<PAGE>

                                                                    Exhibit 4.9

                     --------------------------------------

                         AFFILIATED MANAGERS GROUP, INC.

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

                     --------------------------------------

                                    INDENTURE

                             Dated as of May 7, 2001

                     --------------------------------------

                           FIRST UNION NATIONAL BANK,

                                     TRUSTEE

                     --------------------------------------

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

<PAGE>

                             CROSS REFERENCE TABLE1

                                                                       Indenture
TIA Section                                                             Section
-----------                                                             -------

310(a)(1)................................................................ 7.10
(a)(2)................................................................... 7.10
(a)(3)................................................................... N.A.
(a)(4)................................................................... N.A.
(b).................................................................7.08; 7.10
(c)...................................................................... N.A.
311(a) ...................................................................7.11
(b)...................................................................... 7.11
(c)...................................................................... N.A.
312(a) ...................................................................2.05
(b)......................................................................12.03
(c)......................................................................12.03
313(a) ...................................................................7.06
(b)(1)....................................................................N.A.
(b)(2)....................................................................7.06
(c)......................................................................12.02
(d).......................................................................7.06
314(a) ......................................................4.02; 4.03; 12.02
(b).......................................................................N.A.
(c)(1)...................................................................12.04
(c)(2)...................................................................12.04
(c)(3)....................................................................N.A.
(d).......................................................................N.A.
(e)......................................................................12.05
(f).......................................................................N.A.
315(a) ...................................................................7.01
(b)................................................................7.05; 12.02
(c).......................................................................7.01
(d).......................................................................7.01
(e).......................................................................6.11
316(a) (last sentence) ...................................................2.08
(a)(1)(A) ................................................................6.05
(a)(1)(B).................................................................6.04
(a)(2)....................................................................N.A.
(b).......................................................................6.07
317(a)(1).................................................................6.08
(a)(2)....................................................................6.09
(b).......................................................................2.04
318(a)...................................................................12.01

                           N.A. means Not Applicable.

--------
(1)   Note: This Cross Reference Table shall not, for any purpose, be deemed to
      be part of the Indenture.
<PAGE>

                                TABLE OF CONTENTS

                                                                            Page
                                                                            ----

                                   ARTICLE I.
                   DEFINITIONS AND INCORPORATION BY REFERENCE

      SECTION 1.01.    Definitions...........................................1
      SECTION 1.02.    Other Definitions.....................................5
      SECTION 1.03.    Incorporation by Reference of Trust Indenture Act.....6
      SECTION 1.04.    Rules of Construction.................................6
      SECTION 1.05.    Acts of Holders.......................................7

                                   ARTICLE II.
                                 THE SECURITIES

      SECTION 2.01.    Form and Dating.......................................7
      SECTION 2.02.    Execution and Authentication..........................9
      SECTION 2.03.    Registrar, Paying Agent and Conversion Agent..........9
      SECTION 2.04.    Paying Agent to Hold Money and Securities in Trust...10
      SECTION 2.05.    Securityholder Lists.................................10
      SECTION 2.06.    Transfer and Exchange................................11
      SECTION 2.07.    Replacement Securities...............................12
      SECTION 2.08.    Outstanding Securities; Determinations of
                       Holders' Action .....................................13
      SECTION 2.09.    Temporary Securities.................................13
      SECTION 2.10.    Cancellation.........................................14
      SECTION 2.11.    Persons Deemed Owners................................14
      SECTION 2.12.    Global Securities....................................14
      SECTION 2.13.    CUSIP Numbers........................................19

                                  ARTICLE III.
                            REDEMPTION AND PURCHASES

      SECTION 3.01.    Right to Redeem; Notices to Trustee..................19
      SECTION 3.02.    Selection of Securities to Be Redeemed...............19
      SECTION 3.03.    Notice of Redemption.................................20
      SECTION 3.04.    Effect of Notice of Redemption.......................21
      SECTION 3.05.    Deposit of Redemption Price..........................21
      SECTION 3.06.    Securities Redeemed in Part..........................21
      SECTION 3.07.    Conversion Arrangement on Call for Redemption........21
      SECTION 3.08.    Purchase of Securities at Option of the Holder.......22
      SECTION 3.09.    Purchase of Securities at Option of the Holder upon
                       Change in Control....................................27
      SECTION 3.10.    Effect of Purchase Notice or Change in Control
                       Purchase Notice......................................30
      SECTION 3.11.    Deposit of Purchase Price or Change in Control
                       Purchase Price.......................................31
      SECTION 3.12.    Securities Purchased in Part.........................32


                                        i
<PAGE>

      SECTION 3.13.    Covenant to Comply With Securities Laws Upon
                       Purchase of Securities...............................32
      SECTION 3.14.    Repayment to the Company.............................32

                                   ARTICLE IV.
                                    COVENANTS

      SECTION 4.01.    Payment of Securities................................32
      SECTION 4.02.    SEC and Other Reports................................33
      SECTION 4.03.    Compliance Certificate...............................33
      SECTION 4.04.    Further Instruments and Acts.........................33
      SECTION 4.05.    Maintenance of Office or Agency......................34
      SECTION 4.06.    Delivery of Certain Information......................34
      SECTION 4.07.    Calculation of Original Issue Discount...............34

                                   ARTICLE V.
                              SUCCESSOR CORPORATION

      SECTION 5.01.    When Company May Merge or Transfer Assets............34

                                   ARTICLE VI.
                              DEFAULTS AND REMEDIES

      SECTION 6.01.    Events of Default....................................35
      SECTION 6.02.    Acceleration.........................................37
      SECTION 6.03.    Other Remedies.......................................38
      SECTION 6.04.    Waiver of Past Defaults..............................38
      SECTION 6.05.    Control by Majority..................................38
      SECTION 6.06.    Limitation on Suits..................................38
      SECTION 6.07.    Rights of Holders to Receive Payment.................39
      SECTION 6.08.    Collection Suit by Trustee...........................39
      SECTION 6.09.    Trustee May File Proofs of Claim.....................39
      SECTION 6.10.    Priorities...........................................40
      SECTION 6.11.    Undertaking for Costs................................40
      SECTION 6.12.    Waiver of Stay, Extension or Usury Laws..............40

                                  ARTICLE VII.
                                     TRUSTEE

      SECTION 7.01.    Duties of Trustee....................................41
      SECTION 7.02.    Rights of Trustee....................................42
      SECTION 7.03.    Individual Rights of Trustee.........................43
      SECTION 7.04.    Trustee's Disclaimer.................................43
      SECTION 7.05.    Notice of Defaults...................................43
      SECTION 7.06.    Reports by Trustee to Holders........................44
      SECTION 7.07.    Compensation and Indemnity...........................44
      SECTION 7.08.    Replacement of Trustee...............................45
      SECTION 7.09.    Successor Trustee by Merger..........................45


                                       ii
<PAGE>

      SECTION 7.10.    Eligibility; Disqualification........................45
      SECTION 7.11.    Preferential Collection of Claims Against Company....46

                                  ARTICLE VIII.
                             DISCHARGE OF INDENTURE

      SECTION 8.01.    Discharge of Liability on Securities.................46
      SECTION 8.02.    Repayment to the Company.............................46

                                   ARTICLE IX.
                                   AMENDMENTS

      SECTION 9.01.    Without Consent of Holders...........................46
      SECTION 9.02.    With Consent of Holders..............................47
      SECTION 9.03.    Compliance with Trust Indenture Act..................47
      SECTION 9.04.    Revocation and Effect of Consents, Waivers
                       and Actions..........................................47
      SECTION 9.05.    Notation on or Exchange of Securities................48
      SECTION 9.06.    Trustee to Sign Supplemental Indentures..............48
      SECTION 9.07.    Effect of Supplemental Indentures....................48

                                   ARTICLE X.
                          SPECIAL TAX EVENT CONVERSION

      SECTION 10.01.   Optional Conversion to Semiannual Coupon Note
                       Upon Tax Event ......................................48
      SECTION 10.02.   Payment of Interest; Interest Rights Preserved.......49

                                   ARTICLE XI.
                                   CONVERSION

      SECTION 11.01.   Conversion Privilege.................................50
      SECTION 11.02.   Conversion Procedure.................................51
      SECTION 11.03.   Fractional Shares....................................52
      SECTION 11.04.   Taxes on Conversion..................................52
      SECTION 11.05.   Company to Provide Stock.............................53
      SECTION 11.06.   Adjustment for Change in Capital Stock...............53
      SECTION 11.07.   Adjustment for Rights Issue..........................54
      SECTION 11.08.   Adjustment for Other Distributions...................55
      SECTION 11.09.   When Adjustment May Be Deferred......................56
      SECTION 11.10.   When No Adjustment Required..........................56
      SECTION 11.11.   Notice of Adjustment.................................57
      SECTION 11.12.   Voluntary Increase...................................57
      SECTION 11.13.   Notice of Certain Transactions.......................57
      SECTION 11.14.   Reorganization of Company; Special Distributions.....58
      SECTION 11.15.   Company Determination Final..........................58
      SECTION 11.16.   Trustee's Adjustment Disclaimer......................58
      SECTION 11.17.   Simultaneous Adjustments.............................59
      SECTION 11.18.   Successive Adjustments...............................59


                                       iii
<PAGE>

      SECTION 11.19.   Rights Issued in Respect of Common Stock Issued
                       Upon Conversion......................................59

                                  ARTICLE XII.
                                  MISCELLANEOUS

      SECTION 12.01.   Trust Indenture Act Controls.........................59
      SECTION 12.02.   Notices..............................................59
      SECTION 12.03.   Communication by Holders with Other Holders..........60
      SECTION 12.04.   Certificate and Opinion as to Conditions Precedent...60
      SECTION 12.05.   Statements Required in Certificate or Opinion........60
      SECTION 12.06.   Separability Clause..................................61
      SECTION 12.07.   Rules by Trustee, Paying Agent, Conversion Agent
                       and Registrar........................................61
      SECTION 12.08.   Legal Holidays.......................................61
      SECTION 12.09.   GOVERNING LAW........................................61
      SECTION 12.10.   No Recourse Against Others...........................61
      SECTION 12.11.   Successors...........................................61
      SECTION 12.12.   Multiple Originals...................................61

EXHIBIT A-1   FORM OF SECURITY
EXHIBIT A-2   FORM OF CERTIFICATED SECURITY
EXHIBIT B-1   FORM OF TRANSFER CERTIFICATE
EXHIBIT B-2   FORM OF LETTER TO BE DELIVERED BY ACCREDITED INVESTORS


                                       iv
<PAGE>

      INDENTURE dated as of May 7, 2001 between AFFILIATED MANAGERS GROUP, INC.,
a Delaware corporation ("Company"), and First Union National Bank, a national
banking association ("Trustee").

      Each party agrees as follows for the benefit of the other party and for
the equal and ratable benefit of the Holders of the Company's Liquid Yield
Option(TM)(TM) Trademark of Merrill Lynch & Co., Inc. Notes due May 7, 2021
(Zero Coupon - Senior) (the "Securities"):

                                   ARTICLE I.

                   DEFINITIONS AND INCORPORATION BY REFERENCE

SECTION 1.01. Definitions.

      "144A Global Security" means a permanent Global Security in the form of
the Security attached hereto as Exhibit A-1, and that is deposited with and
registered in the name of the Depositary, representing Securities sold in
reliance on Rule 144A under the Securities Act.

      "Affiliate" of any specified person means any other person directly or
indirectly controlling or controlled by or under direct or indirect common
control with such specified person. For the purposes of this definition,
"control" when used with respect to any specified person means the power to
direct or cause the direction of the management and policies of such person,
directly or indirectly, whether through the ownership of voting securities, by
contract or otherwise; and the terms "controlling" and "controlled" have
meanings correlative to the foregoing.

      "Applicable Procedures" means, with respect to any transfer or transaction
involving a Global Security or beneficial interest therein, the rules and
procedures of the Depositary for such Security, in each case to the extent
applicable to such transaction and as in effect from time to time.

      "Board of Directors" means either the board of directors of the Company or
any duly authorized committee of such board.

      "Business Day" means each day of the year other than a Saturday or a
Sunday on which banking institutions are not required or authorized to close in
the City of New York.

      "Capital Stock" for any corporation means any and all shares, interests,
rights to purchase, warrants, options, participations or other equivalents of or
interests in (however designated) stock issued by that corporation.

      "Certificated Securities" means Securities that are in the form of the
Securities attached hereto as Exhibit A-2.

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

      "Common Stock" shall mean the shares of Common Stock, $0.01 par value, of
the Company as it exists on the date of this Indenture or any other shares of
Capital Stock of the Company into which the Common Stock shall be reclassified
or changed.

      "Company" means the party named as the "Company" in the first paragraph of
this Indenture until a successor replaces it pursuant to the applicable
provisions of this Indenture and, thereafter, shall mean such successor. The
foregoing sentence shall likewise apply to any such subsequent successor or
successors.

      "Company Request" or "Company Order" means a written request or order
signed in the name of the Company by any two Officers and delivered to the
Trustee.

      "Corporate Trust Office" means the principal office of the Trustee at
which at any time its corporate trust business shall be administered, which
office at the dated hereof is located at One World Trade Center, Suite 4711, New
York, NY 10048, Attention: Corporate Trust - Bond Administration, or such other
address as the Trustee may designate from time to time by notice to the Holders
and the Company, or the principal corporate trust office of any successor
Trustee (or such other address as a successor Trustee may designate from time to
time by notice to the Holders and the Company).

      "Debt" means with respect to the Company at any date, without duplication,
obligations (other than nonrecourse obligations) under any bond, debenture, note
or other evidence of indebtedness for money borrowed by the Company.

      "Default" means any event which is, or after notice or passage of time or
both would be, an Event of Default.

      "Global Securities" means Securities that are in the form of the
Securities attached hereto as Exhibit A-1, and to the extent that such
Securities are required to bear the Legend required by Section 2.06, such
Securities will be in the form of a 144A Global Security.

      "Holder" or "Securityholder" means a person in whose name a Security is
registered on the Registrar's books.

      "Indenture" means this Indenture, as amended or supplemented from time to
time in accordance with the terms hereof, including the provisions of the TIA
that are deemed to be a part hereof.

      "Institutional Accredited Investor Security" means a Security in the form
of the Security attached hereto as Exhibit A-2, representing Securities sold to
institutional "accredited investors" (as defined in Rule 501(a)(1), (2), (3) and
(7) under the Securities Act).

      "Issue Date" of any Security means the date on which the Security was
originally issued or deemed issued as set forth on the face of the Security.

      "Issue Price" of any Security means, in connection with the original
issuance of such Security, the initial issue price at which the Security is sold
as set forth on the face of the Security.


                                       2
<PAGE>

      "Officer" means the Chairman of the Board, the President, any Senior Vice
President, any Vice President, the Treasurer, the Secretary, any Assistant
Treasurer or any Assistant Secretary of the Company.

      "Officers' Certificate" means a written certificate containing the
information specified in Sections 12.04 and 12.05, signed in the name of the
Company by any two Officers and delivered to the Trustee. An Officers'
Certificate given pursuant to Section 4.03 shall be signed by the principal
executive, financial or accounting officer of the Company but need not contain
the information specified in Sections 12.04 and 12.05.

      "Opinion of Counsel" means a written opinion containing the information
specified in Sections 12.04 and 12.05, from legal counsel who is acceptable to
the Trustee. The counsel may be an employee of, or counsel to, the Company or
the Trustee.

      "Original Issue Discount" of any Security means the difference between the
Issue Price and the Principal Amount at Maturity of the Security as set forth on
the face of the Security.

      "person" or "Person" means any individual, corporation, limited liability
company, partnership, joint venture, association, joint-stock company, trust,
unincorporated organization, or government or any agency or political
subdivision thereof.

      "Principal Amount at Maturity" of a Security means the Principal Amount at
Maturity as set forth on the face of the Security.

      "Redemption Date" or "redemption date" shall mean the date specified for
redemption of the Securities in accordance with the terms of the Securities and
this Indenture.

      "Redemption Price" or "redemption price" shall have the meaning set forth
in paragraph 5 of the Securities.

      "Responsible Officer", when used with respect to the Trustee, means any
officer within the corporate trust department (or any successor group) including
without limitation any vice president, any assistant vice president, any trust
officer or any other officer of the Trustee customarily performing functions
similar to those performed by any of the above- designated officers and also
means, with respect to a particular corporate trust matter, any other officer to
whom such matter is referred because of his knowledge of and familiarity with
the particular subject.

      "Restricted Security" means a Security required to bear the restrictive
legend set forth in the form of Security set forth in Exhibits A-1 and A-2 of
this Indenture.

      "Rule 144A" means Rule 144A under the Securities Act (or any successor
provision), as it may be amended from time to time.

      "SEC" means the Securities and Exchange Commission.

      "Securities" means any of the Company's Liquid Yield Option Notes due 2021
(Zero Coupon-Senior), as amended or supplemented from time to time, issued under
this Indenture.


                                       3
<PAGE>

      "Securityholder" or "Holder" means a person in whose name a Security is
registered on the Registrar's books.

      "Special Record Date" means, for the payment of any Defaulted Interest,
the date fixed by the Trustee pursuant to Section 10.02(b).

      "Stated Maturity", when used with respect to any Security, means the date
specified in such Security as the fixed date on which an amount equal to the
Principal Amount at Maturity of such Security is due and payable.

      "Subsidiary" means (i) a corporation, a majority of whose Capital Stock
with voting power, under ordinary circumstances, to elect directors is, at the
date of determination, directly or indirectly owned by the Company, by one or
more Subsidiaries of the Company or by the Company and one or more Subsidiaries
of the Company, (ii) a partnership in which the Company or a Subsidiary of the
Company, one or more Subsidiaries of the Company or the Company and one or more
Subsidiaries of the Company holds a majority interest in the equity capital or
profits of such partnership, or (iii) any other person (other than a
corporation) in which the Company, one or more Subsidiaries of the Company or
the Company and one or more Subsidiaries of the Company, directly or indirectly,
at the date of determination, has (x) at least a majority ownership interest or
(y) the power to elect or direct the election of a majority of the directors or
other governing body of such person.

      "Tax Event" means that the Company shall have received an opinion from
independent tax counsel experienced in such matters to the effect that, on or
after May 1, 2001, as a result of (a) any amendment to, or change (including any
announced prospective change) in, the laws (or any regulations thereunder) of
the United States or any political subdivision or taxing authority thereof or
therein or (b) any amendment to, or change in, an interpretation or application
of such laws or regulations by any legislative body, court, governmental agency
or regulatory authority, in each case which amendment or change is enacted,
promulgated, issued or announced or which interpretation is issued or announced
or which action is taken, on or after May 1, 2001, there is more than an
insubstantial risk that interest (including Original Issue Discount) payable on
the Securities either (i) would not be deductible on a current accrual basis or
(ii) would not be deductible under any other method, in either case in whole or
in part, by the Company (by reason of deferral, disallowance, or otherwise) for
United States Federal income tax purposes.

      "TIA" means the Trust Indenture Act of 1939 as in effect on the date of
this Indenture, provided, however, that in the event the TIA is amended after
such date, TIA means, to the extent required by any such amendment, the TIA as
so amended.

      "trading day" means a day during which trading in securities generally
occurs on the New York Stock Exchange or, if the Common Stock is not listed on
the New York Stock Exchange, on the principal other national or regional
securities exchange on which the Common Stock is then listed or, if the Common
Stock is not listed on a national or regional securities exchange, on the
National Association of Securities Dealers Automated Quotation System or, if the
Common Stock is not quoted on the National Association of Securities Dealers
Automated Quotation System, on the principal other market on which the Common
Stock is then traded.


                                       4
<PAGE>

      "Trustee" means the party named as the "Trustee" in the first paragraph of
this Indenture until a successor replaces it pursuant to the applicable
provisions of this Indenture and, thereafter, shall mean such successor. The
foregoing sentence shall likewise apply to any subsequent such successor or
successors.

SECTION 1.02. Other Definitions.

                                                                        Defined
   Term                                                               in Section
----------                                                            ----------

"Act"..................................................................1.05(a)
"Agent Members"........................................................2.12(e)
"Associate"............................................................3.09(a)
"Average Sale Price".....................................................11.01
"Bankruptcy Law"..........................................................6.01
"beneficial owner".....................................................3.09(a)
"cash".................................................................3.08(b)
"Change in Control"....................................................3.09(a)
"Change in Control Purchase Date"......................................3.09(a)
"Change in Control Purchase Notice"....................................3.09(c)
"Change in Control Purchase Price".....................................3.09(a)
"Company Notice".......................................................3.08(e)
"Company Notice Date"..................................................3.08(c)
"Conversion Agent"........................................................2.03
"Conversion Date"........................................................11.02
"Conversion Rate"........................................................11.01
"Custodian"...............................................................6.01
"Defaulted Interest"..................................................10.02(b)
"Depositary"...........................................................2.01(a)
"DTC"..................................................................2.01(a)
"Event of Default"........................................................6.01
"Exchange Act".........................................................3.08(d)
"Ex-Dividend Time".......................................................11.01
"Extraordinary Cash Dividend"............................................11.08
"Institutional Accredited Investors"...................................2.01(b)
"Interest Payment Date"..................................................10.01
"Legal Holiday"..........................................................12.08
"Legend"...............................................................2.06(f)
"Market Price".........................................................3.08(d)
"Measurement Period".....................................................11.08
"Notice of Default".......................................................6.01
"Option Exercise Date"...................................................10.01
"Over-Allotment Option"...................................................2.02
"Paying Agent"............................................................2.03
"Purchase Date"........................................................3.08(a)
"Purchase Notice"......................................................3.08(a)
"Purchase Price".......................................................3.08(a)


                                       5
<PAGE>

                                                                        Defined
   Term                                                               in Section
----------                                                            ----------

"QIB"..................................................................2.01(a)
"Registrar"...............................................................2.03
"Regular Record Date"....................................................10.01
"Relevant Cash Dividends"................................................11.08
"Restated Principal Amount"..............................................10.01
"Rights".................................................................11.19
"Rights Agreement".......................................................11.19
"Rule 144A Information"...................................................4.06
"Sale Price"...........................................................3.08(d)
"Securities Act".......................................................3.08(d)
"Tax Event Date".........................................................10.01
"Time of Determination"..................................................11.01

      SECTION 1.03. Incorporation by Reference of Trust Indenture Act. Whenever
this Indenture refers to a provision of the TIA, the provision is incorporated
by reference in and made a part of this Indenture. The following TIA terms used
in this Indenture have the following meanings:

      "Commission" means the SEC.

