by such 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) or any Issuer Free Writing
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) 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 Purchasers, Holders of
Registrable Securities, and all persons, if any, who control any Initial
Purchaser or Holders of Registrable Securities within the meaning of either
Section 15 of the Securities Act or Section 20 of the Exchange Act, collectively
(b) the fees and expenses of more than one separate firm (in addition to any
local counsel) for the Issuers, their directors, and each person, if any, who
controls the Company or the Trust 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 Purchasers, Holders of
Registrable Securities, and control persons of any Initial Purchaser and Holders
of Registrable Securities, such firm shall be designated in writing by the
Initial Purchasers. In the case of any such separate firm for the Issuers, and
such directors, officers and control persons of the Company or the Trust, such
firm shall be designated in writing by the Issuers. 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 forty-five (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 thirty (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

                                       14

<Page>

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 (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 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 forty-five (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 thirty (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 (1) reimburses such
indemnified party in accordance with such request to the extent it considers
such request to be reasonable and (2) 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 Issuers on the one hand and the Holders of
the Registrable Securities or the Initial Purchasers 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 Issuers or by the
Holders of the Registrable Securities or the Initial Purchasers

                                       15

<Page>

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 (even if the Initial Purchasers were treated as one entity for such
purpose) 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 any 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 by any such 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 Holder of Registrable Securities or any such 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
an 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 such Initial Purchaser or such Holder, and
each person, if any, who controls the Company or the Trust 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 and the Trust.

     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, the Company will 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 exemption provided by Rule
144A under the Securities Act and customarily taken in connection with sales
pursuant to such exemption; 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

                                       16

<Page>

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; NO CONFLICTING AGREEMENTS. Neither the Company
nor the Trust is, as of the date hereof, a party to, nor shall the Company or
the Trust, on or after the date of this Agreement, enter into any agreement with
respect to their securities that conflicts with the rights granted to the
Holders of Registrable Securities in this Agreement. The Issuers represent and
warrant 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 securities of the Company or the Trust under any other
agreements.

          (a) 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 Issuers have obtained the written consent of
Holders of a majority of the then outstanding Underlying Common Stock
constituting Registrable Securities (with Holders of Preferred Securities and
Debentures deemed to be the Holders, for purposes of this Section, of the number
of outstanding shares of Underlying Common Stock into which such Preferred
Securities and Debentures 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(a), 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.

          (b) 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 Security Register
(as defined in the Indenture);

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

          (y) if to the Company, to:

                                       17

<Page>

               Affiliated Managers Group, Inc.
               600 Hale Street
               Prides Crossing, MA 01965
               Attention: Treasurer
               Telecopy No.: (617) 747-3380

               with a copy to:

               Ropes & Gray LLP
               One International Place
               Boston, MA 02110
               Attention: Keith F. Higgins
               Telecopy No.: (617) 951-7050

               and

          (z) if to the Initial Purchasers, to:

               Banc of America Securities LLC
               9 West 57th Street
               New York, New York 10019
               Attention: Raymond P. Ko, Assistant General Counsel
               Telecopy No.: (212) 457-3745; and

               Goldman, Sachs & Co.
               85 Broad Street
               New York, New York 10004
               Attention: Registration Department
               Telecopy No.: (212) 902-3000; and

               Merrill Lynch & Co.,
               Merrill Lynch, Pierce, Fenner & Smith
                  Incorporated
               4 World Financial Center
               New York, New York 10080
               Attention: Paul A. Pepe
               Telecopy No.: (212) 449-6714

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.

          (c) 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 the Trust or their respective
affiliates (as such term is defined in Rule 405 under the Securities Act) (other
than the Initial Purchasers or subsequent Holders of Registrable Securities if
such subsequent Holders are deemed to be such affiliates solely by reason of
their

                                       18

<Page>

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.