      "indenture securities" means the Securities.

      "indenture security holder" means a Securityholder.

      "indenture to be qualified" means this Indenture.

      "indenture trustee" or "institutional trustee" means the Trustee.

      "obligor" on the indenture securities means the Company.

      All other TIA terms used in this Indenture that are defined by the TIA,
defined by TIA reference to another statute or defined by SEC rule have the
meanings assigned to them by such definitions.

      SECTION 1.04. Rules of Construction. Unless the context otherwise
requires:

      (a) a term has the meaning assigned to it;

      (b) an accounting term not otherwise defined has the meaning assigned to
it in accordance with generally accepted accounting principles as in effect from
time to time;

      (c) "or" is not exclusive;

      (d) "including" means including, without limitation; and


                                       6
<PAGE>

      (e) words in the singular include the plural, and words in the plural
include the singular.

      SECTION 1.05. Acts of Holders.

      (a) Any request, demand, authorization, direction, notice, consent, waiver
or other action provided by this Indenture to be given or taken by Holders may
be embodied in and evidenced by one or more instruments of substantially similar
tenor signed by such Holders in person or by agent duly appointed in writing;
and, except as herein otherwise expressly provided, such action shall become
effective when such instrument or instruments are delivered to the Trustee and,
where it is hereby expressly required, to the Company. Such instrument or
instruments (and the action embodied therein and evidenced thereby) are herein
sometimes referred to as the "Act" of Holders signing such instrument or
instruments. Proof of execution of any such instrument or of a writing
appointing any such agent shall be sufficient for any purpose of this Indenture
and conclusive in favor of the Trustee and the Company, if made in the manner
provided in this Section.

      (b) The fact and date of the execution by any Person of any such
instrument or writing may be proved by the affidavit of a witness of such
execution or by a certificate of a notary public or other officer authorized by
law to take acknowledgments of deeds, certifying that the individual signing
such instrument or writing acknowledged to such officer the execution thereof.
Where such execution is by a signer acting in a capacity other than such
signer's individual capacity, such certificate or affidavit shall also
constitute sufficient proof of such signer's authority. The fact and date of the
execution of any such instrument or writing, or the authority of the Person
executing the same, may also be proved in any other manner which the Trustee
deems sufficient.

      (c) The ownership of Securities shall be proved by the register maintained
by the Registrar.

      (d) Any request, demand, authorization, direction, notice, consent, waiver
or other Act of the Holder of any Security shall bind every future Holder of the
same Security and the holder of every Security issued upon the registration of
transfer thereof or in exchange therefor or in lieu thereof in respect of
anything done, omitted or suffered to be done by the Trustee or the Company in
reliance thereon, whether or not notation of such action is made upon such
Security.

                                   ARTICLE II.

                                 THE SECURITIES

      SECTION 2.01. Form and Dating. The Securities and the Trustee's
certificate of authentication shall be substantially in the form of Exhibits A-1
and A-2, as the case may be, which are a part of this Indenture. The Securities
may have notations, legends or endorsements required by law, stock exchange rule
or usage (provided that any such notation, legend or endorsement required by
usage is in a form acceptable to the Company). The Company shall provide any
such notations, legends or endorsements to the Trustee in writing. Each Security
shall be dated the date of its authentication.


                                       7
<PAGE>

      (a) 144A Global Securities. Securities offered and sold within the United
States to qualified institutional buyers as defined in Rule 144A ("QIBs") in
reliance on Rule 144A shall be issued, initially in the form of a 144A Global
Security, substantially in the form of Exhibit A-1 attached hereto, which shall
be deposited with the Trustee at its Corporate Trust Offices, as custodian for
the Depositary and registered in the name of The Depository Trust Company
("DTC") or the nominee thereof (such depositary, or any successor thereto, and
any such nominee being hereinafter referred to as the "Depositary"), duly
executed by the Company and authenticated by the Trustee as hereinafter
provided. The Aggregate Principal Amount at Maturity of the 144A Global
Securities may from time to time be increased or decreased by adjustments made
on the records of the Trustee and the Depositary as hereinafter provided.

      (b) Institutional Accredited Investor Securities. Except as provided in
this Section 2.01, or in Section 2.06 or 2.12, owners of beneficial interests in
Global Securities will not be entitled to receive physical delivery of
Certificated Securities. Securities offered and sold within the United States to
institutional accredited investors as defined in Rule 501(a)(1), (2), (3) and
(7) under the Securities Act ("Institutional Accredited Investors") shall be
issued, initially in the form of an Institutional Accredited Investor Security,
duly executed by the Company and authenticated by the Trustee as hereinafter
provided.

      (c) Global Securities in General. Each Global Security shall represent
such of the outstanding Securities as shall be specified therein and each shall
provide that it shall represent the Aggregate Principal Amount at maturity of
outstanding Securities from time to time endorsed thereon and that the Aggregate
Principal Amount at Maturity of outstanding Securities represented thereby may
from time to time be reduced or increased, as appropriate, to reflect exchanges,
redemptions and conversions. Any adjustment of the Aggregate Principal Amount at
Maturity of a Global Security to reflect the amount of any increase or decrease
in the amount of outstanding Securities represented thereby shall be made by the
Trustee in accordance with instructions given by the Holder thereof as required
by Section 2.12 hereof and shall be made on the records of the Trustee and the
Depositary.

      (d) Book-Entry Provisions. This Section 2.01(d) shall apply only to Global
Securities deposited with or on behalf of the Depositary.

      The Company shall execute and the Trustee shall, in accordance with this
Section 2.01(d), authenticate and deliver initially one or more Global
Securities that (a) shall be registered in the name of the Depositary, (b) shall
be delivered by the Trustee to the Depositary or pursuant to the Depositary's
instructions and (c) shall bear legends substantially to the following effect:

      "UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF
THE DEPOSITORY TRUST COMPANY TO THE ISSUER OR ITS AGENT FOR REGISTRATION OF
TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE
NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED
REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (AND ANY PAYMENT HEREON IS MADE
TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED
REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY), ANY TRANSFER,


                                       8
<PAGE>

PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS
WRONGFUL SINCE THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.
TRANSFERS OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS, IN WHOLE BUT
NOT IN PART, TO NOMINEES OF THE DEPOSITORY TRUST COMPANY OR TO A SUCCESSOR
THEREOF OR SUCH SUCCESSOR'S NOMINEE AND TRANSFERS OF PORTIONS OF THIS GLOBAL
SECURITY SHALL BE LIMITED TO TRANSFERS MADE IN ACCORDANCE WITH THE RESTRICTIONS
SET FORTH IN ARTICLE TWO OF THE INDENTURE REFERRED TO ON THE REVERSE HEREOF."

      (e) Certificated Securities. Securities not issued as interests in the
Global Securities will be issued in certificated form substantially in the form
of Exhibit A-2 attached hereto.

      SECTION 2.02. Execution and Authentication. The Securities shall be
executed on behalf of the Company by any Officer. The signature of any of these
Officers on the Securities may be manual or facsimile.

      Securities bearing the manual or facsimile signatures of individuals who
were at the time of the execution of the Securities the proper Officers of the
Company shall bind the Company, notwithstanding that such individuals or any of
them have ceased to hold such offices prior to the authentication and delivery
of such Securities or did not hold such offices at the date of authentication of
such Securities.

      No Security shall be entitled to any benefit under this Indenture or be
valid or obligatory for any purpose unless there appears on such Security a
certificate of authentication substantially in the form provided for herein duly
executed by the Trustee by manual signature of an authorized signatory, and such
certificate upon any Security shall be conclusive evidence, and the only
evidence, that such Security has been duly authenticated and delivered
hereunder.

      The Trustee shall authenticate and deliver Securities for original issue
in an aggregate Principal Amount at Maturity of up to $195,000,000 upon a
Company Order without any further action by the Company; provided, however, that
in the event that the Company sells any Securities pursuant to the Underwriter's
over-allotment option (the "Over-Allotment Option") granted pursuant to Section
2 of the Purchase Agreement between the Company and Merrill Lynch, Pierce,
Fenner & Smith Incorporated dated as of May 1, 2001 then the Trustee shall
authenticate and deliver Securities for original issue in an aggregate Principal
Amount at Maturity of up to $195,000,000 plus up to $56,000,000 aggregate
Principal Amount at Maturity of Securities sold pursuant to the Over-Allotment
Option upon a Company Order without any further action by the Company. The
aggregate Principal Amount at Maturity of Securities outstanding at any time may
not exceed the amount set forth in the foregoing sentence, subject to the
proviso set forth therein, except as provided in Section 2.07.

      The Securities shall be issued only in registered form without coupons and
only in denominations of $1,000 of Principal Amount at Maturity and any integral
multiple thereof.

      SECTION 2.03. Registrar, Paying Agent and Conversion Agent. The Company
shall maintain an office or agency where Securities may be presented for
registration of transfer


                                       9
<PAGE>

or for exchange ("Registrar"), an office or agency where Securities may be
presented for purchase or payment ("Paying Agent") and an office or agency where
Securities may be presented for conversion ("Conversion Agent"). The Registrar
shall keep a register of the Securities and of their transfer and exchange. The
Company may have one or more co-registrars, one or more additional paying agents
and one or more additional conversion agents. The term Paying Agent includes any
additional paying agent, including any named pursuant to Section 4.05. The term
Conversion Agent includes any additional conversion agent, including any named
pursuant to Section 4.05.

      The Company shall enter into an appropriate agency agreement with any
Registrar, Paying Agent, Conversion Agent or co-registrar (other than the
Trustee). The agreement shall implement the provisions of this Indenture that
relate to the duties of such agent. The Company shall notify the Trustee of the
name and address of any such agent. If the Company fails to maintain a
Registrar, Paying Agent or Conversion Agent, the Trustee shall act as such and
shall be entitled to appropriate compensation therefor pursuant to Section 7.07.
The Company or any Subsidiary or an Affiliate of either of them may act as
Paying Agent, Registrar, Conversion Agent or co-registrar.

      The Company initially appoints the Trustee as Registrar, Conversion Agent
and Paying Agent in connection with the Securities.

      SECTION 2.04. Paying Agent to Hold Money and Securities in Trust. Except
as otherwise provided herein, on or prior to each due date of payments in
respect of any Security, the Company shall deposit with the Paying Agent a sum
of money (in immediately available funds if deposited on the due date) or, if
applicable, Common Stock sufficient to make such payments when so becoming due.
The Company shall require each Paying Agent (other than the Trustee) to agree in
writing that the Paying Agent shall hold in trust for the benefit of
Securityholders and/or the Trustee all money and Common Stock held by the Paying
Agent for the making of payments in respect of the Securities and shall notify
the Trustee of any default by the Company in making any such payment. At any
time during the continuance of any such default, the Paying Agent shall, upon
the written request of the Trustee, forthwith pay to the Trustee all money and
Common Stock so held in trust. If the Company, a Subsidiary or an Affiliate of
either of them acts as Paying Agent, it shall segregate the money and Common
Stock held by it as Paying Agent and hold it as a separate trust fund. The
Company at any time may require a Paying Agent to pay all money and Common Stock
held by it to the Trustee and to account for any funds and Common Stock
disbursed by it. Upon doing so, the Paying Agent shall have no further liability
for the money or Common Stock.

      SECTION 2.05. Securityholder Lists. The Trustee shall preserve in as
current a form as is reasonably practicable the most recent list available to it
of the names and addresses of Securityholders. If the Trustee is not the
Registrar, the Company shall cause to be furnished to the Trustee at least
semiannually on May 1 and November 1 a listing of Securityholders dated within
15 days of the date on which the list is furnished and at such other times as
the Trustee may request in writing a list in such form and as of such date as
the Trustee may reasonably require of the names and addresses of
Securityholders.


                                       10
<PAGE>

      SECTION 2.06. Transfer and Exchange. (a) Subject to Section 2.12 hereof,
upon surrender for registration of transfer of any Security, together with a
written instrument of transfer satisfactory to the Registrar duly executed by
the Securityholder or such Securityholder's attorney duly authorized in writing,
at the office or agency of the Company designated as Registrar or co-registrar
pursuant to Section 2.03, the Company shall execute, and the Trustee shall
authenticate and deliver, in the name of the designated transferee or
transferees, one or more new Securities of any authorized denomination or
denominations, of a like aggregate Principal Amount at Maturity. The Company
shall not charge a service charge for any registration of transfer or exchange,
but the Company may require payment of a sum sufficient to pay all taxes,
assessments or other governmental charges that may be imposed in connection with
the transfer or exchange of the Securities from the Securityholder requesting
such transfer or exchange.

      At the option of the Holder, Certificated Securities may be exchanged for
other Securities of any authorized denomination or denominations, of a like
aggregate Principal Amount at Maturity, upon surrender of the Securities to be
exchanged, together with a written instrument of transfer satisfactory to the
Registrar duly executed by the Securityholder or such Securityholder's attorney
duly authorized in writing, at such office or agency. Whenever any Securities
are so surrendered for exchange, the Company shall execute, and the Trustee
shall authenticate and deliver, the Securities which the Holder making the
exchange is entitled to receive.

      The Company shall not be required to make, and the Registrar need not
register, transfers or exchanges of Securities selected for redemption (except,
in the case of Securities to be redeemed in part, the portion thereof not to be
redeemed) or any Securities in respect of which a Purchase Notice or Change in
Control Purchase Notice has been given and not withdrawn by the Holder thereof
in accordance with the terms of this Indenture (except, in the case of
Securities to be purchased in part, the portion thereof not to be purchased) or
any Securities for a period of 15 days before the mailing of a notice of
redemption of Securities to be redeemed.

      (b) Notwithstanding any provision to the contrary herein, so long as a
Global Security remains outstanding and is held by or on behalf of the
Depositary, transfers of a Global Security, in whole or in part, shall be made
only in accordance with Section 2.12 and this Section 2.06(b). Transfers of a
Global Security shall be limited to transfers of such Global Security in whole,
or in part, to nominees of the Depositary or to a successor of the Depositary or
such successor's nominee.

      (c) Successive registrations and registrations of transfers and exchanges
as aforesaid may be made from time to time as desired, and each such
registration shall be noted on the register for the Securities.

      (d) Any Registrar appointed pursuant to Section 2.03 hereof shall provide
to the Trustee such information as the Trustee may reasonably require in
connection with the delivery by such Registrar of Securities upon transfer or
exchange of Securities.


                                       11
<PAGE>

      (e) No Registrar shall be required to make registrations of transfer or
exchange of Securities during any periods designated in the text of the
Securities or in this Indenture as periods during which such registration of
transfers and exchanges need not be made.

      (f) If Securities are issued upon the transfer, exchange or replacement of
Securities subject to restrictions on transfer and bearing the legends set forth
on the form of Security attached hereto as Exhibits A-1 or A-2 setting forth
such restrictions (collectively, the "Legend"), or if a request is made to
remove the Legend on a Security, the Securities so issued shall bear the Legend,
or the Legend shall not be removed, as the case may be, unless (i) there is
delivered to the Company and the Registrar such satisfactory evidence, which
shall include an Opinion of Counsel, as may be reasonably required by the
Company and the Registrar, that neither the Legend nor the restrictions on
transfer set forth therein are required to ensure that transfers thereof comply
with the provisions of Rule 144A or Rule 144 under the Securities Act or that
such Securities are not "restricted" within the meaning of Rule 144 under the
Securities Act. Upon (i) provision of such satisfactory evidence, or (ii)
notification by the Company to the Trustee and Registrar of the sale of such
Security pursuant to a registration statement that is effective at the time of
such sale, the Trustee, at the written direction of the Company, shall
authenticate and deliver a Security that does not bear the Legend. If the Legend
is removed from the face of a Security and the Security is subsequently held by
an Affiliate of the Company, the Legend shall be reinstated.

      SECTION 2.07. Replacement Securities. If (a) any mutilated Security is
surrendered to the Trustee, or (b) the Company and the Trustee receive evidence
to their satisfaction of the destruction, loss or theft of any Security, and
there is delivered to the Company and the Trustee such security or indemnity as
may be required by them to save each of them harmless, then, in the absence of
notice to the Company or the Trustee that such Security has been acquired by a
bona fide purchaser, the Company shall execute and upon its written request the
Trustee shall authenticate and deliver, in exchange for any such mutilated
Security or in lieu of any such destroyed, lost or stolen Security, a new
Security of like tenor and Principal Amount at Maturity, bearing a number not
contemporaneously outstanding.

      In case any such mutilated, destroyed, lost or stolen Security has become
or is about to become due and payable, or is about to be purchased by the
Company pursuant to Article 3 hereof, the Company in its discretion may, instead
of issuing a new Security, pay or purchase such Security, as the case may be.

      Upon the issuance of any new Securities under this Section, the Company
may require the payment of a sum sufficient to cover any tax or other
governmental charge that may be imposed in relation thereto and any other
expenses (including the fees and expenses of the Trustee) connected therewith.

      Every new Security issued pursuant to this Section in lieu of any
mutilated, destroyed, lost or stolen Security shall constitute an original
additional contractual obligation of the Company, whether or not the mutilated,
destroyed, lost or stolen Security shall be at any time enforceable by anyone,
and shall be entitled to all benefits of this Indenture equally and
proportionately with any and all other Securities duly issued hereunder.


                                       12
<PAGE>

      The provisions of this Section are exclusive and shall preclude (to the
extent lawful) all other rights and remedies with respect to the replacement or
payment of mutilated, destroyed, lost or stolen Securities.

      SECTION 2.08. Outstanding Securities; Determinations of Holders' Action.
Securities outstanding at any time are all the Securities authenticated by the
Trustee except for those canceled by it, those delivered to it for cancellation,
those paid pursuant to Section 2.07 and those described in this Section 2.08 as
not outstanding. A Security does not cease to be outstanding because the Company
or an Affiliate thereof holds the Security; provided, however, that in
determining whether the Holders of the requisite Principal Amount at Maturity of
Securities have given or concurred in any request, demand, authorization,
direction, notice, consent or waiver hereunder, Securities owned by the Company
or any other obligor upon the Securities or any Affiliate of the Company or such
other obligor shall be disregarded and deemed not to be outstanding, except
that, in determining whether the Trustee shall be protected in relying upon any
such request, demand, authorization, direction, notice, consent or waiver, only
Securities which a Responsible Officer of the Trustee actually knows to be so
owned shall be so disregarded. Subject to the foregoing, only Securities
outstanding at the time of such determination shall be considered in any such
determination (including, without limitation, determinations pursuant to
Articles 6 and 9).

      If a Security is replaced pursuant to Section 2.07, it ceases to be
outstanding unless the Trustee receives proof satisfactory to it that the
replaced Security is held by a bona fide purchaser.

      If the Paying Agent holds, in accordance with this Indenture, on a
Redemption Date, or on the Business Day following the Purchase Date or a Change
in Control Purchase Date, or on Stated Maturity, money or securities, if
permitted hereunder, sufficient to pay Securities payable on that date, then
immediately after such Redemption Date, Purchase Date, Change in Control
Purchase Date or Stated Maturity, as the case may be, such Securities shall
cease to be outstanding and Original Issue Discount and interest, if any, on
such Securities shall cease to accrue; provided, that if such Securities are to
be redeemed, notice of such redemption has been duly given pursuant to this
Indenture or provision therefor satisfactory to the Trustee has been made.

      If a Security is converted in accordance with Article 11, then from and
after the time of conversion on the Conversion Date, such Security shall cease
to be outstanding and Original Issue Discount and interest, if any, shall cease
to accrue on such Security.

      SECTION 2.09. Temporary Securities. Pending the preparation of definitive
Securities, the Company may execute, and upon Company Order the Trustee shall
authenticate and deliver, temporary Securities which are printed, lithographed,
typewritten, mimeographed or otherwise produced, in any authorized denomination,
substantially of the tenor of the definitive Securities in lieu of which they
are issued and with such appropriate insertions, omissions, substitutions and
other variations as the officers executing such Securities may determine, as
conclusively evidenced by their execution of such Securities.


                                       13
<PAGE>

      If temporary Securities are issued, the Company will cause definitive
Securities to be prepared without unreasonable delay. After the preparation of
definitive Securities, the temporary Securities shall be exchangeable for
definitive Securities upon surrender of the temporary Securities at the office
or agency of the Company designated for such purpose pursuant to Section 2.03,
without charge to the Holder. Upon surrender for cancellation of any one or more
temporary Securities the Company shall execute and the Trustee shall
authenticate and deliver in exchange therefor a like Principal Amount at
Maturity of definitive Securities of authorized denominations. Until so
exchanged the temporary Securities shall in all respects be entitled to the same
benefits under this Indenture as definitive Securities.

      SECTION 2.10. Cancellation. All Securities surrendered for payment,
purchase by the Company pursuant to Article 3, conversion, redemption or
registration of transfer or exchange shall, if surrendered to any person other
than the Trustee, be delivered to the Trustee and shall be promptly canceled by
it. The Company may at any time deliver to the Trustee for cancellation any
Securities previously authenticated and delivered hereunder which the Company
may have acquired in any manner whatsoever, and all Securities so delivered
shall be promptly canceled by the Trustee. The Company may not issue new
Securities to replace Securities it has paid or delivered to the Trustee for
cancellation or that any Holder has converted pursuant to Article 11. No
Securities shall be authenticated in lieu of or in exchange for any Securities
canceled as provided in this Section, except as expressly permitted by this
Indenture. All canceled Securities held by the Trustee shall be disposed of by
the Trustee in accordance with its customary practice.

      SECTION 2.11. Persons Deemed Owners. Prior to due presentment of a
Security for registration of transfer, the Company, the Trustee and any agent of
the Company or the Trustee may treat the Person in whose name such Security is
registered as the owner of such Security for the purpose of receiving payment of
principal of the Security or the payment of any Redemption Price, Purchase Price
or Change in Control Purchase Price in respect thereof, and interest thereon,
for the purpose of conversion and for all other purposes whatsoever, whether or
not such Security be overdue, and neither the Company, the Trustee nor any agent
of the Company or the Trustee shall be affected by notice to the contrary.

      SECTION 2.12. Global Securities.

      (a) Notwithstanding any other provisions of this Indenture or the
Securities, (A) transfers of a Global Security, in whole or in part, shall be
made only in accordance with Section 2.06 and Section 2.12(a)(i), (B) transfer
of a beneficial interest in a Global Security for a Certificated Security shall
comply with Section 2.06 and Section 2.12(a)(ii) below, and (C) transfers of a
Certificated Security shall comply with Section 2.06 and Section 2.12(a)(iii)
and (iv) below.

            (i) Transfer of Global Security. A Global Security may not be
      transferred, in whole or in part, to any Person other than the Depositary
      or a nominee or any successor thereof, and no such transfer to any such
      other Person may be registered; provided that this clause (i) shall not
      prohibit any transfer of a Security that is issued in exchange for a
      Global Security but is not itself a Global Security. No transfer of a
      Security to any Person shall be effective under this Indenture or the
      Securities unless and until such Security has been registered in the name
      of such Person. Nothing in this Section 2.12(a)(i) shall


                                       14
<PAGE>

      prohibit or render ineffective any transfer of a beneficial interest in a
      Global Security effected in accordance with the other provisions of this
      Section 2.12(a).

            (ii) Restrictions on Transfer of a Beneficial Interest in a Global
      Security for a Certificated Security. A beneficial interest in a Global
      Security may not be exchanged for a Certificated Security except upon
      satisfaction of the requirements set forth below. Upon receipt by the
      Trustee of a transfer of a beneficial interest in a Global Security in
      accordance with Applicable Procedures for a Certificated Security in the
      form satisfactory to the Trustee, together with:

                  (a) so long as the Securities are Restricted Securities,
      certification, in the form set forth in Exhibit B-1;

                  (b) if such beneficial interest in the Global Security is
      being transferred to an Institutional Accredited Investor in accordance
      with Sections 501(a)(1), (2), (3) or (7) of the Securities Act,
      certification in the form set forth in Exhibit B-2;

                  (c) if a Restricted Security is being transferred (i) to an
      "institutional accredited investor" within the meaning of Rule 501(a)(1),
      (2), (3) or (7) under the Securities Act that is acquiring the Security
      for its own account, or for the account of such an institutional
      accredited investor for investment purposes and not with a view to, or for
      offer or sale in connection with, any distribution in violation of the
      Securities Act, (ii) in an offshore transaction in accordance with Rule
      904 of Regulation S under the Securities Act or (iii) in reliance on
      another exemption from the registration requirements of the Securities
      Act, an opinion of counsel, certification and/or other information
      satisfactory to the Company and the Trustee; and

                  (d) written instructions to the Trustee to make, or direct the
      Registrar to make, an adjustment on its books and records with respect to
      such Global Security to reflect a decrease in the aggregate Principal
      Amount at Maturity of the Securities represented by the Global Security,
      such instructions to contain information regarding the Depositary account
      to be credited with such decrease,

then the Trustee shall cause, or direct the Registrar to cause, in accordance
with the standing instructions and procedures existing between the Depositary
and the Registrar, the aggregate Principal Amount at Maturity of Securities
represented by the Global Security to be decreased by the aggregate Principal
Amount at Maturity of the Certificated Security to be issued, shall authenticate
and deliver such Certificated Security and shall debit or cause to be debited to
the account of the Person specified in such instructions a beneficial interest
in the Global Security equal to the Principal Amount at Maturity of the
Certificated Security so issued.

            (iii) Transfer and Exchange of Certificated Securities. When
      Certificated Securities are presented to the Registrar with a request:

                  (x) to register the transfer of such Certificated Securities;
                  or

                  (y) to exchange such Certificated Securities for an equal
                  Principal Amount at Maturity of Certificated Securities of
                  other authorized denominations,


                                       15
<PAGE>

the Registrar shall register the transfer or make the exchange as requested if
its reasonable requirements for such transaction are met; provided, however,
that the Certificated Securities surrendered for transfer or exchange:

            (a) shall be duly endorsed or accompanied by a written instrument of
      transfer in form reasonably satisfactory to the Company and the Registrar,
      duly executed by the Holder thereof or his attorney duly authorized in
      writing; and

            (b) so long as such Securities are Restricted Securities, such
      Securities are being transferred or exchanged pursuant to an effective
      registration statement under the Securities Act or pursuant to clause (A),
      (B) or (C) below, and are accompanied by the following additional
      information and documents, as applicable:

                  (A) if such Certificated Securities are being delivered to the
            Registrar by a Holder for registration in the name of such Holder,
            without transfer, a certification from such Holder to that effect;
            or

                  (B) if such Certificated Securities are being transferred to
            the Company, a certification to that effect; or

                  (C) if such Certificated Security is being transferred to an
            Institutional Accredited Investor in accordance with Sections
            501(a)(1), (2), (3) or (7) of the Securities Act, certification in
            the form set forth in Exhibit B-2; or

                  (D) if a Certificated Security is being transferred (i) to an
            "institutional accredited investor" within the meaning of Rule
            501(a)(1), (2), (3) or (7) under the Securities Act that is
            acquiring the Security for its own account, or for the account of
            such an institutional accredited investor for investment purposes
            and not with a view to, or for offer or sale in connection with, any
            distribution in violation of the Securities Act, (ii) in an offshore
            transaction in accordance with Rule 904 of Regulation S under the
            Securities Act or (iii) in reliance on another exemption from the
            registration requirements of the Securities Act, an opinion of
            counsel, certification and/or other information satisfactory to the
            Company and the Trustee.

            (iv) Restrictions on Transfer of a Certificated Security for a
      Beneficial Interest in a Global Security. A Certificated Security may not
      be exchanged for a beneficial interest in a Global Security except upon
      satisfaction of the requirements set forth below. Upon receipt by the
      Trustee of a Certificated Security, duly endorsed or accompanied by
      appropriate instruments of transfer, in form satisfactory to the Trustee,
      together with:

                  (a) so long as the Securities are Restricted Securities,
      certification, in the form set forth in Exhibit B-1, that such
      Certificated Security is being transferred to a QIB in accordance with
      Rule 144A; and

                  (b) written instructions directing the Trustee to make, or to
      direct the Registrar to make, an adjustment on its books and records with
      respect to such Global Security to reflect an increase in the aggregate
      Principal Amount at Maturity of the Securities


                                       16
<PAGE>

      represented by the Global Security, such instructions to contain
      information regarding the Depositary account to be credited with such
      increase,

      then the Trustee shall cancel such Certificated Security and cause, or
      direct the Registrar to cause, in accordance with the standing
      instructions and procedures existing between the Depositary and the
      Registrar, the aggregate Principal Amount at Maturity of Securities
      represented by the Global Security to be increased by the aggregate
      Principal Amount at Maturity of the Certificated Security to be exchanged,
      and shall credit or cause to be credited to the account of the Person
      specified in such instructions a beneficial interest in the Global
      Security equal to the Principal Amount at Maturity of the Certificated
      Security so canceled. If no Global Securities are then outstanding, the
      Company shall issue and the Trustee shall authenticate, upon written order
      of the Company in the form of an Officers' Certificate, a new Global
      Security in the appropriate Principal Amount at Maturity.

      (b) Subject to the succeeding paragraph, every Security shall be subject
to the restrictions on transfer provided in the Legend. Whenever any Restricted
Security is presented or surrendered for registration of transfer or for
exchange for a Security registered in a name other than that of the Holder, such
Security must be accompanied by a certificate in substantially the form set
forth in Exhibit B-1, dated the date of such surrender and signed by the Holder
of such Security, as to compliance with such restrictions on transfer. The
Registrar shall not be required to accept for such registration of transfer or
exchange any Security not so accompanied by a properly completed certificate.

      (c) The restrictions imposed by the Legend upon the transferability of any
Security shall cease and terminate when such Security has been sold pursuant to
an effective registration statement under the Securities Act or transferred in
compliance with Rule 144 under the Securities Act (or any successor provision
thereto) or, if earlier, upon the expiration of the holding period applicable to
sales thereof under Rule 144(k) under the Securities Act (or any successor
provision). Any Security as to which such restrictions on transfer shall have
expired in accordance with their terms or shall have terminated may, upon a
surrender of such Security for exchange to the Registrar in accordance with the
provisions of this Section 2.12 (accompanied, in the event that such
restrictions on transfer have terminated by reason of a transfer in compliance
with Rule 144 or any successor provision, by an opinion of counsel having
substantial experience in practice under the Securities Act and otherwise
reasonably acceptable to the Company, addressed to the Company and in form
acceptable to the Company, to the effect that the transfer of such Security has
been made in compliance with Rule 144 or such successor provision), be exchanged
for a new Security, of like tenor and aggregate Principal Amount at Maturity,
which shall not bear the restrictive Legend. The Company shall inform the
Trustee of the effective date of any registration statement registering the
Securities under the Securities Act. The Trustee shall not be liable for any
action taken or omitted to be taken by it in good faith in accordance with the
aforementioned opinion of counsel or registration statement.

      (d) As used in the preceding two paragraphs of this Section 2.12, the term
"transfer" encompasses any sale, pledge, transfer, hypothecation or other
disposition of any Security.


                                       17
<PAGE>

      (e) The provisions of clauses (1), (2), (3) and (4) below shall apply only
to Global Securities:

            (1) Notwithstanding any other provisions of this Indenture or the
      Securities, except as provided in Section 2.12(a)(ii), a Global Security
      shall not be exchanged in whole or in part for a Security registered in
      the name of any Person other than the Depositary or one or more nominees
      thereof, provided that a Global Security may be exchanged for Securities
      registered in the names of any person designated by the Depositary in the
      event that (i) the Depositary has notified the Company that it is
      unwilling or unable to continue as Depositary for such Global Security or
      such Depositary has ceased to be a "clearing agency" registered under the
      Exchange Act, and a successor Depositary is not appointed by the Company
      within 90 days or (ii) an Event of Default has occurred and is continuing
      with respect to the Securities. Any Global Security exchanged pursuant to
      clause (i) above shall be so exchanged in whole and not in part, and any
      Global Security exchanged pursuant to clause (ii) above may be exchanged
      in whole or from time to time in part as directed by the Depositary. Any
      Security issued in exchange for a Global Security or any portion thereof
      shall be a Global Security; provided that any such Security so issued that
      is registered in the name of a Person other than the Depositary or a
      nominee thereof shall not be a Global Security.

            (2) Securities issued in exchange for a Global Security or any
      portion thereof shall be issued in definitive, fully registered form,
      without interest coupons, shall have an aggregate Principal Amount at
      Maturity equal to that of such Global Security or portion thereof to be so
      exchanged, shall be registered in such names and be in such authorized
      denominations as the Depositary shall designate and shall bear the
      applicable legends provided for herein. Any Global Security to be
      exchanged in whole shall be surrendered by the Depositary to the Trustee,
      as Registrar. With regard to any Global Security to be exchanged in part,
      either such Global Security shall be so surrendered for exchange or, if
      the Trustee is acting as custodian for the Depositary or its nominee with
      respect to such Global Security, the Principal Amount at Maturity thereof
      shall be reduced, by an amount equal to the portion thereof to be so
      exchanged, by means of an appropriate adjustment made on the records of
      the Trustee. Upon any such surrender or adjustment, the Trustee shall
      authenticate and deliver the Security issuable on such exchange to or upon
      the order of the Depositary or an authorized representative thereof.

            (3) Subject to the provisions of clause (5) below, the registered
      Holder may grant proxies and otherwise authorize any Person, including
      Agent Members and persons that may hold interests through Agent Members,
      to take any action which a holder is entitled to take under this Indenture
      or the Securities.

            (4) In the event of the occurrence of any of the events specified in
      clause (1) above, the Company will promptly make available to the Trustee
      a reasonable supply of Certificated Securities in definitive, fully
      registered form, without interest coupons.

            (5) Neither any members of, or participants in, the Depositary
      ("Agent Members") nor any other Persons on whose behalf Agent Members may
      act shall have any rights under this Indenture with respect to any Global
      Security registered in the name


                                       18
<PAGE>

      of the Depositary or any nominee thereof, or under any such Global
      Security, and the Depositary or such nominee, as the case may be, may be
      treated by the Company, the Trustee and any agent of the Company or the
      Trustee as the absolute owner and holder of such Global Security for all
      purposes whatsoever. Notwithstanding the foregoing, nothing herein shall
      prevent the Company, the Trustee or any agent of the Company or the
      Trustee from giving effect to any written certification, proxy or other
      authorization furnished by the Depositary or such nominee, as the case may
      be, or impair, as between the Depositary, its Agent Members and any other
      person on whose behalf an Agent Member may act, the operation of customary
      practices of such Persons governing the exercise of the rights of a holder
      of any Security.

            (6) The Trustee shall have no obligation or duty to monitor,
      determine or inquire as to compliance with any restrictions on transfer
      imposed under this Indenture or under applicable law with respect to any
      transfer of any interest in any Security (including any transfers between
      or among Agent members or beneficial owners of interests in any Global
      Security) other than to require delivery of such certificates and other
      documentation or evidence as are expressly required by, and to do so if
      and when expressly required by the terms of, this Indenture, and to
      examine the same to determine substantial compliance as to form with the
      express requirements hereof.

      SECTION 2.13. CUSIP Numbers. The Company in issuing the Securities may use
"CUSIP" numbers (if then generally in use), and, if so, the Trustee shall use
"CUSIP" numbers in notices of redemption as a convenience to Holders; provided
that any such notice may state that no representation is made as to the
correctness of such numbers either as printed on the Securities or as contained
in any notice of a redemption and that reliance may be placed only on the other
identification numbers printed on the Securities, and any such redemption shall
not be affected by any defect in or omission of such numbers. The Company will
promptly notify the Trustee of any change in the CUSIP numbers.

                                  ARTICLE III.

                            REDEMPTION AND PURCHASES

      SECTION 3.01. Right to Redeem; Notices to Trustee. The Company, at its
option, may redeem the Securities in accordance with the provisions of
paragraphs 5 and 7 of the Securities. If the Company elects to redeem Securities
pursuant to paragraph 5 of the Securities, it shall notify the Trustee in
writing of the Redemption Date, the Principal Amount at Maturity of Securities
to be redeemed and the Redemption Price.

      The Company shall give the notice to the Trustee provided for in this
Section 3.01 by a Company Order, at least 25 days before the Redemption Date,
unless a shorter notice shall be satisfactory to the Trustee).

      SECTION 3.02. Selection of Securities to Be Redeemed. If less than all the
Securities are to be redeemed, the Trustee shall select the Securities to be
redeemed pro rata or by lot or by any other method the Trustee considers fair
and appropriate (so long as such method


                                       19
<PAGE>

is not prohibited by the rules of any stock exchange on which the Securities are
then listed). The Trustee shall make the selection at least 15 days but not more
than 60 days before the Redemption Date from outstanding Securities not
previously called for redemption. The Trustee may select for redemption portions
of the Principal Amount at Maturity of Securities that have denominations larger
than $1,000. Securities and portions of them the Trustee selects shall be in
Principal Amounts at Maturity of $1,000 or an integral multiple of $1,000.
Provisions of this Indenture that apply to Securities called for redemption also
apply to portions of Securities called for redemption. The Trustee shall notify
the Company promptly of the Securities or portions of Securities to be redeemed.

      If any Security selected for partial redemption is converted in part
before termination of the conversion right with respect to the portion of the
Security so selected, the converted portion of such Security shall be deemed (so
far as may be) to be the portion selected for redemption. Securities which have
been converted during a selection of Securities to be redeemed may be treated by
the Trustee as outstanding for the purpose of such selection.

      SECTION 3.03. Notice of Redemption. At least 15 days but not more than 60
days before a Redemption Date, the Company shall mail a notice of redemption by
first-class mail, postage prepaid, to each Holder of Securities to be redeemed.

      The notice shall identify the Securities to be redeemed and shall at a
minimum state:

      (a) the Redemption Date;

      (b) the Redemption Price;

      (c) the Conversion Rate;

      (d) the name and address of the Paying Agent and Conversion Agent;

      (e) that Securities called for redemption may be converted at any time
before the close of business on the second Business Day immediately preceding
the Redemption Date;

      (f) that Holders who want to convert Securities must satisfy the
requirements set forth in paragraph 8 of the Securities;

      (g) that Securities called for redemption must be surrendered to the
Paying Agent to collect the Redemption Price;

      (h) if fewer than all the outstanding Securities are to be redeemed, the
certificate number and Principal Amounts at Maturity of the particular
Securities to be redeemed;

      (i) that, unless the Company defaults in making payment of such Redemption
Price, Original Issue Discount and interest, if any, on Securities called for
redemption, and interest, if any, will cease to accrue on and after the
Redemption Date; and

      (j) the CUSIP number of the Securities.


                                       20
<PAGE>

      At the Company's request, the Trustee shall give the notice of redemption
in the Company's name and at the Company's expense, provided that the Company
makes such request at least three Business Days prior to such notice of
redemption.

      SECTION 3.04. Effect of Notice of Redemption. Once notice of redemption is
given, Securities called for redemption become due and payable on the Redemption
Date and at the Redemption Price stated in the notice except for Securities
which are converted in accordance with the terms of this Indenture. Upon
surrender to the Paying Agent, such Securities shall be paid at the Redemption
Price stated in the notice.

      SECTION 3.05. Deposit of Redemption Price. Prior to 10:00 a.m., New York
City time on the Redemption Date, the Company shall deposit with the Paying
Agent (or if the Company or a Subsidiary or an Affiliate of either of them is
the Paying Agent, shall segregate and hold in trust) money sufficient to pay the
Redemption Price, together with interest, if any, accrued and unpaid to the
Redemption Date, of all Securities to be redeemed on that date other than
Securities or portions of Securities called for redemption which on or prior
thereto have been delivered by the Company to the Trustee for cancellation or
have been converted. The Paying Agent shall as promptly as practicable return to
the Company any money not required for that purpose because of conversion of
Securities pursuant to Article 11. If such money is then held by the Company in
trust and is not required for such purpose it shall be discharged from such
trust.

      SECTION 3.06. Securities Redeemed in Part. Upon surrender of a Security
that is redeemed in part, the Company shall execute and the Trustee shall
authenticate and deliver to the Holder a new Security in an authorized
denomination equal in Principal Amount at Maturity to the unredeemed portion of
the Security surrendered.

      SECTION 3.07. Conversion Arrangement on Call for Redemption. In connection
with any redemption of Securities, the Company may arrange for the purchase and
conversion of any Securities called for redemption by an agreement with one or
more investment banks or other purchasers to purchase such Securities by paying
to the Trustee in trust for the Securityholders, on or prior to 10:00 a.m., New
York City time on the Redemption Date, an amount that, together with any amounts
deposited with the Trustee by the Company for the redemption of such Securities,
is not less than the Redemption Price, together with interest, if any, accrued
and unpaid to the Redemption Date, of such Securities. Notwithstanding anything
to the contrary contained in this Article 3, the obligation of the Company to
pay the Redemption Price of such Securities, including all accrued interest, if
any, shall be deemed to be satisfied and discharged to the extent such amount is
so paid by such purchasers. If such an agreement is entered into, any Securities
not duly surrendered for conversion by the Holders thereof may, at the option of
the Company, be deemed, to the fullest extent permitted by law, acquired by such
purchasers from such Holders and (notwithstanding anything to the contrary
contained in Article 11) surrendered by such purchasers for conversion, all as
of immediately prior to the close of business on the Business Day prior to the
Redemption Date, subject to payment of the above amount as aforesaid. The
Trustee shall hold and pay to the Holders whose Securities are selected for
redemption any such amount paid to it for purchase and conversion in the same
manner as it would moneys deposited with it by the Company for the redemption of
Securities. Without the Trustee's prior written consent, no arrangement between
the Company and such purchasers for


                                       21
<PAGE>

the purchase and conversion of any Securities shall increase or otherwise affect
any of the powers, duties, responsibilities or obligations of the Trustee as set
forth in this Indenture, and the Company agrees to indemnify the Trustee from,
and hold it harmless against, any loss, liability or expense arising out of or
in connection with any such arrangement for the purchase and conversion of any
Securities between the Company and such purchasers, including the costs and
expenses incurred by the Trustee in the defense of any claim or liability
arising out of or in connection with the exercise or performance of any of its
powers, duties, responsibilities or obligations under this Indenture.

      SECTION 3.08. Purchase of Securities at Option of the Holder.

      (a) General. Securities shall be purchased by the Company pursuant to
paragraph 6 of the Securities as of May 7, 2002, May 7, 2004, May 7, 2006, May
7, 2011 and May 7, 2016 (each, a "Purchase Date"), at the purchase price
specified therein (each, a "Purchase Price"), at the option of the Holder
thereof, upon:

            (1) delivery to the Paying Agent, by the Holder of a written notice
      of purchase (a "Purchase Notice") at any time from the opening of business
      on the date that is 30 Business Days prior to a Purchase Date until the
      close of business on such Purchase Date stating:

                  (A) the certificate number of the Security which the Holder
            will deliver to be purchased,

                  (B) the portion of the Principal Amount at Maturity of the
            Security which the Holder will deliver to be purchased, which
            portion must be in a Principal Amount at Maturity of $1,000 or an
            integral multiple thereof,

                  (C) that such Security shall be purchased as of the Purchase
            Date pursuant to the terms and conditions specified in paragraph 6
            of the Securities and in this Indenture, and

                  (D) in the event the Company elects, pursuant to Section
            3.08(b), to pay the Purchase Price to be paid as of such Purchase
            Date, in whole or in part, in shares of Common Stock but such
            portion of the Purchase Price shall ultimately be payable to such
            Holder entirely in cash because any of the conditions to payment of
            the Purchase Price in Common Stock is not satisfied prior to the
            close of business on such Purchase Date, as set forth in Section
            3.08(d), whether such Holder elects (i) to withdraw such Purchase
            Notice as to some or all of the Securities to which such Purchase
            Notice relates (stating the Principal Amount at Maturity and
            certificate numbers of the Securities as to which such withdrawal
            shall relate), or (ii) to receive cash in respect of the entire
            Purchase Price for all Securities (or portions thereof) to which
            such Purchase Notice relates; and

            (2) delivery of such Security to the Paying Agent prior to, on or
      after the Purchase Date (together with all necessary endorsements) at the
      offices of the Paying Agent, such delivery being a condition to receipt by
      the Holder of the Purchase Price therefor; provided, however, that such
      Purchase Price shall be so paid pursuant to this Section 3.08


                                       22
<PAGE>

      only if the Security so delivered to the Paying Agent shall conform in all
      respects to the description thereof in the related Purchase Notice, as
      determined by the Company.