          (d) SUCCESSORS AND ASSIGNS. Any person who purchases any Registrable
Securities from any Initial Purchaser shall be deemed, for purposes of this
Agreement, to be an assignee of such 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.

          (e) 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.

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

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

          (h) 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.

          (i) 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 Issuers 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 Issuers with respect to
the Registrable Securities. This Agreement supersedes all prior agreements and
undertakings among the parties solely with respect to such registration rights.

          (j) 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.

                            [SIGNATURE PAGE FOLLOWS]

                                       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/ John Kingston, III
                                            ------------------------------------
                                        Name: John Kingston, III
                                        Title: Senior Vice President, General
                                               Counsel and Secretary

                                        AMG Capital Trust I

                                        By: LaSalle Bank National Association,
                                            not in its individual capacity but
                                            solely as Administrative Trustee

                                        By: /s/ Michael Oliver
                                            ------------------------------------
                                        Name: Michael Oliver
                                        Title: Assistant Vice President

Accepted as of the date first above
written:

BANC OF AMERICA SECURITIES LLC

By: /s/ Thomas Morrison
    ---------------------------------
Name: Thomas Morrison
Title: Managing Director

By: GOLDMAN, SACHS & CO.

By: /s/ Goldman, Sachs & Co.
    ---------------------------------
    (Goldman, Sachs & Co.)

MERRILL LYNCH, PIERCE, FENNER & SMITH
INCORPORATED

By: /s/ John R. Erickson
    ---------------------------------
Name: John R. Erickson
Title: Director<Page>
                                                                   Exhibit 4.7

                                            CROSS-REFERENCE TABLE

<Table>
<Caption>
 TRUST INDENTURE ACT                                                       DECLARATION OF TRUST
      SECTION                                                                    SECTION
--------------------------------------------------------------------------------------------------
<S>                     <C>                                               <C>
     Section 310        (a)(1)  ......................................... 5.3
                        (a)(2)  ......................................... 5.3
                        (a)(3)  ......................................... 5.1
                        (a)(4)  ......................................... Not Applicable
                        (a)(5)  ......................................... 5.3(a)
                           (b)  ......................................... 5.3(c)
                           (c)  ......................................... Not Applicable
     Section 311           (a)  ......................................... 2.2(b)
                           (b)  ......................................... 2.2(b)
                           (c)  ......................................... Not Applicable
     Section 312           (a)  ......................................... 2.2(a)
                           (b)  ......................................... 2.2(b)
                           (c)  ......................................... Not Applicable
     Section 313           (a)  ......................................... 2.3
                           (b)  ......................................... 2.3
                           (c)  ......................................... 2.3, 15.1
                           (d)  ......................................... 2.3
     Section 314           (a)  ......................................... 2.4, 3.6(k)
                           (b)  ......................................... Not Applicable
                        (c)(1)  ......................................... 2.5
                        (c)(2)  ......................................... 2.5
                        (c)(3)  ......................................... 2.5
                           (d)  ......................................... Not Applicable
                           (e)  ......................................... 2.5
                           (f)  ......................................... Not Applicable
     Section 315           (a)  ......................................... 3.9, 3.10(a)
                           (b)  ......................................... 2.7, 15.1
                           (c)  ......................................... 3.9(a)
                           (d)  ......................................... 3.9(b)
                           (e)  ......................................... Not Applicable
     Section 316           (a)  ......................................... 7.8
                     (a)(1)(A)  ......................................... 2.6(c)
                     (a)(1)(B)  ......................................... 2.6(b), 2.6(c), 2.6(d)
                        (a)(2)  ......................................... Not Applicable
                           (b)  ......................................... 12.1(c)
                           (c)  ......................................... 3.6(e)
     Section 317        (a)(1)  ......................................... 3.8(h)
                        (a)(2)  ......................................... 3.8(h)
                           (b)  ......................................... 3.8(i), 7.5
     Section           318 (a)  ......................................... 2.1(b)
</Table>

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