      If a Holder, in such Holder's Purchase Notice and in any written notice of
withdrawal delivered by such Holder pursuant to the terms of Section 3.10, fails
to indicate such Holder's choice with respect to the election set forth in
clause (D) of Section 3.08(a)(1), such Holder shall be deemed to have elected to
receive cash in respect of the Purchase Price for all Securities subject to such
Purchase Notice in the circumstances set forth in such clause (D).

      The Company shall purchase from the Holder thereof, pursuant to this
Section 3.08, a portion of a Security if the Principal Amount at Maturity of
such portion is $1,000 or an integral multiple of $1,000. Provisions of this
Indenture that apply to the purchase of all of a Security also apply to the
purchase of such portion of such Security.

      Any purchase by the Company contemplated pursuant to the provisions of
this Section 3.08 shall be consummated by the delivery of the consideration to
be received by the Holder promptly following the later of the Purchase Date and
the time of delivery of the Security to the Paying Agent in accordance with this
Section 3.08.

      Notwithstanding anything herein to the contrary, any Holder delivering to
the Paying Agent the Purchase Notice contemplated by this Section 3.08(a) shall
have the right to withdraw such Purchase Notice at any time prior to the close
of business on the Purchase Date by delivery of a written notice of withdrawal
to the Paying Agent in accordance with Section 3.10.

      The Paying Agent shall promptly notify the Company of the receipt by it of
any Purchase Notice or written notice of withdrawal thereof.

      (b) Company's Right to Elect Manner of Payment of Purchase Price. The
Securities to be purchased pursuant to Section 3.08(a) may be paid for, at the
election of the Company, in U.S. legal tender ("cash") or Common Stock, or in
any combination of cash and Common Stock, subject to the conditions set forth in
Sections 3.08(c) and (d). The Company shall designate, in the Company Notice
delivered pursuant to Section 3.08(e), whether the Company will purchase the
Securities for cash or Common Stock, or, if a combination thereof, the
percentages of the Purchase Price of Securities in respect of which it will pay
in cash or Common Stock; provided that the Company will pay cash for fractional
interests in Common Stock. For purposes of determining the existence of
potential fractional interests, all Securities subject to purchase by the
Company held by a Holder shall be considered together (no matter how many
separate certificates are to be presented). Each Holder whose Securities are
purchased pursuant to this Section 3.08 shall receive the same percentage of
cash or Common Stock in payment of the Purchase Price for such Securities,
except (i) as provided in Section 3.08(d) with regard to the payment of cash in
lieu of fractional shares of Common Stock and (ii) in the event that the Company
is unable to purchase the Securities of a Holder or Holders for Common Stock
because any necessary qualifications or registrations of the Common Stock under
applicable state securities laws cannot be obtained, the Company may purchase
the Securities of such Holder or Holders for cash. The Company may not change
its election with respect to the consideration (or components or percentages of
components thereof) to be paid once the Company has given its Company Notice to
Securityholders except pursuant to this Section 3.08(b) or pursuant to


                                       23
<PAGE>

Section 3.08(d) in the event of a failure to satisfy, prior to the close of
business on the Purchase Date, any condition to the payment of the Purchase
Price, in whole or in part, in Common Stock.

      At least three Business Days before the Company Notice Date, the Company
shall deliver an Officers' Certificate to the Trustee specifying:

            (i) the manner of payment selected by the Company,

            (ii) the information required by Section 3.08(e),

            (iii) if the Company elects to pay the Purchase Price, or a
      specified percentage thereof, in Common Stock, that the conditions to such
      manner of payment set forth in Section 3.08(d) have been or will be
      complied with, and

            (iv) whether the Company desires the Trustee to give the Company
      Notice required by Section 3.08(e).

      (c) Purchase with Cash. On each Purchase Date, at the option of the
Company, the Purchase Price of Securities in respect of which a Purchase Notice
pursuant to Section 3.08(a) has been given, or a specified percentage thereof,
may be paid by the Company with cash equal to the aggregate Purchase Price of
such Securities. If the Company elects to purchase Securities with cash, the
Company Notice, as provided in Section 3.08(e), shall be sent to Holders (and to
beneficial owners as required by applicable law) not less than 20 Business Days
prior to such Purchase Date (the "Company Notice Date").

      (d) Payment by Issuance of Common Stock. On each Purchase Date, at the
option of the Company, the Purchase Price of Securities in respect of which a
Purchase Notice pursuant to Section 3.08(a) has been given, or a specified
percentage thereof, may be paid by the Company by the issuance of a number of
shares of Common Stock equal to the quotient obtained by dividing (i) the amount
of cash to which the Securityholders would have been entitled had the Company
elected to pay all or such specified percentage, as the case may be, of the
Purchase Price of such Securities in cash by (ii) the Market Price of a share of
Common Stock, subject to the next succeeding paragraph.

      The Company will not issue a fractional share of Common Stock in payment
of the Purchase Price. Instead the Company will pay cash for the current market
value of the fractional share. The current market value of a fraction of a share
shall be determined by multiplying the Market Price by such fraction and
rounding the product to the nearest whole cent. It is understood that if a
Holder elects to have more than one Security purchased, the number of shares of
Common Stock shall be based on the aggregate amount of Securities to be
purchased.

      If the Company elects to purchase the Securities by the issuance of shares
of Common Stock, the Company Notice, as provided in Section 3.08(e), shall be
sent to the Holders (and to beneficial owners as required by applicable law) not
later than the Company Notice Date.

      The Company's right to exercise its election to purchase the Securities
pursuant to Section 3.08 through the issuance of shares of Common Stock shall be
conditioned upon:


                                       24
<PAGE>

            (i) the Company's not having given its Company Notice of an election
      to pay entirely in cash and its giving of timely Company Notice of
      election to purchase all or a specified percentage of the Securities with
      Common Stock as provided herein;

            (ii) the registration of the shares of Common Stock to be issued in
      respect of the payment of the Purchase Price under the Securities Act of
      1933, as amended (the "Securities Act"), or the Securities Exchange Act of
      1934, as amended (the "Exchange Act"), in each case, if required;

            (iii) any necessary qualification or registration under applicable
      state securities laws or the availability of an exemption from such
      qualification and registration; and

            (iv) the receipt by the Trustee of an Officers' Certificate and an
      Opinion of Counsel each stating that (A) the terms of the issuance of the
      Common Stock are in conformity with this Indenture and (B) the shares of
      Common Stock to be issued by the Company in payment of the Purchase Price
      in respect of Securities have been duly authorized and, when issued and
      delivered pursuant to the terms of this Indenture in payment of the
      Purchase Price in respect of the Securities, will be validly issued, fully
      paid and non-assessable and, to the best of such counsel's knowledge, free
      from preemptive rights, and, in the case of such Officers' Certificate,
      stating that conditions (i), (ii) and (iii) above and the condition set
      forth in the second succeeding sentence have been satisfied and, in the
      case of such Opinion of Counsel, stating that conditions (ii) and (iii)
      above have been satisfied.

Such Officers' Certificate shall also set forth the number of shares of Common
Stock to be issued for each $1,000 Principal Amount at Maturity of Securities
and the Sale Price of a share of Common Stock on each trading day during the
period commencing on the first trading day of the period during which the Market
Price is calculated and ending on the applicable Purchase Date. The Company may
pay the Purchase Price (or any portion thereof) in Common Stock only if the
information necessary to calculate the Market Price is published in a daily
newspaper of national circulation. If the foregoing conditions are not satisfied
with respect to a Holder or Holders prior to the close of business on the
Purchase Date and the Company has elected to purchase the Securities pursuant to
this Section 3.08 through the issuance of shares of Common Stock, the Company
shall pay the entire Purchase Price of the Securities of such Holder or Holders
in cash.

      The "Market Price" means the average of the Sale Prices of the Common
Stock for the five trading day period ending on (if the third Business Day prior
to the applicable Purchase Date is a trading day, or if not, then on the last
trading day prior to) the third Business Day prior to the applicable Purchase
Date, appropriately adjusted to take into account the occurrence, during the
period commencing on the first of such trading days during such five trading day
period and ending on such Purchase Date, of any event described in Section
11.06, 11.07 or 11.08; subject, however, to the conditions set forth in Sections
11.09 and 11.10.

      The "Sale Price" of the Common Stock on any date means the closing per
share sale price (or, if no closing sale price is reported, the average of the
bid and ask prices or, if more than one in either case, the average of the
average bid and average ask prices) on such date as reported in


                                       25
<PAGE>

the composite transactions for the principal United States securities exchange
on which the Common Stock is traded or, if the Common Stock is not listed on a
United States national or regional securities exchange, as reported by the
National Association of Securities Dealers Automated Quotation System.

      (e) Notice of Election. The Company's notice of election to purchase with
cash or Common Stock or any combination thereof shall be sent to the Holders
(and to beneficial owners as required by applicable law) in the manner provided
in Section 12.02 at the time specified in Section 3.08(c) or (d), as applicable
(the "Company Notice"). Such Company Notice shall state the manner of payment
elected and shall contain the following information:

      In the event the Company has elected to pay the Purchase Price (or a
specified percentage thereof) with Common Stock, the Company Notice shall:

            (i) state that each Holder will receive Common Stock with a Market
      Price determined as of a specified date prior to the Purchase Date equal
      to such specified percentage of the Purchase Price of the Securities held
      by such Holder (except any cash amount to be paid in lieu of fractional
      shares);

            (ii) set forth the method of calculating the Market Price of the
      Common Stock; and

            (iii) state that because the Market Price of Common Stock will be
      determined prior to the Purchase Date, Holders will bear the market risk
      with respect to the value of the Common Stock to be received from the date
      such Market Price is determined to the Purchase Date.

      In any case, each Company Notice shall include a form of Purchase Notice
to be completed by a Securityholder and shall state:

            (i) the Purchase Price and the Conversion Rate;

            (ii) the name and address of the Paying Agent and the Conversion
      Agent;

            (iii) that Securities as to which a Purchase Notice has been given
      may be converted pursuant to Article 11 hereof only if the applicable
      Purchase Notice has been withdrawn in accordance with the terms of this
      Indenture;

            (iv) that Securities must be surrendered to the Paying Agent to
      collect payment of the Purchase Price;

            (v) that the Purchase Price for any Security as to which a Purchase
      Notice has been given and not withdrawn will be paid promptly following
      the later of the Purchase Date and the time of surrender of such Security
      as described in clause (iv) above;

            (vi) the procedures the Holder must follow to exercise rights under
      Section 3.08 and a brief description of those rights;


                                       26
<PAGE>

            (vii) briefly, the conversion rights of the Securities; and

            (viii) the procedures for withdrawing a Purchase Notice (including,
      without limitation, for a conditional withdrawal pursuant to the terms of
      Section 3.08(a)(1)(D) or Section 3.10).

      At the Company's request, the Trustee shall give such Company Notice in
the Company's name and at the Company's expense; provided, however, that, in all
cases, the text of such Company Notice shall be prepared by the Company.

      Upon determination of the actual number of shares of Common Stock to be
issued for each $1,000 Principal Amount at Maturity of Securities, the Company
will publish such determination on the Company's Web site.

      (f) Covenants of the Company. All shares of Common Stock delivered upon
purchase of the Securities shall be newly issued shares or treasury shares,
shall be duly authorized, validly issued, fully paid and nonassessable and shall
be free from preemptive rights and free of any lien or adverse claim.

      The Company shall use its best efforts to list or cause to have quoted any
shares of Common Stock to be issued to purchase Securities on each national
securities exchange or over-the-counter or other domestic market on which the
Common Stock is then listed or quoted.

      (g) Procedure upon Purchase. The Company shall deposit cash (in respect of
a cash purchase under Section 3.08(c) or for fractional interests, as
applicable) or shares of Common Stock, or a combination thereof, as applicable,
at the time and in the manner as provided in Section 3.11, sufficient to pay the
aggregate Purchase Price of all Securities to be purchased pursuant to this
Section 3.08. As soon as practicable after the Purchase Date, the Company shall
deliver to each Holder entitled to receive Common Stock through the Paying
Agent, a certificate for the number of full shares of Common Stock issuable in
payment of the Purchase Price and cash in lieu of any fractional interests. The
person in whose name the certificate for Common Stock is registered shall be
treated as a holder of record of shares of Common Stock on the Business Day
following the Purchase Date. Subject to Section 3.08(d), no payment or
adjustment will be made for dividends on the Common Stock the record date for
which occurred on or prior to the Purchase Date.

      (h) Taxes. If a Holder of a Security is paid in Common Stock, the Company
shall pay any documentary, stamp or similar issue or transfer tax due on such
issue of shares of Common Stock. However, the Holder shall pay any such tax
which is due because the Holder requests the shares of Common Stock to be issued
in a name other than the Holder's name. The Paying Agent may refuse to deliver
the certificates representing the Common Stock being issued in a name other than
the Holder's name until the Paying Agent receives a sum sufficient to pay any
tax which will be due because the shares of Common Stock are to be issued in a
name other than the Holder's name. Nothing herein shall preclude any income tax
withholding required by law or regulations.

      SECTION 3.09. Purchase of Securities at Option of the Holder upon Change
in Control. (a) If on or prior to May 7, 2006 there shall have occurred a Change
in Control, all or


                                       27
<PAGE>

a portion of the Securities of any Holder shall be purchased by the Company, at
the option of the Holder thereof, at the purchase price specified in paragraph 6
of the Securities (the "Change in Control Purchase Price"), as of the date that
is 35 Business Days after the occurrence of the Change in Control (the "Change
in Control Purchase Date"), subject to satisfaction by or on behalf of the
Holder of the requirements set forth in Section 3.09(c).

      A "Change in Control" shall be deemed to have occurred at such time as
either of the following events shall occur:

            (1) There shall be consummated any consolidation or merger of the
      Company pursuant to which the Common Stock would be converted into cash,
      securities or other property, in each case other than a consolidation or
      merger of the Company in which the holders of the Common Stock immediately
      prior to the consolidation or merger have, directly or indirectly, at
      least a majority of the total voting power in the aggregate of all classes
      of capital stock of the continuing or surviving corporation immediately
      after such consolidation or merger; or

            (2) There is a report filed on Schedule 13D or TO (or any successor
      schedule, form or report) pursuant to the Exchange Act, disclosing that
      any person, including such person's Affiliates or Associates (for the
      purposes of this Section 3.09 only, as the term "person" is used in
      Section 13(d)(3) or Section 14(d)(2) of the Exchange Act) has become the
      beneficial owner (as the term "beneficial owner" is defined under Rule
      13d-3 or any successor rule or regulation promulgated under the Exchange
      Act) of 50% or more of the voting power of the Common Stock or other
      Capital Stock into which the Common Stock is reclassified or changed;
      provided, however, that a person shall not be deemed beneficial owner of,
      or to own beneficially, (A) any securities tendered pursuant to a tender
      or exchange offer made by or on behalf of such person or any of such
      person's Affiliates or Associates until such tendered securities are
      accepted for purchase or exchange thereunder, or (B) any securities if
      such beneficial ownership (1) arises solely as a result of a revocable
      proxy delivered in response to a proxy or consent solicitation made
      pursuant to the applicable rules and regulations under the Exchange Act,
      and (2) is not also then reportable on Schedule 13D (or any successor
      schedule) under the Exchange Act.

Notwithstanding the foregoing provisions of this Section 3.09, a Change in
Control shall not be deemed to have occurred by virtue of the Company, any
Subsidiary, any employee stock ownership plan or any other employee benefit plan
of the Company or any Subsidiary, or any person holding Common Stock for or
pursuant to the terms of any such employee benefit plan, filing or becoming
obligated to file a report under or in response to Schedule 13D or Schedule TO
(or any successor schedule, form or report) under the Exchange Act disclosing
beneficial ownership by it of shares of Common Stock, whether in excess of 50%
or otherwise.

      "Associate" shall have the meaning ascribed to such term in Rule 12b-2 of
the General Rules and Regulations under the Exchange Act, as in effect on the
date hereof.

      (b) Within 15 Business Days after the occurrence of a Change in Control,
the Company shall mail a written notice of Change in Control by first-class mail
to the Trustee and to each


                                       28
<PAGE>

Holder (and to beneficial owners as required by applicable law). The notice
shall include a form of Change in Control Purchase Notice to be completed by the
Securityholder and shall state:

            (1) briefly, the events causing a Change in Control and the date of
      such Change in Control;

            (2) the date by which the Change in Control Purchase Notice pursuant
      to this Section 3.09 must be given;

            (3) the Change in Control Purchase Date;

            (4) the Change in Control Purchase Price;

            (5) the name and address of the Paying Agent and the Conversion
      Agent;

            (6) the Conversion Rate and any adjustments thereto;

            (7) that Securities as to which a Change in Control Purchase Notice
      has been given by a Holder may be converted pursuant to Article 11 hereof
      only if the Change in Control Purchase Notice has been withdrawn in
      accordance with the terms of this Indenture;

            (8) that Securities must be surrendered to the Paying Agent to
      collect payment of the Change in Control Purchase Price;

            (9) that the Change in Control Purchase Price for any Security as to
      which a Change in Control Purchase Notice has been duly given and not
      withdrawn will be paid promptly following the later of the Change in
      Control Purchase Date and the time of surrender of such Security as
      described in clause (8) above;

            (10) briefly, the procedures the Holder must follow to exercise
      rights under this Section 3.09;

            (11) briefly, the conversion rights of the Securities; and

            (12) the procedures for withdrawing a Change in Control Purchase
      Notice.

      (c) A Holder may exercise its rights specified in Section 3.09(a) upon
delivery of a written notice of purchase (a "Change in Control Purchase Notice")
to the Paying Agent at any time prior to the close of business on the Change in
Control Purchase Date, stating:

            (1) the certificate number of the Security which the Holder will
      deliver to be purchased;

            (2) the portion of the Principal Amount at Maturity of the Security
      which the Holder will deliver to be purchased, which portion must be
      $1,000 or an integral multiple thereof; and


                                       29
<PAGE>

            (3) that such Security shall be purchased pursuant to the terms and
      conditions specified in paragraph 6 of the Securities.

      The delivery of such Security to the Paying Agent prior to, on or after
the Change in Control Purchase Date (together with all necessary endorsements)
at the offices of the Paying Agent shall be a condition to the receipt by the
Holder of the Change in Control Purchase Price therefor; provided, however, that
such Change in Control Purchase Price shall be so paid pursuant to this Section
3.09 only if the Security so delivered to the Paying Agent shall conform in all
respects to the description thereof set forth in the related Change in Control
Purchase Notice.

      The Company shall purchase from the Holder thereof, pursuant to this
Section 3.09, a portion of a Security if the Principal Amount at Maturity of
such portion is $1,000 or an integral multiple of $1,000. Provisions of this
Indenture that apply to the purchase of all of a Security also apply to the
purchase of such portion of such Security.

      Any purchase by the Company contemplated pursuant to the provisions of
this Section 3.09 shall be consummated by the delivery of the consideration to
be received by the Holder promptly following the later of the Change in Control
Purchase Date and the time of delivery of the Security to the Paying Agent in
accordance with this Section 3.09.

      Notwithstanding anything herein to the contrary, any Holder delivering to
the Paying Agent the Change in Control Purchase Notice contemplated by this
Section 3.09(c) shall have the right to withdraw such Change in Control Purchase
Notice at any time prior to the close of business on the Change in Control
Purchase Date by delivery of a written notice of withdrawal to the Paying Agent
in accordance with Section 3.10.

      The Paying Agent shall promptly notify the Company of the receipt by it of
any Change in Control Purchase Notice or written withdrawal thereof.

      SECTION 3.10. Effect of Purchase Notice or Change in Control Purchase
Notice. Upon receipt by the Paying Agent of the Purchase Notice or Change in
Control Purchase Notice specified in Section 3.08(a) or Section 3.09(c), as
applicable, the Holder of the Security in respect of which such Purchase Notice
or Change in Control Purchase Notice, as the case may be, was given shall
(unless such Purchase Notice or Change in Control Purchase Notice is withdrawn
as specified in the following two paragraphs) thereafter be entitled to receive
solely the Purchase Price or Change in Control Purchase Price, as the case may
be, with respect to such Security. Such Purchase Price or Change in Control
Purchase Price shall be paid to such Holder, subject to receipts of funds and/or
securities by the Paying Agent, promptly following the later of (x) the Purchase
Date or the Change in Control Purchase Date, as the case may be, with respect to
such Security (provided the conditions in Section 3.08(a) or Section 3.09(c), as
applicable, have been satisfied) and (y) the time of delivery of such Security
to the Paying Agent by the Holder thereof in the manner required by Section
3.08(a) or Section 3.09(c), as applicable. Securities in respect of which a
Purchase Notice or Change in Control Purchase Notice, as the case may be, has
been given by the Holder thereof may not be converted pursuant to Article 11
hereof on or after the date of the delivery of such Purchase Notice or Change in
Control Purchase Notice, as the case may be, unless such Purchase Notice or
Change in Control Purchase Notice,


                                       30
<PAGE>

as the case may be, has first been validly withdrawn as specified in the
following two paragraphs.

      A Purchase Notice or Change in Control Purchase Notice, as the case may
be, may be withdrawn by means of a written notice of withdrawal delivered to the
office of the Paying Agent in accordance with the Purchase Notice or Change in
Control Purchase Notice, as the case may be, at any time prior to the close of
business on the Purchase Date or the Change in Control Purchase Date, as the
case may be, specifying:

            (1) the certificate number of the Security in respect of which such
      notice of withdrawal is being submitted,

            (2) the Principal Amount at Maturity of the Security with respect to
      which such notice of withdrawal is being submitted, and

            (3) the Principal Amount at Maturity, if any, of such Security which
      remains subject to the original Purchase Notice or Change in Control
      Purchase Notice, as the case may be, and which has been or will be
      delivered for purchase by the Company.

      A written notice of withdrawal of a Purchase Notice may be in the form set
forth in the preceding paragraph or may be in the form of a conditional
withdrawal contained in a Purchase Notice pursuant to the terms of Section
3.08(a)(1)(D).

      There shall be no purchase of any Securities pursuant to Section 3.08
(other than through the issuance of Common Stock in payment of the Purchase
Price, including cash in lieu of fractional shares) or 3.09 if there has
occurred (prior to, on or after, as the case may be, the giving, by the Holders
of such Securities, of the required Purchase Notice or Change in Control
Purchase Notice, as the case may be) and is continuing an Event of Default
(other than a default in the payment of the Purchase Price or Change in Control
Purchase Price, as the case may be, with respect to such Securities). The Paying
Agent will promptly return to the respective Holders thereof any Securities (x)
with respect to which a Purchase Notice or Change in Control Purchase Notice, as
the case may be, has been withdrawn in compliance with this Indenture, or (y)
held by it during the continuance of an Event of Default (other than a default
in the payment of the Purchase Price or Change in Control Purchase Price, as the
case may be, with respect to such Securities) in which case, upon such return,
the Purchase Notice or Change in Control Purchase Notice with respect thereto
shall be deemed to have been withdrawn.

      SECTION 3.11. Deposit of Purchase Price or Change in Control Purchase
Price. Prior to 10:00 a.m. (New York City time) on the Business Day prior to the
Purchase Date or the Change in Control Purchase Date, as the case may be, the
Company shall deposit with the Trustee or with the Paying Agent (or, if the
Company or a Subsidiary or an Affiliate of either of them is acting as the
Paying Agent, shall segregate and hold in trust as provided in Section 2.04) an
amount of money (in immediately available funds if deposited on such Business
Day) or Common Stock, if permitted hereunder, sufficient to pay the aggregate
Purchase Price or Change in Control Purchase Price, as the case may be, of all
the Securities or portions thereof which are to be purchased as of the Purchase
Date or Change in Control Purchase Date, as the case may be.


                                       31
<PAGE>

      SECTION 3.12. Securities Purchased in Part. Any Security which is to be
purchased only in part shall be surrendered at the office of the Paying Agent
(with, if the Company or the Trustee so requires, due endorsement by, or a
written instrument of transfer in form satisfactory to the Company and the
Trustee duly executed by, the Holder thereof or such Holder's attorney duly
authorized in writing) and the Company shall execute and the Trustee shall
authenticate and deliver to the Holder of such Security, without service charge,
a new Security or Securities, of any authorized denomination as requested by
such Holder in aggregate Principal Amount at Maturity equal to, and in exchange
for, the portion of the Principal Amount at Maturity of the Security so
surrendered which is not purchased.

      SECTION 3.13. Covenant to Comply With Securities Laws Upon Purchase of
Securities. In connection with any offer to purchase or purchase of Securities
under Section 3.08 or 3.09 hereof (provided that such offer or purchase
constitutes an "issuer tender offer" for purposes of Rule 13e-4 (which term, as
used herein, includes any successor provision thereto) under the Exchange Act at
the time of such offer or purchase), the Company shall (i) comply with Rule
13e-4 and Rule 14e-1 and any other tender offer rules under the Exchange Act
which may then be applicable, (ii) file the related Schedule TO (or any
successor schedule, form or report) or any other schedule required under the
Exchange Act, and (iii) otherwise comply with all federal and state securities
laws so as to permit the rights and obligations under Sections 3.08 and 3.09 to
be exercised in the time and in the manner specified in Sections 3.08 and 3.09.

      SECTION 3.14. Repayment to the Company. The Trustee and the Paying Agent
shall return to the Company any cash or shares of Common Stock that remain
unclaimed as provided in paragraph 13 of the Securities, together with interest
or dividends, if any, thereon (subject to the provisions of Section 7.01(f)),
held by them for the payment of the Purchase Price or Change in Control Purchase
Price, as the case may be. To the extent that the aggregate amount of cash or
shares of Common Stock deposited by the Company pursuant to Section 3.11 exceeds
the aggregate Purchase Price or Change in Control Purchase Price, as the case
may be, of the Securities or portions thereof which the Company is obligated to
purchase as of the Purchase Date or Change in Control Purchase Date, as the case
may be, then promptly after the Business Day following the Purchase Date or
Change in Control Purchase Date, as the case may be, the Trustee shall return
any such excess to the Company together with interest or dividends, if any,
thereon (subject to the provisions of Section 7.01(f)).

                                   ARTICLE IV.

                                    COVENANTS

      SECTION 4.01. Payment of Securities. The Company shall promptly make all
payments in respect of the Securities on the dates and in the manner provided in
the Securities or pursuant to this Indenture. Any amounts to be given to the
Trustee or Paying Agent shall be deposited with the Trustee or Paying Agent by
10:00 a.m. New York City time by the Company at the latest on the day such
payment is due. Principal Amount at Maturity, Restated Principal Amount, Issue
Price plus accrued Original Issue Discount, Redemption Price, Purchase Price,
Change in Control Purchase Price and interest, if any, shall be considered paid
on the applicable date due if on such date (or, in the case of a Purchase Price
or Change in Control Purchase Price,


                                       32
<PAGE>

on the Business Day following the applicable Purchase Date or Change in Control
Purchase Date, as the case may be) the Trustee or the Paying Agent holds, in
accordance with this Indenture, money or securities, if permitted hereunder,
sufficient to pay all such amounts then due.

      The Company shall, to the extent permitted by law, pay interest on overdue
amounts at the rate per annum set forth in paragraph 1 of the Securities,
compounded semiannually, which interest shall accrue from the date such overdue
amount was originally due to the date payment of such amount, including interest
thereon, has been made or duly provided for. All such interest shall be payable
on demand. The accrual of such interest on overdue amounts shall be in lieu of,
and not in addition to, the continued accrual of Original Issue Discount.

      SECTION 4.02. SEC and Other Reports. The Company shall file with the
Trustee, within 15 days after it files such annual and quarterly reports,
information, documents and other reports with the SEC, copies of its annual
report and of the information, documents and other reports (or copies of such
portions of any of the foregoing as the SEC may by rules and regulations
prescribe) which the Company is required to file with the SEC pursuant to
Section 13 or 15(d) of the Exchange Act. In the event the Company is at any time
no longer subject to the reporting requirements of Section 13 or 15(d) of the
Exchange Act, it shall continue to provide the Trustee with reports containing
substantially the same information as would have been required to be filed with
the SEC had the Company continued to have been subject to such reporting
requirements. In such event, such reports shall be provided at the times the
Company would have been required to provide reports had it continued to have
been subject to such reporting requirements. The Company also shall comply with
the other provisions of TIA Section 314(a).

      Delivery of such reports, information and documents to the Trustee is for
informational purposes only and the Trustee's receipt of such shall not
constitute constructive notice of any information contained therein or
determinable from information contained therein, including the Company's
compliance with any of its covenants hereunder (as to which the Trustee is
entitled to rely exclusively on Officers' Certificates).

      SECTION 4.03. Compliance Certificate. The Company shall deliver to the
Trustee within 120 days after the end of each fiscal year of the Company
(beginning with the fiscal year ending on December 31, 2001) an Officers'
Certificate, one of the signers of which shall be the principal financial,
principal accounting or principal executive officer of the Company, stating
whether or not to the best knowledge of the signers thereof the Company is in
default in the performance and observance of any of the terms, provisions and
conditions of this Indenture (without regard to any period of grace or
requirement of notice provided hereunder) and if the Company shall be in
default, specifying all such defaults and the nature and status thereof of which
they may have knowledge.

      SECTION 4.04. Further Instruments and Acts. The Company will execute and
deliver such further instruments and do such further acts as may be reasonably
necessary or proper or as the Trustee may request to carry out more effectively
the purposes of this Indenture.


                                       33
<PAGE>

      SECTION 4.05. Maintenance of Office or Agency. The Company will maintain
in the Borough of Manhattan, The City of New York, an office or agency of the
Trustee, Registrar, Paying Agent and Conversion Agent where Securities may be
presented or surrendered for payment, where Securities may be surrendered for
registration of transfer, exchange, purchase, redemption or conversion and where
notices and demands to or upon the Company in respect of the Securities and this
Indenture may be served. The office of the Trustee, at One World Trade Center,
Suite 4711, New York, NY 10048, shall initially be such office or agency for all
of the aforesaid purposes. The Company shall give prompt written notice to the
Trustee of the location, and of any change in the location, of any such office
or agency (other than a change in the location of the office of the Trustee). If
at any time the Company shall fail to maintain any such required office or
agency or shall fail to furnish the Trustee with the address thereof, such
presentations, surrenders, notices and demands may be made or served at the
address of the Trustee set forth in Section 12.02.

      The Company may also from time to time designate one or more other offices
or agencies where the Securities may be presented or surrendered for any or all
such purposes and may from time to time rescind such designations; provided,
however, that no such designation or rescission shall in any manner relieve the
Company of its obligation to maintain an office or agency in the Borough of
Manhattan, The City of New York, for such purposes.

      SECTION 4.06. Delivery of Certain Information. At any time when the
Company is not subject to Section 13 or 15(d) of the Exchange Act, upon the
request of a holder or any beneficial holder of Securities or shares of Common
Stock issued upon conversion thereof, the Company will promptly furnish or cause
to be furnished Rule 144A Information (as defined below) to such Holder or any
beneficial holder of Securities or holder of shares of Common Stock issued upon
conversion of Securities, or to a prospective purchaser of any such security
designated by any such holder, as the case may be, to the extent required to
permit compliance by such Holder or holder with Rule 144A under the Securities
Act in connection with the resale of any such security. "Rule 144A Information"
shall be such information as is specified pursuant to Rule 144A(d)(4) under the
Securities Act.

      SECTION 4.07. Calculation of Original Issue Discount. The Company shall
file with the Trustee promptly at the end of each calendar year (i) a written
notice specifying the amount of original issue discount (including daily rates
and accrual periods) accrued on Outstanding Securities as of the end of such
year and (ii) such other specific information relating to such original issue
discount as may then be relevant under the Internal Revenue Code of 1986, as
amended from time to time.

                                   ARTICLE V.

                              SUCCESSOR CORPORATION

      SECTION 5.01. When Company May Merge or Transfer Assets. The Company shall
not consolidate with or merge with or into any other person or convey, transfer
or lease its properties and assets substantially as an entirety to any person,
unless:


                                       34
<PAGE>

      (a) either (1) the Company shall be the continuing corporation or (2) the
person (if other than the Company) formed by such consolidation or into which
the Company is merged or the person which acquires by conveyance, transfer or
lease the properties and assets of the Company substantially as an entirety (i)
shall be organized and validly existing under the laws of the United States or
any State thereof or the District of Columbia and (ii) shall expressly assume,
by an indenture supplemental hereto, executed and delivered to the Trustee, in
form reasonably satisfactory to the Trustee, all of the obligations of the
Company under the Securities and this Indenture;

      (b) immediately after giving effect to such transaction, no Default or
Event of Default shall have occurred and be continuing; and

      (c) the Company shall have delivered to the Trustee an Officers'
Certificate and an Opinion of Counsel, each stating that such consolidation,
merger, conveyance, transfer or lease and, if a supplemental indenture is
required in connection with such transaction, such supplemental indenture,
comply with this Article 5 and that all conditions precedent herein provided for
relating to such transaction have been satisfied.

      For purposes of the foregoing, the transfer (by lease, assignment, sale or
otherwise) of the properties and assets of one or more Subsidiaries (other than
to the Company or another Subsidiary), which, if such assets were owned by the
Company, would constitute all or substantially all of the properties and assets
of the Company, shall be deemed to be the transfer of all or substantially all
of the properties and assets of the Company.

      The successor person formed by such consolidation or into which the
Company is merged or the successor person to which such conveyance, transfer or
lease is made shall succeed to, and be substituted for, and may exercise every
right and power of, the Company under this Indenture with the same effect as if
such successor had been named as the Company herein; and thereafter, except in
the case of a lease and obligations the Company may have under a supplemental
indenture pursuant to Section 11.14, the Company shall be discharged from all
obligations and covenants under this Indenture and the Securities. Subject to
Section 9.06, the Company, the Trustee and the successor person shall enter into
a supplemental indenture to evidence the succession and substitution of such
successor person and such discharge and release of the Company.

                                   ARTICLE VI.

                              DEFAULTS AND REMEDIES

      SECTION 6.01. Events of Default. An "Event of Default" occurs if:

      (a) after exercise of its option pursuant to Section 10.01 hereof
following a Tax Event, the Company defaults in the payment of interest upon any
Security when such interest becomes due and payable, and such default continues
for a period of 30 days;

      (b) the Company defaults in the payment of the Principal Amount at
Maturity (or, if the Securities have been converted to semiannual coupon notes
following a Tax Event pursuant to


                                       35
<PAGE>

Article 10, the Restated Principal Amount), Issue Price plus accrued Original
Issue Discount, Redemption Price, Purchase Price or Change in Control Purchase
Price on any Security when the same becomes due and payable at its Stated
Maturity, upon redemption, upon declaration, when due for purchase by the
Company or otherwise;

      (c) the Company fails to comply with any of its agreements in the
Securities or this Indenture (other than those referred to in clauses (1) and
(2) above) and such failure continues for 30 days after receipt by the Company
of a Notice of Default;

      (d) default under any Debt, which default results in such Debt becoming or
being declared due and payable prior to the date on which it would otherwise
have become due and payable, and the principal amount of all Debt so
accelerated, together with all Debt due and payable but not paid prior to the
end of any grace period, is $30,000,000 or more, and such acceleration has not
been rescinded or annulled within a period of 30 days after receipt by the
Company of a Notice of Default; provided, however, that if any such default
shall be cured, waived, rescinded or annulled, then the Event of Default by
reason thereof shall be deemed not to have occurred;

      (e) the Company shall fail within 60 days to pay, bond or otherwise
discharge any uninsured judgment or court order in excess of $30,000,000 which
is not stayed;

      (f) the Company pursuant to or under or within the meaning of any
Bankruptcy Law:

            (1) commences a voluntary case or proceeding;

            (2) consents to the entry of an order for relief against it in an
      involuntary case or proceeding or the commencement of any case against it;

            (3) consents to the appointment of a Custodian of it or for any
      substantial part of its property;

            (4) makes a general assignment for the benefit of its creditors;

            (5) files a petition in bankruptcy or answer or consent seeking
      reorganization or relief; or

            (6) consents to the filing of such petition or the appointment of or
      taking possession by a Custodian; or

      (g) a court of competent jurisdiction enters an order or decree under any
Bankruptcy Law that:

            (1) is for relief against the Company in an involuntary case or
      proceeding, or adjudicates the Company insolvent or bankrupt;

            (2) appoints a Custodian of the Company or for any substantial part
      of the property of the Company; or


                                       36
<PAGE>

            (3) orders the winding up or liquidation of the Company;

      and the order or decree remains unstayed and in effect for 60 days.

      Bankruptcy Law" means Title 11, United States Code, or any similar Federal
or state law for the relief of debtors.

      "Custodian" means any receiver, trustee, assignee, liquidator, custodian
or similar official under any Bankruptcy Law.

      A Default under clause (c) or clause (d) above is not an Event of Default
until the Trustee notifies the Company, or the Holders of at least 25% in
aggregate Principal Amount at Maturity of the Securities at the time outstanding
notify the Company and the Trustee, of the Default and the Company does not cure
such Default (and such Default is not waived) within the time specified in
clause (3) or clause (4) above after actual receipt of such notice. Any such
notice must specify the Default, demand that it be remedied and state that such
notice is a "Notice of Default".

      The Company shall deliver to the Trustee, within 30 days after it becomes
aware of the occurrence thereof, written notice of any event which with the
giving of notice or the lapse of time, or both, would become an Event of Default
under clause (3) or clause (4) above, its status and what action the Company is
taking or proposes to take with respect thereto.

      SECTION 6.02. Acceleration. If an Event of Default (other than an Event of
Default specified in Section 6.01(f) or (g)) occurs and is continuing, the
Trustee by notice to the Company, or the Holders of at least 25% in aggregate
Principal Amount at Maturity of the Securities at the time outstanding by notice
to the Company and the Trustee, may declare the Issue Price plus accrued
Original Issue Discount (or, if the Securities have been converted to semiannual
coupon notes following a Tax Event, the Restated Principal Amount, plus accrued
interest) through the date of declaration on all the Securities to be
immediately due and payable. Upon such a declaration, such Issue Price plus
accrued Original Issue Discount shall be due and payable immediately. If an
Event of Default specified in Section 6.01(f) or (g) occurs and is continuing,
the Issue Price plus accrued Original Issue Discount (or, if the Securities have
been converted to semiannual coupon notes following a Tax Event, the Restated
Principal Amount, plus accrued interest) on all the Securities shall become and
be immediately due and payable without any declaration or other act on the part
of the Trustee or any Securityholders. The Holders of a majority in aggregate
Principal Amount at Maturity of the Securities at the time outstanding, by
notice to the Trustee (and without notice to any other Securityholder) may
rescind an acceleration and its consequences if the rescission would not
conflict with any judgment or decree and if all existing Events of Default have
been cured or waived except nonpayment of the Issue Price plus accrued Original
Issue Discount (or, if the Securities have been converted to semiannual coupon
notes following a Tax Event, the Restated Principal Amount, plus accrued
interest) that have become due solely as a result of acceleration and if all
amounts due to the Trustee under Section 7.07 have been paid. No such rescission
shall affect any subsequent Default or impair any right consequent thereto.


                                       37
<PAGE>

      SECTION 6.03. Other Remedies. If an Event of Default occurs and is
continuing, the Trustee may pursue any available remedy to collect the payment
of the Issue Price plus accrued Original Issue Discount (or, if the Securities
have been converted to semiannual coupon notes following a Tax Event, the
Restated Principal Amount, plus accrued interest) on the Securities or to
enforce the performance of any provision of the Securities or this Indenture.

      The Trustee may maintain a proceeding even if the Trustee does not possess
any of the Securities or does not produce any of the Securities in the
proceeding. A delay or omission by the Trustee or any Securityholder in
exercising any right or remedy accruing upon an Event of Default shall not
impair the right or remedy or constitute a waiver of, or acquiescence in, the
Event of Default. No remedy is exclusive of any other remedy. All available
remedies are cumulative.

      SECTION 6.04. Waiver of Past Defaults. The Holders of a majority in
aggregate Principal Amount at Maturity of the Securities at the time
outstanding, by notice to the Trustee (and without notice to any other
Securityholder), may waive an existing Default and its consequences except (1)
an Event of Default described in Section 6.01(a) or (b), (2) a Default in
respect of a provision that under Section 9.02 cannot be amended without the
consent of each Securityholder affected or (3) a Default which constitutes a
failure to convert any Security in accordance with the terms of Article 11. When
a Default is waived, it is deemed cured, but no such waiver shall extend to any
subsequent or other Default or impair any consequent right. This Section 6.04
shall be in lieu of Section 316(a)(1)(B) of the TIA and such Section
316(a)(1)(B) is hereby expressly excluded from this Indenture, as permitted by
the TIA.

      SECTION 6.05. Control by Majority. The Holders of a majority in aggregate
Principal Amount at Maturity of the Securities at the time outstanding may
direct the time, method and place of conducting any proceeding for any remedy
available to the Trustee or of exercising any trust or power conferred on the
Trustee. However, the Trustee may refuse to follow any direction that conflicts
with law or this Indenture or that the Trustee determines in good faith is
unduly prejudicial to the rights of other Securityholders or would involve the
Trustee in personal liability unless the Trustee is offered indemnity
satisfactory to it. This Section 6.05 shall be in lieu of Section 316(a)(1)(A)
of the TIA and such Section 316(a)(1)(A) is hereby expressly excluded from this
Indenture, as permitted by the TIA.

      SECTION 6.06. Limitation on Suits. A Securityholder may not pursue any
remedy with respect to this Indenture or the Securities unless:

      (a) the Holder gives to the Trustee written notice stating that an Event
of Default is continuing;

      (b) the Holders of at least 25% in aggregate Principal Amount at Maturity
of the Securities at the time outstanding make a written request to the Trustee
to pursue the remedy;

      (c) such Holder or Holders offer to the Trustee security or indemnity
satisfactory to the Trustee against any loss, liability or expense; and

      (d) the Trustee does not comply with the request within 60 days after
receipt of such notice, request and offer of security or indemnity and the
Holders of a majority in aggregate


                                       38
<PAGE>

Principal Amount at Maturity of the Securities at the time outstanding do not
give the Trustee a direction inconsistent with the request during such 60-day
period.

      A Securityholder may not use this Indenture to prejudice the rights of any
other Securityholder or to obtain a preference or priority over any other
Securityholder.

      SECTION 6.07. Rights of Holders to Receive Payment. Notwithstanding any
other provision of this Indenture, the right of any Holder to receive payment of
the Principal Amount at Maturity (or if the Securities have been converted to
semiannual coupon notes following a Tax Event pursuant to Article 10, the
Restated Principal Amount), Issue Price plus accrued Original Issue Discount,
Redemption Price, Purchase Price, Change in Control Purchase Price (or, if the
Securities have been converted to semiannual coupon notes following a Tax Event,
the Restated Principal Amount, plus accrued interest) in respect of the
Securities held by such Holder, on or after the respective due dates expressed
in the Securities or any Redemption Date, and to convert the Securities in
accordance with Article 11, or to bring suit for the enforcement of any such
payment on or after such respective dates or the right to convert, shall not be
impaired or affected adversely without the consent of such Holder.

      SECTION 6.08. Collection Suit by Trustee. If an Event of Default described
in Section 6.01(1) or (2) occurs and is continuing, the Trustee may recover
judgment in its own name and as trustee of an express trust against the Company
for the whole amount owing with respect to the Securities and the amounts
provided for in Section 7.07.

      SECTION 6.09. Trustee May File Proofs of Claim. In case of the pendency of
any receivership, insolvency, liquidation, bankruptcy, reorganization,
arrangement, adjustment, composition or other judicial proceeding relative to
the Company or any other obligor upon the Securities or the property of the
Company or of such other obligor or their creditors, the Trustee (irrespective
of whether the Principal Amount at Maturity, Restated Principal Amount, Issue
Price plus accrued Original Issue Discount, Redemption Price, Purchase Price,
Change in Control Purchase Price (or, if the Securities have been converted to
semiannual coupon notes following a Tax Event, the Restated Principal Amount,
plus accrued interest) in respect of the Securities shall then be due and
payable as therein expressed or by declaration or otherwise and irrespective of
whether the Trustee shall have made any demand on the Company for the payment of
any such amount) shall be entitled and empowered, by intervention in such
proceeding or otherwise,

      (a) to file and prove a claim for the whole amount of the Principal Amount
at Maturity, Restated Principal Amount, Issue Price plus accrued Original Issue
Discount, Redemption Price, Purchase Price, Change in Control Purchase Price
(or, if the Securities have been converted to semiannual coupon notes following
a Tax Event, the Restated Principal Amount, plus accrued interest) and to file
such other papers or documents as may be necessary or advisable in order to have
the claims of the Trustee (including any claim for the reasonable compensation,
expenses, disbursements and advances of the Trustee, its agents and counsel or
any other amounts due the Trustee under Section 7.07) and of the Holders allowed
in such judicial proceeding, and

      (b) to collect and receive any moneys or other property payable or
deliverable on any such claims and to distribute the same;


                                       39
<PAGE>

and any custodian, receiver, assignee, trustee, liquidator, sequestrator or
similar official in any such judicial proceeding is hereby authorized by each
Holder to make such payments to the Trustee and, in the event that the Trustee
shall consent to the making of such payments directly to the Holders, to pay the
Trustee any amount due it for the reasonable compensation, expenses,
disbursements and advances of the Trustee, its agents and counsel, and any other
amounts due the Trustee under Section 7.07.

      Nothing herein contained shall be deemed to authorize the Trustee to
authorize or consent to or accept or adopt on behalf of any Holder any plan of
reorganization, arrangement, adjustment or composition affecting the Securities
or the rights of any Holder thereof, or to authorize the Trustee to vote in
respect of the claim of any Holder in any such proceeding.

      SECTION 6.10. Priorities. If the Trustee collects any money pursuant to
this Article 6, it shall pay out the money in the following order:

            FIRST: to the Trustee for amounts due under Section 7.07;

            SECOND: to Securityholders for amounts due and unpaid on the
      Securities for the Principal Amount at Maturity, Restated Principal
      Amount, Issue Price plus accrued Original Issue Discount, Redemption
      Price, Purchase Price, Change in Control Purchase Price (or, if the
      Securities have been converted to semiannual coupon notes following a Tax
      Event, the Restated Principal Amount, plus accrued interest), as the case
      may be, ratably, without preference or priority of any kind, according to
      such amounts due and payable on the Securities; and

            THIRD: the balance, if any, to the Company.

      The Trustee may fix a record date and payment date for any payment to
Securityholders pursuant to this Section 6.10. At least 15 days before such
record date, the Trustee shall mail to each Securityholder and the Company a
notice that states the record date, the payment date and the amount to be paid.

      SECTION 6.11. Undertaking for Costs. In any suit for the enforcement of
any right or remedy under this Indenture or in any suit against the Trustee for
any action taken or omitted by it as Trustee, a court in its discretion may
require the filing by any party litigant (other than the Trustee) in the suit of
an undertaking to pay the costs of the suit, and the court in its discretion may
assess reasonable costs, including reasonable attorneys' fees and expenses,
against any party litigant in the suit, having due regard to the merits and good
faith of the claims or defenses made by the party litigant. This Section 6.11
does not apply to a suit by the Trustee, a suit by a Holder pursuant to Section
6.07 or a suit by Holders of more than 10% in aggregate Principal Amount at
Maturity of the Securities at the time outstanding. This Section 6.11 shall be
in lieu of Section 315(e) of the TIA and such Section 315(e) is hereby expressly
excluded from this Indenture, as permitted by the TIA.

      SECTION 6.12. Waiver of Stay, Extension or Usury Laws. The Company
covenants (to the extent that it may lawfully do so) that it will not at any
time insist upon, or plead, or in any manner whatsoever claim or take the
benefit or advantage of, any stay or extension law or any usury or other law
wherever enacted, now or at any time hereafter in force, which would


                                       40
<PAGE>

prohibit or forgive the Company from paying all or any portion of the Principal
Amount at Maturity, Restated Principal Amount, Issue Price plus accrued Original
Issue Discount, Redemption Price, Purchase Price or Change in Control Purchase
Price in respect of Securities (or, if the Securities have been converted to
semiannual coupon notes following a Tax Event, the Restated Principal Amount,
plus accrued interest), as contemplated herein, or which may affect the
covenants or the performance of this Indenture; and the Company (to the extent
that it may lawfully do so) hereby expressly waives all benefit or advantage of
any such law, and covenants that it will not hinder, delay or impede the
execution of any power herein granted to the Trustee, but will suffer and permit
the execution of every such power as though no such law had been enacted.

                                  ARTICLE VII.

                                     TRUSTEE

      SECTION 7.01. Duties of Trustee. (a) If an Event of Default has occurred
and is continuing, the Trustee shall exercise the rights and powers vested in it
by this Indenture and use the same degree of care and skill in its exercise as a
prudent person would exercise or use under the circumstances in the conduct of
such person's own affairs.

      (b) Except during the continuance of an Event of Default:

            (1) the Trustee need perform only those duties that are specifically
      set forth in this Indenture and no others; and

            (2) in the absence of bad faith on its part, the Trustee may
      conclusively rely, as to the truth of the statements and the correctness
      of the opinions expressed therein, upon certificates or opinions furnished
      to the Trustee and conforming to the requirements of this Indenture.
      However, in case of any such certificates or opinions which by provision
      hereof are specifically required to be furnished to the Trustee, the
      Trustee shall examine the certificates and opinions to determine whether
      or not they conform to the requirements of this Indenture (but need not
      confirm or investigate the accuracy of mathematical calculations or other
      facts stated therein).

This Section 7.01(b) shall be in lieu of Section 3.15(a) of the TIA and such
Section 315(a) is hereby expressly excluded from this Indenture, as permitted by
the TIA.

      (c) The Trustee may not be relieved from liability for its own negligent
action, its own negligent failure to act or its own willful misconduct, except
that:

            (1) this paragraph (c) does not limit the effect of paragraph (b) of
      this Section 7.01;

            (2) the Trustee shall not be liable for any error of judgment made
      in good faith by a Responsible Officer unless it is proved that the
      Trustee was negligent in ascertaining the pertinent facts; and


                                       41
<PAGE>

            (3) the Trustee shall not be liable with respect to any action it
      takes or omits to take in good faith in accordance with a direction
      received by it pursuant to Section 6.05.

Subparagraphs (c)(1), (2) and (3) shall be in lieu of Sections 315(d)(1),
315(d)(2) and 315(d)(3) of the TIA and such Sections 315(d)(1), 315(d)(2) and
315(d)(3) are hereby expressly excluded from this Indenture, as permitted by the
TIA.

      (d) Every provision of this Indenture that in any way relates to the
Trustee is subject to paragraphs (a), (b), (c) and (e) of this Section 7.01.

      (e) The Trustee may refuse to perform any duty or exercise any right or
power or extend or risk its own funds or otherwise incur any financial liability
unless it receives indemnity satisfactory to it against any loss, liability or
expense.

      (f) Money held by the Trustee in trust hereunder need not be segregated
from other funds except to the extent required by law. The Trustee (acting in
any capacity hereunder) shall be under no liability for interest on any money
received by it hereunder unless otherwise agreed in writing with the Company.

      SECTION 7.02. Rights of Trustee. Subject to its duties and
responsibilities under the TIA,

      (a) The Trustee may conclusively rely on any document believed by it to be
genuine and to have been signed or presented by the proper person. The Trustee
need not investigate any fact or matter stated in the document.

      (b) Before the Trustee acts or refrains from acting, it may require an
Officers' Certificate or an Opinion of Counsel. The Trustee shall not be liable
for any action it takes or omits to take in good faith in reliance on such
Officers' Certificate or Opinion of Counsel.

      (c) The Trustee may act through agents and attorneys and shall not be
responsible for the misconduct or negligence of any agent or attorney appointed
with due care.

      (d) Subject to the provisions of Section 7.01(c), the Trustee shall not be
liable for any action it takes or omits to take in good faith which it believes
to be authorized or within its rights or powers.

      (e) The Trustee may consult with counsel selected by it and any advice or
Opinion of Counsel shall be full and complete authorization and protection in
respect of any action taken or suffered or omitted by it hereunder in good faith
and in accordance with such advice or Opinion of Counsel.

      (f) The Trustee shall be under no obligation to exercise any of the rights
or powers vested in it by this Indenture at the request, order or direction of
any of the Holders, pursuant to the provisions of this Indenture, unless such
Holders shall have offered to the Trustee security or indemnity satisfactory to
it against the costs, expenses and liabilities which may be incurred therein or
thereby.


                                       42
<PAGE>

      (g) The Trustee shall not be bound to make any investigation into the
facts or matters stated in any resolution, certificate, statement, instrument,
opinion, report, notice, request, direction, consent, order, bond, debenture,
note, other evidence of indebtedness or other paper or document, but the
Trustee, in its discretion, may make such further inquiry or investigation into
such facts or matters as it may see fit, and, if the Trustee shall determine to
make such further inquiry or investigation, it shall be entitled to examine the
books, records and premises of the Company, personally or by agent or attorney
at the sole cost of the Company and shall incur no liability or additional
liability of any kind by reason of such inquiry or investigation.

      (h) The Trustee shall not be liable for any action taken, suffered, or
omitted to be taken by it in good faith and reasonably believed by it to be
authorized or within the discretion or rights or powers conferred upon it by
this Indenture.

      (i) The Trustee shall not be deemed to have notice of any Default or Event
of Default unless a Responsible Officer of the Trustee has actual knowledge
thereof or unless written notice of any event which is in fact such a default is
received by the Trustee at the Corporate Trust Office of the Trustee, and such
notice references the Securities and this Indenture.

      (j) The rights, privileges, protections, immunities and benefits given to
the Trustee, including, without limitation, its right to be indemnified, are
extended to, and shall be enforceable by, the Trustee in each of its capacities
hereunder, and to each agent, custodian and other Person employed to act
hereunder.

      (k) The Trustee may request that the Company deliver an Officers'
Certificate setting forth the names of individuals and/or titles of officers
authorized at such time to take specified actions pursuant to this Indenture,
which Officers' Certificate may be signed by any person authorized to sign an
Officers' Certificate, including any person specified as so authorized in any
such certificate previously delivered and not superseded.

      SECTION 7.03. Individual Rights of Trustee. The Trustee in its individual
or any other capacity may become the owner or pledgee of Securities and may
otherwise deal with the Company or its Affiliates with the same rights it would
have if it were not Trustee. Any Paying Agent, Registrar, Conversion Agent or
co-registrar may do the same with like rights. However, the Trustee must comply
with Sections 7.10 and 7.11.

      SECTION 7.04. Trustee's Disclaimer. The Trustee makes no representation as
to the validity or adequacy of this Indenture or the Securities, it shall not be
accountable for the Company's use or application of the proceeds from the
Securities, it shall not be responsible for any statement in the registration
statement for the Securities under the Securities Act or in the Indenture or the
Securities (other than its certificate of authentication), or the determination
as to which beneficial owners are entitled to receive any notices hereunder.

      SECTION 7.05. Notice of Defaults. If a Default occurs and if it is known
to the Trustee, the Trustee shall give to each Securityholder notice of the
Default within 90 days after it occurs unless such Default shall have been cured
or waived before the giving of such notice. Except in the case of a Default
described in Section 6.01(a) or (b), the Trustee may withhold the notice if and
so long as a committee of its Responsible Officers in good faith determines that


                                       43
<PAGE>

withholding the notice is in the interests of Securityholders. The second
sentence of this Section 7.05 shall be in lieu of the proviso to Section 315(b)
of the TIA and such proviso is hereby expressly excluded from this Indenture, as
permitted by the TIA.

      SECTION 7.06. Reports by Trustee to Holders. Within 60 days after each May
15 beginning with May 15, 2002, the Trustee shall mail to each Securityholder a
brief report dated as of such May 15 that complies with TIA Section 313(a), if
required by such Section 313(a). The Trustee also shall comply with TIA Section
313(b).

      A copy of each report at the time of its mailing to Securityholders shall
be filed with the SEC and each securities exchange, if any, on which the
Securities are listed. The Company agrees to promptly notify the Trustee
whenever the Securities become listed on any securities exchange and of any
delisting thereof.

      SECTION 7.07. Compensation and Indemnity. The Company agrees:

      (a) to pay to the Trustee from time to time such compensation as the
Company and the Trustee shall from time to time agree in writing for all
services rendered by it hereunder (which compensation shall not be limited (to
the extent permitted by law) by any provision of law in regard to the
compensation of a trustee of an express trust);

      (b) to reimburse the Trustee upon its request for all reasonable expenses,
disbursements and advances incurred or made by the Trustee in accordance with
any provision of this Indenture (including the reasonable compensation and the
expenses, advances and disbursements of its agents and counsel), except any such
expense, disbursement or advance as may be attributable to its negligence or bad
faith; and

      (c) to indemnify the Trustee or any predecessor trustee and their agents
for, and to hold them harmless against, any loss, damage, claim, liability, cost
or expense (including reasonable attorney's fees and expenses and taxes (other
than taxes based upon, measured by or determined by the income of the Trustee))
incurred without negligence or bad faith on its part, arising out of or in
connection with the acceptance or administration of this trust, including the
costs and expenses of defending itself against any claim (whether asserted by
the Company, any Holder or any other Person) or liability in connection with the
exercise or performance of any of its powers or duties hereunder.

      To secure the Company's payment obligations in this Section 7.07, the
Trustee shall have a lien prior to the Securities on all money or property held
or collected by the Trustee, except that held in trust to pay the Principal
Amount at Maturity, Restated Principal Amount, Issue Price plus accrued Original
Issue Discount, Redemption Price, Purchase Price, Change in Control Purchase
Price or interest, if any, as the case may be, on particular Securities.

      The Company's payment obligations pursuant to this Section 7.07 shall
survive the discharge of this Indenture and resignation or removal of the
Trustee. When the Trustee incurs expenses after the occurrence of a Default
specified in Section 6.01(f) or (g), the expenses, including the reasonable fees
and expenses of its counsel, are intended to constitute expenses of
administration under any Bankruptcy Law.


                                       44
<PAGE>

      SECTION 7.08. Replacement of Trustee. The Trustee may resign by so
notifying the Company; provided, however, no such resignation shall be effective
until a successor Trustee has accepted its appointment pursuant to this Section
7.08. The Holders of a majority in aggregate Principal Amount at Maturity of the
Securities at the time outstanding may remove the Trustee by so notifying the
Trustee and the Company. The Company shall remove the Trustee if:

      (a) the Trustee fails to comply with Section 7.10;

      (b) the Trustee is adjudged bankrupt or insolvent;

      (c) a receiver or public officer takes charge of the Trustee or its
property; or

      (d) the Trustee otherwise becomes incapable of acting.

      If the Trustee resigns or is removed or if a vacancy exists in the office
of Trustee for any reason, the Company shall promptly appoint, by resolution of
its Board of Directors, a successor Trustee.

      A successor Trustee shall deliver a written acceptance of its appointment
to the retiring Trustee and to the Company satisfactory in form and substance to
the retiring Trustee and the Company. Thereupon the resignation or removal of
the retiring Trustee shall become effective, and the successor Trustee shall
have all the rights, powers and duties of the Trustee under this Indenture. The
successor Trustee shall mail a notice of its succession to Securityholders. The
retiring Trustee shall promptly transfer all property held by it as Trustee to
the successor Trustee, subject to the lien provided for in Section 7.07.

      If a successor Trustee does not take office within 30 days after the
retiring Trustee resigns or is removed, the retiring Trustee (at the expense of
the Company), the Company or the Holders of a majority in aggregate Principal
Amount at Maturity of the Securities at the time outstanding may petition any
court of competent jurisdiction for the appointment of a successor Trustee.

      If the Trustee fails to comply with Section 7.10, any Securityholder may
petition any court of competent jurisdiction for the removal of the Trustee and
the appointment of a successor Trustee.

      SECTION 7.09. Successor Trustee by Merger. If the Trustee consolidates
with, merges or converts into, or transfers all or substantially all its
corporate trust business or assets to, another corporation, the resulting,
surviving or transferee corporation without any further act shall be the
successor Trustee.

      SECTION 7.10. Eligibility; Disqualification. The Trustee shall at all
times satisfy the requirements of TIA Sections 310(a)(1) and 310(b). The Trustee
shall have a combined capital and surplus of at least $50,000,000 as set forth
in its most recent published annual report of condition. Nothing herein
contained shall prevent the Trustee from filing with the Commission the
application referred to in the penultimate paragraph of TIA Section 310(b).


                                       45
<PAGE>

      SECTION 7.11. Preferential Collection of Claims Against Company. The
Trustee shall comply with TIA Section 311(a), excluding any creditor
relationship listed in TIA Section 311(b). A Trustee who has resigned or been
removed shall be subject to TIA Section 311(a) to the extent indicated therein.

                                  ARTICLE VIII.

                             DISCHARGE OF INDENTURE

      SECTION 8.01. Discharge of Liability on Securities. When (i) the Company
delivers to the Trustee all outstanding Securities (other than Securities
replaced pursuant to Section 2.07) for cancellation or (ii) all outstanding
Securities have become due and payable and the Company deposits with the Trustee
cash or, if expressly permitted by the terms of the Securities or the Indenture,
Common Stock sufficient to pay all amounts due and owing on all outstanding
Securities (other than Securities replaced pursuant to Section 2.07), and if in
either case the Company pays all other sums payable hereunder by the Company,
then this Indenture shall, subject to Section 7.07, cease to be of further
effect. The Trustee shall join in the execution of a document prepared by the
Company acknowledging satisfaction and discharge of this Indenture on demand of
the Company accompanied by an Officers' Certificate and Opinion of Counsel and
at the cost and expense of the Company.

      SECTION 8.02. Repayment to the Company. The Trustee and the Paying Agent
shall return to the Company upon written request any money or securities held by
them for the payment of any amount with respect to the Securities that remains
unclaimed for two years, subject to applicable unclaimed property law. After
return to the Company, Holders entitled to the money or securities must look to
the Company for payment as general creditors unless an applicable abandoned
property law designates another person and the Trustee and the Paying Agent
shall have no further liability to the Securityholders with respect to such
money or securities for that period commencing after the return thereof.

                                   ARTICLE IX.

                                   AMENDMENTS

      SECTION 9.01. Without Consent of Holders. The Company and the Trustee may
amend this Indenture or the Securities without the consent of any
Securityholder:

      (a) to cure any ambiguity, omission, defect or inconsistency; provided,
however that such amendment does not materially adversely affects the rights of
any Securityholder;

      (b) to comply with Article 5 or Section 11.14;

      (c) to provide for uncertificated Securities in addition to certificated
Securities so long as such uncertificated Securities are in registered form for
purposes of the Internal Revenue Code of 1986, as amended;


                                       46
<PAGE>

      (d) to make any change that does not adversely affect the rights of any
Securityholder; or

      (e) to make any change to comply with the TIA, or any amendment thereto,
or to comply with any requirement of the SEC in connection with the
qualification of the Indenture under the TIA.

      SECTION 9.02. With Consent of Holders. With the written consent of the
Holders of at least a majority in aggregate Principal Amount at Maturity of the
Securities at the time outstanding, the Company and the Trustee may amend this
Indenture or the Securities. However, without the consent of each Securityholder
affected, an amendment to this Indenture or the Securities may not:

      (a) make any change to the Principal Amount at Maturity of Securities
whose Holders must consent to an amendment;

      (b) make any change in the manner or rate of accrual in connection with
Original Issue Discount, reduce the rate of interest referred to in paragraph 1
of the Securities, reduce the rate of interest referred to in Section 10.01 upon
the occurrence of a Tax Event, or extend the time for payment of Original Issue
Discount or interest, if any, on any Security;

      (c) reduce the Principal Amount at Maturity, Restated Principal Amount or
the Issue Price of or extend the Stated Maturity of any Security;

      (d) reduce the Redemption Price, Purchase Price or Change in Control
Purchase Price of any Security;

      (e) make any Security payable in currency other than that stated in the
Security;

      (f) make any change in Section 6.04, Section 6.07 or this Section 9.02,
except to increase any percentage set forth therein;

      (g) make any change that adversely affects the right to convert any
Security; or

      (h) make any change that adversely affects the right to require the
Company to purchase the Securities in accordance with the terms thereof and this
Indenture.

      It shall not be necessary for the consent of the Holders under this
Section 9.02 to approve the particular form of any proposed amendment, but it
shall be sufficient if such consent approves the substance thereof.

      After an amendment under this Section 9.02 becomes effective, the Company
shall mail to each Holder a notice briefly describing the amendment.

      SECTION 9.03. Compliance with Trust Indenture Act. Every supplemental
indenture executed pursuant to this Article shall comply with the TIA.

      SECTION 9.04. Revocation and Effect of Consents, Waivers and Actions.
Until an amendment, waiver or other action by Holders becomes effective, a
consent thereto by a Holder


                                       47
<PAGE>

of a Security hereunder is a continuing consent by the Holder and every
subsequent Holder of that Security or portion of the Security that evidences the
same obligation as the consenting Holder's Security, even if notation of the
consent, waiver or action is not made on the Security. However, any such Holder
or subsequent Holder may revoke the consent, waiver or action as to such
Holder's Security or portion of the Security if the Trustee receives the notice
of revocation before the date the amendment, waiver or action becomes effective.
After an amendment, waiver or action becomes effective, it shall bind every
Securityholder.

      SECTION 9.05. Notation on or Exchange of Securities. Securities
authenticated and delivered after the execution of any supplemental indenture
pursuant to this Article may, and shall if required by the Trustee, bear a
notation in form approved by the Trustee as to any matter provided for in such
supplemental indenture. If the Company shall so determine, new Securities so
modified as to conform, in the opinion of the Trustee and the Board of
Directors, to any such supplemental indenture may be prepared and executed by
the Company and authenticated and delivered by the Trustee in exchange for
outstanding Securities.

      SECTION 9.06. Trustee to Sign Supplemental Indentures. The Trustee shall
sign any supplemental indenture authorized pursuant to this Article 9 if the
amendment contained therein does not adversely affect the rights, duties,
liabilities or immunities of the Trustee. If it does, the Trustee may, but need
not, sign such supplemental indenture. In signing such supplemental indenture
the Trustee shall be entitled to receive, and (subject to the provisions of
Section 7.01) shall be fully protected in relying upon, an Officers' Certificate
and an Opinion of Counsel stating that such amendment is authorized or permitted
by this Indenture.

      SECTION 9.07. Effect of Supplemental Indentures. Upon the execution of any
supplemental indenture under this Article, this Indenture shall be modified in
accordance therewith, and such supplemental indenture shall form a part of this
Indenture for all purposes; and every Holder of Securities theretofore or
thereafter authenticated and delivered hereunder shall be bound thereby.

                                   ARTICLE X.

                          SPECIAL TAX EVENT CONVERSION

      SECTION 10.01. Optional Conversion to Semiannual Coupon Note Upon Tax
Event. From and after (i) the date (the "Tax Event Date") of the occurrence of a
Tax Event and (ii) the date the Company exercises such option, whichever is
later (the "Option Exercise Date"), at the option of the Company, interest in
lieu of future Original Issue Discount shall accrue at the rate of 0.5% per
annum on a Restated Principal Amount per $1,000 original Principal Amount at
Maturity (the "Restated Principal Amount") equal to the Issue Price plus
Original Issue Discount accrued through the Option Exercise Date and shall be
payable semiannually on May 7 and November 7 of each year (each an "Interest
Payment Date") to Holders of record at the close of business on April 21 or
October 22 (each a "Regular Record Date") immediately preceding such Interest
Payment Date. Interest will be computed on the basis of a 360-day year comprised
of twelve 30- day months and will accrue from the most recent date on which
interest has been paid or, if no interest has been paid, from the Option
Exercise Date. Within 15 days of the occurrence


                                       48
<PAGE>

of a Tax Event, the Company shall mail a written notice of such Tax Event by
first-class mail to the Trustee and within 15 days of its exercise of such
option the Company shall mail a written notice of the Option Exercise Date by
first-class mail to the Trustee and Holders of the Securities. From and after
the Option Exercise Date, (i) the Company shall be obligated to pay at Stated
Maturity, in lieu of the Principal Amount at Maturity of a Security, the
Restated Principal Amount thereof and (ii) "Issue Price and accrued Original
Issue Discount," "Issue Price plus Original Issue Discount" or similar words, as
used herein, shall mean Restated Principal Amount plus accrued and unpaid
interest with respect to any Security. Securities authenticated and delivered
after the Option Exercise Date may, and shall if required by the Trustee, bear a
notation in a form approved by the Trustee as to the conversion of the
Securities to semiannual coupon notes.

      SECTION 10.02. Payment of Interest; Interest Rights Preserved. (a)
Interest on any Security that is payable, and is punctually paid or duly
provided for, on any Interest Payment Date shall be paid to the person in whose
name that Security is registered at the close of business on the Regular Record
Date for such interest at the office or agency of the Company maintained for
such purpose. Each installment of interest on any Security shall be paid by
check; provided that payment by wire transfer of immediately available funds
will be required with respect to principal on and interest, if any, on all
Global Securities and all other Securities the holders of which shall have
provided wire transfer instructions to the Company or the Paying Agent for an
account maintained by the payee located inside the United States. In the case of
a permanent Global Security, interest payable on any Interest Payment Date will
be paid to the Depositary, with respect to that portion of such permanent Global
Security held for its account by Cede & Co. for the purpose of permitting such
party to credit the interest received by it in respect of such permanent Global
Security to the accounts of the beneficial owners thereof.

      (b) Except as otherwise specified with respect to the Securities, any
interest on any Security that is payable on any Interest Payment Date, but is
not punctually paid or duly provided for, within 30 days following on any
Interest Payment Date (herein called "Defaulted Interest", which term shall
include any accrued and unpaid interest that has accrued on such defaulted
amount in accordance with paragraph 1 of the Securities), shall forthwith cease
to be payable to the registered Holder thereof on the relevant Regular Record
Date by virtue of having been such Holder, and such Defaulted Interest may be
paid by the Company, as its election in each case, as provided in clause (1) or
(2) below:

            (1) The Company may elect to make payment of any Defaulted Interest
      to the persons in whose names the Securities are registered at the close
      of business on a Special Record Date for the payment of such Defaulted
      Interest, which shall be fixed in the following manner. The Company shall
      notify the Trustee in writing of the amount of Defaulted Interest proposed
      to be paid on each Security and the date of the proposed payment (which
      shall not be less than 20 days after such notice is received by the
      Trustee), and at the same time the Company shall deposit with the Trustee
      an amount of money equal to the aggregate amount proposed to be paid in
      respect of such Defaulted Interest or shall make arrangements satisfactory
      to the Trustee for such deposit on or prior to the date of the proposed
      payment, such money when deposited to be held in trust for the benefit of
      the persons entitled to such Defaulted Interest as in this clause
      provided. Thereupon the Trustee shall fix a Special Record Date for the
      payment of such Defaulted


                                       49
<PAGE>

      Interest which shall be not more than 15 days and not less than 10 days
      prior to the date of the proposed payment and not less than 10 days after
      the receipt by the Trustee of the notice of the proposed payment. The
      Trustee shall promptly notify the Company of such Special Record Date and,
      in the name and at the expense of the Company, shall cause notice of the
      proposed payment of such Defaulted Interest and the Special Record Date
      therefor to be mailed, first-class postage prepaid, to each Holder of
      Securities at his address as it appears on the list of Securityholders
      maintained pursuant to Section 2.05 not less than 10 days prior to such
      Special Record Date. Notice of the proposed payment of such Defaulted
      Interest and the Special Record Date therefor having been mailed as
      aforesaid, such Defaulted Interest shall be paid to the persons in whose
      names the Securities are registered at the close of business on such
      Special Record Date and shall no longer be payable pursuant to the
      following clause (2).

            (2) The Company may make payment of any Defaulted Interest on the
      Securities in any other lawful manner not inconsistent with the
      requirements of any securities exchange on which such Securities may be
      listed, and upon such notice as may be required by such exchange, if,
      after notice given by the Company to the Trustee of the proposed payment
      pursuant to this clause, such manner of payment shall be deemed
      practicable by the Trustee.

      Subject to the foregoing provisions of this Section and Section 2.06, each
Security delivered under this Indenture upon registration of transfer of or in
exchange for or in lieu of any other Security shall carry the rights to interest
accrued and unpaid, and to accrue, which were carried by such other Security.

                                   ARTICLE XI.

                                   CONVERSION

      SECTION 11.01. Conversion Privilege. A Holder of a Security may convert
such Security into Common Stock at any time during the period stated in
paragraph 8 of the Securities. The number of shares of Common Stock issuable
upon conversion of a Security per $1,000 of Principal Amount at Maturity thereof
(the "Conversion Rate") shall be that set forth in paragraph 8 of the
Securities, subject to adjustment as herein set forth.

      A Holder may convert a portion of the Principal Amount at Maturity of a
Security if the portion is $1,000 or an integral multiple of $1,000. Provisions
of this Indenture that apply to conversion of all of a Security also apply to
conversion of a portion of a Security.

      "Average Sale Price" means the average of the Sale Prices of the Common
Stock for the shorter of

            (1) 30 consecutive trading days ending on the last full trading day
      prior to the Time of Determination with respect to the rights, warrants or
      options or distribution in respect of which the Average Sale Price is
      being calculated, or


                                       50
<PAGE>

            (2) the period (x) commencing on the date next succeeding the first
      public announcement of (a) the issuance of rights, warrants or options or
      (b) the distribution, in each case, in respect of which the Average Sale
      Price is being calculated and (y) proceeding through the last full trading
      day prior to the Time of Determination with respect to the rights,
      warrants or options or distribution in respect of which the Average Sale
      Price is being calculated (excluding days within such period, if any,
      which are not trading days), or

            (3) the period, if any, (x) commencing on the date next succeeding
      the Ex-Dividend Time with respect to the next preceding (a) issuance of
      rights, warrants or options or (b) distribution, in each case, for which
      an adjustment is required by the provisions of Section 11.06(d), 11.07 or
      11.08 and (y) proceeding through the last full trading day prior to the
      Time of Determination with respect to the rights, warrants or options or
      distribution in respect of which the Average Sale Price is being
      calculated (excluding days within such period, if any, which are not
      trading days).

      In the event that the Ex-Dividend Time (or in the case of a subdivision,
combination or reclassification, the effective date with respect thereto) with
respect to a dividend, subdivision, combination or reclassification to which
Section 11.06(1), (2), (3) or (5) applies occurs during the period applicable
for calculating "Average Sale Price" pursuant to the definition in the preceding
sentence, "Average Sale Price" shall be calculated for such period in a manner
determined by the Board of Directors to reflect the impact of such dividend,
subdivision, combination or reclassification on the Sale Price of the Common
Stock during such period.

      "Time of Determination" means the time and date of the earlier of (i) the
determination of stockholders entitled to receive rights, warrants or options or
a distribution, in each case, to which Section 11.07 or 11.08 applies and (ii)
the time ("Ex-Dividend Time") immediately prior to the commencement of
"ex-dividend" trading for such rights, warrants or options or distribution on
the New York Stock Exchange or such other principal national or regional
exchange or market on which the Common Stock is then listed or quoted.

      SECTION 11.02. Conversion Procedure. To convert a Security a Holder must
satisfy the requirements in paragraph 8 of the Securities. The date on which the
Holder satisfies all those requirements is the conversion date (the "Conversion
Date"). As soon as practicable after the Conversion Date, the Company shall
deliver to the Holder, through the Conversion Agent, a certificate for the
number of full shares of Common Stock issuable upon the conversion and cash in
lieu of any fractional share determined pursuant to Section 11.03. The person in
whose name the certificate is registered shall be treated as a stockholder of
record on and after the Conversion Date; provided, however, that no surrender of
a Security on any date when the stock transfer books of the Company shall be
closed shall be effective to constitute the person or persons entitled to
receive the shares of Common Stock upon such conversion as the record holder or
holders of such shares of Common Stock on such date, but such surrender shall be
effective to constitute the person or persons entitled to receive such shares of
Common Stock as the record holder or holders thereof for all purposes at the
close of business on the next succeeding day on which such stock transfer books
are open; such conversion shall be at the Conversion Rate in effect on the date
that such Security shall have been surrendered for conversion, as if the stock


                                       51
<PAGE>

transfer books of the Company had not been closed. Upon conversion of a
Security, such person shall no longer be a Holder of such Security.

      No payment or adjustment will be made for dividends on, or other
distributions with respect to, any Common Stock except as provided in this
Article 11. On conversion of a Security, that portion of accrued Original Issue
Discount (or interest, if the Company has exercised its option provided for in
Section 10.01) attributable to the period from the Issue Date (or, if the
Company has exercised the option provided for in Section 10.01, the later of (x)
the date of such exercise and (y) the date on which interest was last paid) of
the Security through the Conversion Date with respect to the converted Security
shall not be canceled, extinguished or forfeited, but rather shall be deemed to
be paid in full to the Holder thereof through delivery of the Common Stock
(together with the cash payment, if any, in lieu of fractional shares) in
exchange for the Security being converted pursuant to the provisions hereof; and
the fair market value of such shares of Common Stock (together with any such
cash payment in lieu of fractional shares) shall be treated as issued, to the
extent thereof, first in exchange for Original Issue Discount (or interest, if
the Company has exercised its option provided for in Section 10.01) accrued
through the Conversion Date, and the balance, if any, of such fair market value
of such Common Stock (and any such cash payment) shall be treated as issued in
exchange for the Issue Price of the Security being converted pursuant to the
provisions hereof.

      If the Holder converts more than one Security at the same time, the number
of shares of Common Stock issuable upon the conversion shall be based on the
total Principal Amount at Maturity of the Securities converted.

      If the last day on which a Security may be converted is a Legal Holiday,
the Security may be surrendered on the next succeeding day that is not a Legal
Holiday.

      Upon surrender of a Security that is converted in part, the Company shall
execute, and the Trustee shall authenticate and deliver to the Holder, a new
Security in an authorized denomination equal in Principal Amount at Maturity to
the unconverted portion of the Security surrendered.

      SECTION 11.03. Fractional Shares. The Company will not issue a fractional
share of Common Stock upon conversion of a Security. Instead, the Company will
deliver cash for the current market value of the fractional share. The current
market value of a fractional share shall be determined, to the nearest 1/1,000th
of a share, by multiplying the Sale Price, on the last trading day prior to the
Conversion Date, of a full share by the fractional amount and rounding the
product to the nearest whole cent.

      SECTION 11.04. Taxes on Conversion. If a Holder converts a Security, the
Company shall pay any documentary, stamp or similar issue or transfer tax due on
the issue of shares of Common Stock upon the conversion. However, the Holder
shall pay any such tax which is due because the Holder requests the shares to be
issued in a name other than the Holder's name. The Conversion Agent may refuse
to deliver the certificates representing the Common Stock being issued in a name
other than the Holder's name until the Conversion Agent receives a sum
sufficient to pay any tax which will be due because the shares are to be issued
in a name other


                                       52
<PAGE>

than the Holder's name. Nothing herein shall preclude any tax withholding
required by law or regulations.

      SECTION 11.05. Company to Provide Stock. The Company shall, prior to
issuance of any Securities under this Article 11, and from time to time as may
be necessary, reserve out of its authorized but unissued Common Stock a
sufficient number of shares of Common Stock to permit the conversion of the
Securities.

      All shares of Common Stock delivered upon conversion of the Securities
shall be newly issued shares or treasury shares, shall be duly and validly
issued and fully paid and nonassessable and shall be free from preemptive rights
and free of any lien or adverse claim.

      The Company will endeavor promptly to comply with all Federal and state
securities laws regulating the offer and delivery of shares of Common Stock upon
conversion of Securities, if any, and will list or cause to have quoted such
shares of Common Stock on each national securities exchange or in the
over-the-counter market or such other market on which the Common Stock is then
listed or quoted.

      SECTION 11.06. Adjustment for Change in Capital Stock. If, after the Issue
Date of the Securities, the Company:

      (a) pays a dividend or makes a distribution on its Common Stock in shares
of its Common Stock or other Capital Stock;

      (b) subdivides its outstanding shares of Common Stock into a greater
number of shares;

      (c) combines its outstanding shares of Common Stock into a smaller number
of shares;

      (d) pays a dividend or makes a distribution on its Common Stock in shares
of its Capital Stock (other than Common Stock or rights, warrants or options for
its Capital Stock); or

      (e) issues by reclassification of its Common Stock any shares of its
Capital Stock (other than rights, warrants or options for its Capital Stock),

      then the conversion privilege and the Conversion Rate in effect
immediately prior to such action shall be adjusted so that the Holder of a
Security thereafter converted may receive the number of shares of Capital Stock
of the Company which such Holder would have owned immediately following such
action if such Holder had converted the Security immediately prior to such
action.

      The adjustment shall become effective immediately after the record date in
the case of a dividend or distribution and immediately after the effective date
in the case of a subdivision, combination or reclassification.

      If after an adjustment a Holder of a Security upon conversion of such
Security may receive shares of two or more classes of Capital Stock of the
Company, the Conversion Rate shall thereafter be subject to adjustment upon the
occurrence of an action taken with respect to


                                       53
<PAGE>

any such class of Capital Stock as is contemplated by this Article 11 with
respect to the Common Stock, on terms comparable to those applicable to Common
Stock in this Article 11.

      SECTION 11.07. Adjustment for Rights Issue. If after the Issue Date of the
Securities, the Company distributes any rights, warrants or options to all
holders of its Common Stock entitling them, for a period expiring within 60 days
after the record date for such distribution, to purchase shares of Common Stock
at a price per share less than the Sale Price as of the Time of Determination,
the Conversion Rate shall be adjusted in accordance with the formula:

                                (O + N)
               R'  =  R x ------------------
                            (O + (N x P)/M)

      where:

      R'= the adjusted Conversion Rate.

      R = the current Conversion Rate.

      O = the number of shares of Common Stock outstanding on the record date
          for the distribution to which this Section 11.07 is being applied.

      N = the number of additional shares of Common Stock offered pursuant to
          the distribution.

      P = the offering price per share of the additional shares.

      M = the Average Sale Price, minus, in the case of (i) a distribution to
          which Section 11.06(d) applies or (ii) a distribution to which Section
          11.08 applies, for which, in each case, (x) the record date shall
          occur on or before the record date for the distribution to which this
          Section 11.07 applies and (y) the Ex-Dividend Time shall occur on or
          after the date of the Time of Determination for the distribution to
          which this Section 11.07 applies, the fair market value (on the record
          date for the distribution to which this Section 11.07 applies) of the

          (1) Capital Stock of the Company distributed in respect of each share
          of Common Stock in such Section 11.06(d) distribution and

          (2) assets of the Company or debt securities or any rights, warrants
          or options to purchase securities of the Company distributed in
          respect of each share of Common Stock in such Section 11.08
          distribution.

      The Board of Directors shall determine fair market values for the purposes
      of this Section 11.07.

      The adjustment shall become effective immediately after the record date
for the determination of shareholders entitled to receive the rights, warrants
or options to which this Section 11.07 applies. If all of the shares of Common
Stock subject to such rights, warrants or options have not been issued when such
rights, warrants or options expire, then the Conversion


                                       54
<PAGE>

Rate shall promptly be readjusted to the Conversion Rate which would then be in
effect had the adjustment upon the issuance of such rights, warrants or options
been made on the basis of the actual number of shares of Common Stock issued
upon the exercise of such rights, warrants or options.

      No adjustment shall be made under this Section 11.07 if the application of
the formula stated above in this Section 11.07 would result in a value of R'
that is equal to or less than the value of R.

      SECTION 11.08. Adjustment for Other Distributions. If, after the Issue
Date of the Securities, the Company distributes to all holders of its Common
Stock any of its assets, or debt securities or any rights, warrants or options
to purchase securities of the Company (including securities or cash, but
excluding (x) distributions of Capital Stock referred to in Section 11.06 and
distributions of rights, warrants or options referred to in Section 11.07 and
(y) cash dividends or other cash distributions that are paid out of consolidated
current net earnings or earnings retained in the business as shown on the books
of the Company unless such cash dividends or other cash distributions are
Extraordinary Cash Dividends) the Conversion Rate shall be adjusted, subject to
the provisions of the last paragraph of this Section 11.08, in accordance with
the formula:

                                M
                 R'  =  R x ----------
                               M-F

      where:

      R'=  the adjusted Conversion Rate.

      R =  the current Conversion Rate.

      M =  the Average Sale Price, minus, in the case of a distribution to
           which Section 11.06(d) applies, for which (i) the record date shall
           occur on or before the record date for the distribution to which this
           Section 11.08 applies and (ii) the Ex-Dividend Time shall occur on or
           after the date of the Time of Determination for the distribution to
           which this Section 11.08 applies, the fair market value (on the
           record date for the distribution to which this Section 11.08 applies)
           of any Capital Stock of the Company distributed in respect of each
           share of Common Stock in such Section 11.06(d) distribution.

      F =  the fair market value (on the record date for the distribution to
           which this Section 11.08 applies) of the assets, securities, rights,
           warrants or options to be distributed in respect of each share of
           Common Stock in the distribution to which this Section 11.08 is being
           applied (including, in the case of cash dividends or other cash
           distributions giving rise to an adjustment, all such cash distributed
           concurrently).

      The Board of Directors shall determine fair market values for the purposes
      of this Section 11.08.


                                       55
<PAGE>

      The adjustment shall become effective immediately after the record date
for the determination of shareholders entitled to receive the distribution to
which this Section 11.08 applies.

      For purposes of this Section 11.08, the term "Extraordinary Cash Dividend"
shall mean any cash dividend with respect to the Common Stock the amount of
which, together with the aggregate amount of cash dividends on the Common Stock
to be aggregated with such cash dividend in accordance with the provisions of
this paragraph, equals or exceeds the threshold percentages set forth in item
(i) below. For purposes of item (i) below, the "Measurement Period" with respect
to a cash dividend on the Common Stock shall mean the 365 consecutive day period
ending on the date prior to the Ex-Dividend Time with respect to such cash
dividend, and the "Relevant Cash Dividends" with respect to a cash dividend on
the Common Stock shall mean the cash dividends on the Common Stock with
Ex-Dividend Times occurring in the Measurement Period.

            (i) If, upon the date prior to the Ex-Dividend Time with respect to
      a cash dividend on the Common Stock, the aggregate amount of such cash
      dividend together with the amounts of all Relevant Cash Dividends equals
      or exceeds on a per share basis 5% of the Sale Price of the Common Stock
      on the last trading day preceding the date of declaration by the Board of
      Directors of the cash dividend with respect to which this provision is
      being applied, then such cash dividend together with all Relevant Cash
      Dividends, shall be deemed to be an Extraordinary Cash Dividend and for
      purposes of applying the formula set forth above in this Section 11.08,
      the value of "F" shall be equal to (y) the aggregate amount of such cash
      dividend together with the amount of all Relevant Cash Dividends, minus
      (z) the aggregate amount of all Relevant Cash Dividends for which a prior
      adjustment in the Conversion Rate was previously made under this Section
      11.08.

            In making the determinations required by item (i) above, the amount
      of cash dividends paid on a per share basis and the amount of any Relevant
      Cash Dividends specified in item (i) above shall be appropriately adjusted
      to reflect the occurrence during such period of any event described in
      Section 11.06.

      SECTION 11.09. When Adjustment May Be Deferred. No adjustment in the
Conversion Rate need be made unless the adjustment would require an increase or
decrease of at least 1% in the Conversion Rate. Any adjustments that are not
made shall be carried forward and taken into account in any subsequent
adjustment.

      All calculations under this Article 11 shall be made to the nearest cent
or to the nearest 1/1,000th of a share, as the case may be.

      SECTION 11.10. When No Adjustment Required. No adjustment need be made for
a transaction referred to in Section 11.06, 11.07, 11.08 or 11.14 if
Securityholders are to participate in the transaction on a basis and with notice
that the Board of Directors determines to be fair and appropriate in light of
the basis and notice on which holders of Common Stock participate in the
transaction. Such participation by Securityholders may include participation


                                       56
<PAGE>

upon conversion provided that an adjustment shall be made at such time as the
Securityholders are no longer entitled to participate.

      No adjustment need be made for rights to purchase Common Stock pursuant to
a Company plan for reinvestment of dividends or interest.

      No adjustment need be made for a change in the par value or no par value
of the Common Stock.

      To the extent the Securities become convertible pursuant to this Article
11 into cash, no adjustment need be made thereafter as to the cash. Interest
will not accrue on the cash.

      SECTION 11.11. Notice of Adjustment. Whenever the Conversion Rate is
adjusted, the Company shall promptly mail to Securityholders a notice of the
adjustment. The Company shall file with the Trustee and the Conversion Agent
such notice and a certificate from the Company's independent public accountants
briefly stating the facts requiring the adjustment and the manner of computing
it. The certificate shall be conclusive evidence that the adjustment is correct.
Neither the Trustee nor any Conversion Agent shall be under any duty or
responsibility with respect to any such certificate except to exhibit the same
to any Holder desiring inspection thereof.

      SECTION 11.12. Voluntary Increase. The Company from time to time may
increase the Conversion Rate by any amount for any period of time. Whenever the
Conversion Rate is increased, the Company shall mail to Securityholders and file
with the Trustee and the Conversion Agent a notice of the increase. The Company
shall mail the notice at least 15 days before the date the increased Conversion
Rate takes effect. The notice shall state the increased Conversion Rate and the
period it will be in effect.

      A voluntary increase of the Conversion Rate does not change or adjust the
Conversion Rate otherwise in effect for purposes of Section 11.06, 11.07 or
11.08.

      SECTION 11.13. Notice of Certain Transactions. If:

      (a) the Company takes any action that would require an adjustment in the
Conversion Rate pursuant to Section 11.06, 11.07 or 11.08 (unless no adjustment
is to occur pursuant to Section 11.10); or

      (b) the Company takes any action that would require a supplemental
indenture pursuant to Section 11.14; or

      (c) there is a liquidation or dissolution of the Company;

then the Company shall mail to Securityholders and file with the Trustee and the
Conversion Agent a notice stating the proposed record date for a dividend or
distribution or the proposed effective date of a subdivision, combination,
reclassification, consolidation, merger, binding share exchange, transfer,
liquidation or dissolution. The Company shall file and mail the notice at least
15 days before such date. Failure to file or mail the notice or any defect in it
shall not affect the validity of the transaction.


                                       57
<PAGE>

      SECTION 11.14. Reorganization of Company; Special Distributions. If the
Company is a party to a transaction subject to Section 5.01 (other than a sale
of all or substantially all of the assets of the Company in a transaction in
which the holders of Common Stock immediately prior to such transaction do not
receive securities, cash or other assets of the Company or any other person) or
a merger or binding share exchange which reclassifies or changes its outstanding
Common Stock, the person obligated to deliver securities, cash or other assets
upon conversion of Securities shall enter into a supplemental indenture. If the
issuer of securities deliverable upon conversion of Securities is an Affiliate
of the successor Company, that issuer shall join in the supplemental indenture.

      The supplemental indenture shall provide that the Holder of a Security may
convert it into the kind and amount of securities, cash or other assets which
such Holder would have received immediately after the consolidation, merger,
binding share exchange or transfer if such Holder had converted the Security
immediately before the effective date of the transaction, assuming (to the
extent applicable) that such Holder (i) was not a constituent person or an
Affiliate of a constituent person to such transaction; (ii) made no election
with respect thereto; and (iii) was treated alike with the plurality of
non-electing Holders. The supplemental indenture shall provide for adjustments
which shall be as nearly equivalent as may be practical to the adjustments
provided for in this Article 11. The successor Company shall mail to
Securityholders a notice briefly describing the supplemental indenture.

      If this Section applies, neither Section 11.06 nor 11.07 applies.

      If the Company makes a distribution to all holders of its Common Stock of
any of its assets, or debt securities or any rights, warrants or options to
purchase securities of the Company that, but for the provisions of Section 11.08
(c), would otherwise result in an adjustment in the Conversion Rate pursuant to
the provisions of Section 11.08, then, from and after the record date for
determining the holders of Common Stock entitled to receive the distribution, a
Holder of a Security that converts such Security in accordance with the
provisions of this Indenture shall upon such conversion be entitled to receive,
in addition to the shares of Common Stock into which the Security is
convertible, the kind and amount of securities, cash or other assets comprising
the distribution that such Holder would have received if such Holder had
converted the Security immediately prior to the record date for determining the
holders of Common Stock entitled to receive the distribution.

      SECTION 11.15. Company Determination Final. Any determination that the
Company or the Board of Directors must make pursuant to Section 11.03, 11.06,
11.07, 11.08, 11.09, 11.10, 11.14 or 11.17 is conclusive.

      SECTION 11.16. Trustee's Adjustment Disclaimer. The Trustee has no duty to
determine when an adjustment under this Article 11 should be made, how it should
be made or what it should be. The Trustee has no duty to determine whether a
supplemental indenture under Section 11.14 need be entered into or whether any
provisions of any supplemental indenture are correct. The Trustee shall not be
accountable for and makes no representation as to the validity or value of any
securities or assets issued upon conversion of Securities. The Trustee shall not
be responsible for the Company's failure to comply with this Article 11. Each
Conversion Agent shall have the same protection under this Section 11.16 as the
Trustee.


                                       58
<PAGE>

      SECTION 11.17. Simultaneous Adjustments. In the event that this Article 11
requires adjustments to the Conversion Rate under more than one of Sections
11.06(d), 11.07 or 11.08, and the record dates for the distributions giving rise
to such adjustments shall occur on the same date, then such adjustments shall be
made by applying, first, the provisions of Section 11.06, second, the provisions
of Section 11.08 and, third, the provisions of Section 11.07.

      SECTION 11.18. Successive Adjustments. After an adjustment to the
Conversion Rate under this Article 11, any subsequent event requiring an
adjustment under this Article 11 shall cause an adjustment to the Conversion
Rate as so adjusted.

      SECTION 11.19. Rights Issued in Respect of Common Stock Issued Upon
Conversion. Each share of Common Stock issued upon conversion of Securities
pursuant to this Article 11 shall be entitled to receive the appropriate number
of common stock or preferred stock purchase rights, as the case may be (the
"Rights"), if any, that shares of Common Stock are entitled to receive and the
certificates representing the Common Stock issued upon such conversion shall
bear such legends, if any, in each case as may be provided by the terms of any
shareholder rights agreement adopted by the Company, as the same may be amended
from time to time (in each case, a "Rights Agreement"). Provided that such
Rights Agreement requires that each share of Common Stock issued upon conversion
of Securities at any time prior to the distribution of separate certificates
representing the Rights be entitled to receive such Rights, then,
notwithstanding anything else to the contrary in this Article 11, there shall
not be any adjustment to the conversion privilege or Conversion Rate as a result
of the issuance of Rights, the distribution of separate certificates
representing the Rights, the exercise or redemption of such Rights in accordance
with any such Rights Agreement, or the termination or invalidation of such
Rights. ARTICLE XII.

                                  MISCELLANEOUS

      SECTION 12.01. Trust Indenture Act Controls. If any provision of this
Indenture limits, qualifies, or conflicts with another provision which is
required to be included in this Indenture by the TIA, the required provision
shall control.

      SECTION 12.02. Notices. Any request, demand, authorization, notice,
waiver, consent or communication shall be in writing and delivered in person or
mailed by first-class mail, postage prepaid, addressed as follows or transmitted
by facsimile transmission (confirmed by guaranteed overnight courier) to the
following facsimile numbers:

      if to the Company:

            Affiliated Managers Group, Inc.
            Two International Place
            Boston, MA  02100
            Telephone No. (617) 747-3300
            Facsimile No. (617)747-3380
            Attention: Treasurer


                                       59
<PAGE>

      If to the Trustee:

            First Union National Bank
            One World Trade Center
            Suite 4711
            New York, NY 10048
            Telephone No. (212) 938-0779
            Facsimile No. (212) 938-0821
            Attention: Corporate Trust - Bond Administration

      The Company or the Trustee by notice given to the other in the manner
provided above may designate additional or different addresses for subsequent
notices or communications.

      Any notice or communication given to a Securityholder shall be mailed to
the Securityholder, by first-class mail, postage prepaid, at the
Securityholder's address as it appears on the registration books of the
Registrar and shall be sufficiently given if so mailed within the time
prescribed.

      Failure to mail a notice or communication to a Securityholder or any
defect in it shall not affect its sufficiency with respect to other
Securityholders. If a notice or communication is mailed in the manner provided
above, it is duly given, whether or not received by the addressee.

      If the Company mails a notice or communication to the Securityholders, it
shall mail a copy to the Trustee and each Registrar, Paying Agent, Conversion
Agent or co-registrar.

      SECTION 12.03. Communication by Holders with Other Holders.
Securityholders may communicate pursuant to TIA Section 312(b) with other
Securityholders with respect to their rights under this Indenture or the
Securities. The Company, the Trustee, the Registrar, the Paying Agent, the
Conversion Agent and anyone else shall have the protection of TIA Section
312(c).

      SECTION 12.04. Certificate and Opinion as to Conditions Precedent. Upon
any request or application by the Company to the Trustee to take any action
under this Indenture, the Company shall furnish to the Trustee:

      (a) an Officers' Certificate stating that, in the opinion of the signers,
all conditions precedent, if any, provided for in this Indenture relating to the
proposed action have been complied with; and

      (b) an Opinion of Counsel stating that, in the opinion of such counsel,
all such conditions precedent, if any, have been complied with; provided,
however, that an Opinion of Counsel shall not be required upon the initial
issuance of Securities and upon the issuance of Securities pursuant to the
Over-Allotment Option.

      SECTION 12.05. Statements Required in Certificate or Opinion. Each
Officers' Certificate or Opinion of Counsel with respect to compliance with a
covenant or condition provided for in this Indenture shall include:


                                       60
<PAGE>

      (a) a statement that each person making such Officers' Certificate or
Opinion of Counsel has read such covenant or condition;

      (b) a brief statement as to the nature and scope of the examination or
investigation upon which the statements or opinions contained in such Officers'
Certificate or Opinion of Counsel are based;

      (c) a statement that, in the opinion of each such person, he has made such
examination or investigation as is necessary to enable such person to express an
informed opinion as to whether or not such covenant or condition has been
complied with; and

      (d) a statement that, in the opinion of such person, such covenant or
condition has been complied with.

      SECTION 12.06. Separability Clause. In case any provision in this
Indenture or in the Securities shall be invalid, illegal or unenforceable, the
validity, legality and enforceability of the remaining provisions shall not in
any way be affected or impaired thereby.

      SECTION 12.07. Rules by Trustee, Paying Agent, Conversion Agent and
Registrar. The Trustee may make reasonable rules for action by or a meeting of
Securityholders. The Registrar, Conversion Agent and the Paying Agent may make
reasonable rules for their functions.

      SECTION 12.08. Legal Holidays. A "Legal Holiday" is any day other than a
Business Day. If any specified date (including a date for giving notice) is a
Legal Holiday, the action shall be taken on the next succeeding day that is not
a Legal Holiday, and, if the action to be taken on such date is a payment in
respect of the Securities, no Original Issue Discount or interest, if any, shall
accrue for the intervening period.

      SECTION 12.09. GOVERNING LAW. THE LAWS OF THE STATE OF NEW YORK SHALL
GOVERN THIS INDENTURE AND THE SECURITIES, WITHOUT REGARD TO PRINCIPLES OF
CONFLICT OF LAWS.

      SECTION 12.10. No Recourse Against Others. A director, officer, employee
or stockholder, as such, of the Company shall not have any liability for any
obligations of the Company under the Securities or this Indenture or for any
claim based on, in respect of or by reason of such obligations or their
creation. By accepting a Security, each Securityholder shall waive and release
all such liability. The waiver and release shall be part of the consideration
for the issue of the Securities.

      SECTION 12.11. Successors. All agreements of the Company in this Indenture
and the Securities shall bind its successor. All agreements of the Trustee in
this Indenture shall bind its successor.

      SECTION 12.12. Multiple Originals. The parties may sign any number of
copies of this Indenture. Each signed copy shall be an original, but all of them
together represent the same agreement. One signed copy is enough to prove this
Indenture.


                                       61
<PAGE>

      IN WITNESS WHEREOF, the undersigned, being duly authorized, have executed
this Indenture on behalf of the respective parties hereto as of the date first
above written.

                                    AFFILIATED MANAGERS GROUP, INC.

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


                                    FIRST UNION NATIONAL BANK, as Trustee

                                    By /s/ David Massa
                                       ----------------------------------
                                       Name:  David Massa
                                       Title: Vice President


                                       62
<PAGE>

                                   EXHIBIT A-1

                        [FORM OF FACE OF GLOBAL SECURITY]

FOR PURPOSES OF SECTIONS 1273 AND 1275 OF THE INTERNAL REVENUE CODE, THE AMOUNT
OF ORIGINAL ISSUE DISCOUNT WITH RESPECT TO EACH $1,000 OF PRINCIPAL AMOUNT AT
MATURITY OF THIS SECURITY IS $95.05, THE ISSUE DATE IS MAY 7, 2001, THE YIELD TO
MATURITY IS 0.50%.

      UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF
THE DEPOSITORY TRUST COMPANY TO THE ISSUER OR ITS AGENT FOR REGISTRATION OF
TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE
NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED
REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (AND ANY PAYMENT HEREON IS MADE
TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED
REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY), ANY TRANSFER PLEDGE OR OTHER
USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL SINCE THE
REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

      TRANSFERS OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS IN WHOLE,
BUT NOT IN PART, TO NOMINEES OF THE DEPOSITORY TRUST COMPANY, OR TO A SUCCESSOR
THEREOF OR SUCH SUCCESSOR'S NOMINEE AND TRANSFERS OF PORTIONS OF THIS GLOBAL
SECURITY SHALL BE LIMITED TO TRANSFERS MADE IN ACCORDANCE WITH THE RESTRICTIONS
SET FORTH IN ARTICLE TWO OF THE INDENTURE REFERRED TO ON THE REVERSE HEREOF.

      THIS SECURITY AND THE SHARES OF COMMON STOCK ISSUABLE UPON CONVERSION OF
THIS SECURITY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED (THE "SECURITIES ACT"), OR ANY STATE SECURITIES LAWS. NEITHER THIS
SECURITY, THE SHARES OF COMMON STOCK ISSUABLE UPON CONVERSION OF THIS SECURITY
NOR ANY INTEREST OR PARTICIPATION HEREIN OR THEREIN MAY BE REOFFERED, SOLD,
ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE
ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT
SUBJECT TO, REGISTRATION.

      THE HOLDER OF THIS SECURITY, BY ITS ACCEPTANCE HEREOF, AGREES TO OFFER,
SELL OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE "RESALE
RESTRICTION TERMINATION DATE") WHICH IS TWO YEARS AFTER THE LATER OF THE
ORIGINAL ISSUE DATE HEREOF AND THE LAST DATE ON WHICH AFFILIATED MANAGERS GROUP,
INC. (THE "COMPANY" OR THE "ISSUER") OR ANY AFFILIATE OF THE COMPANY WAS THE
OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF SUCH SECURITY) ONLY (A) TO THE
COMPANY OR ANY SUBSIDIARY THEREOF, (B) FOR SO LONG AS THIS SECURITY AND THE
SHARES OF


                                     A-1-1
<PAGE>

COMMON STOCK ISSUABLE UPON CONVERSION OF THIS SECURITY ARE ELIGIBLE FOR RESALE
PURSUANT TO RULE 144A, TO A PERSON IT REASONABLY BELIEVES IS A "QUALIFIED
INSTITUTIONAL BUYER" AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT THAT
PURCHASES FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL
BUYER TO WHICH NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN RELIANCE ON
RULE 144A, (C) TO AN INSTITUTIONAL "ACCREDITED INVESTOR" WITHIN THE MEANING OF
SUBPARAGRAPH (A)(1), (2),(3) OR (7) OF RULE 501 UNDER THE SECURITIES ACT THAT IS
ACQUIRING THE SECURITY FOR ITS OWN ACCOUNT, OR FOR THE ACCOUNT OF SUCH AN
INSTITUTIONAL "ACCREDITED INVESTOR," FOR INVESTMENT PURPOSES AND NOT WITH A VIEW
TO, OR FOR OFFER OR SALE IN CONNECTION WITH, ANY DISTRIBUTION IN VIOLATION OF
THE SECURITIES ACT, (D) PURSUANT TO A REGISTRATION STATEMENT WHICH HAS BEEN
DECLARED EFFECTIVE UNDER THE SECURITIES ACT, (E) IN AN OFFSHORE TRANSACTION IN
ACCORDANCE WITH RULE 904 OF REGULATION S UNDER THE SECURITIES ACT OR (F)
PURSUANT TO ANOTHER AVAILABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF
THE SECURITIES ACT, SUBJECT TO THE COMPANY'S AND THE TRUSTEE'S RIGHTS PRIOR TO
ANY SUCH OFFER, SALE OR TRANSFER PURSUANT TO CLAUSE (C), (E) OR (F) TO REQUIRE
THE DELIVERY OF AN OPINION OF COUNSEL, CERTIFICATION AND/OR OTHER INFORMATION
SATISFACTORY TO EACH OF THEM, AND IN EACH OF THE FOREGOING CASES, A CERTIFICATE
OF TRANSFER IN THE FORM APPEARING ON THE OTHER SIDE OF THIS SECURITY IS
COMPLETED AND DELIVERED BY THE TRANSFEROR TO THE TRUSTEE. THIS LEGEND WILL BE
REMOVED UPON THE REQUEST OF THE HOLDER AFTER THE RESALE RESTRICTION TERMINATION
DATE.

      [THE FOREGOING LEGEND MAY BE REMOVED FROM THIS SECURITY ON SATISFACTION OF
THE CONDITIONS SPECIFIED IN THE INDENTURE.]


                                     A-1-2
<PAGE>

                         AFFILIATED MANAGERS GROUP, INC.

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

No. R-1                                  CUSIP:  008252AA6
Issue Date: May 7, 2001                  Original Issue Discount: $95.05
Issue Price: $904.95 (for each $1,000    (for each $1,000 Principal Amount at
Principal Amount at Maturity)            Maturity)

      AFFILIATED MANAGERS GROUP, INC., a Delaware corporation, promises to pay
to CEDE & Co., or registered assigns, the Principal Amount at Maturity of ONE
HUNDRED NINETY FIVE MILLION DOLLARS ($195,000,000) on May 7, 2021.

      This Security shall not bear interest except as specified on the other
side of this Security. Original Issue Discount will accrue as specified on the
other side of this Security. This Security is convertible as specified on the
other side of this Security.

      Additional provisions of this Security are set forth on the other side of
this Security.

Dated: May 7, 2001                  AFFILIATED MANAGERS GROUP, INC.


                                    By ______________________________________
                                       Name:
                                       Title:

Attest:


________________________
Name:
Title:

TRUSTEE'S CERTIFICATE OF
  AUTHENTICATION

FIRST UNION NATIONAL BANK, as Trustee,
certifies that this is one of the
Securities referred to in the within-
mentioned Indenture.


By ______________________
   Authorized Signatory

Dated: May 7, 2001


                                     A-1-3
<PAGE>

                         [FORM OF REVERSE SIDE OF LYON]

                      Liquid Yield Option(TM) Note Due 2021
                              (Zero Coupon-Senior)

1. Interest.

      This Security shall not bear interest, except as specified in this
paragraph or in paragraph 10 hereof. If the Principal Amount at Maturity hereof
or any portion of such Principal Amount at Maturity is not paid when due
(whether upon acceleration pursuant to Section 6.02 of the Indenture, upon the
date set for payment of the Redemption Price pursuant to paragraph 5 hereof,
upon the date set for payment of the Purchase Price or Change in Control
Purchase Price pursuant to paragraph 6 hereof or upon the Stated Maturity of
this Security) (or if interest due hereon or any portion of such interest is not
paid when due in accordance with paragraph 10 hereof), then in each such case
the overdue amount shall, to the extent permitted by law, bear interest at the
rate of 0.50% per annum, compounded semi-annually, which interest shall accrue
from the date such overdue amount was originally due to the date payment of such
amount, including interest thereon, has been made or duly provided for. All such
interest shall be payable on demand. The accrual of such interest on overdue
amounts shall be in lieu of, and not in addition to, the continued accrual of
Original Issue Discount.

      Original Issue Discount (the difference between the Issue Price and the
Principal Amount at Maturity of the Security), in the period during which a
Security remains outstanding, shall accrue at 0.50% per annum, on a semiannual
bond equivalent basis using a 360-day year comprised of twelve 30-day months,
from the Issue Date of this Security.

2. Method of Payment.

      Subject to the terms and conditions of the Indenture, the Company will
make payments in respect of Redemption Price, Purchase Price, Change in Control
Purchase Price, Restated Principal Amount and at Stated Maturity to Holders who
surrender Securities to a Paying Agent to collect such payments in respect of
the Securities. The Company will pay cash amounts in money of the United States
that at the time of payment is legal tender for payment of public and private
debts. However, the Company may make such cash payments by check payable in such
money; provided that payment by wire transfer of immediately available funds
will be required with respect to principal of and interest, if any, on all
Global Securities and all other Securities the Holders of which shall have
provided wire transfer instructions to the Company or the Paying Agent. Any
payment required to be made on any day that is not a Business Day will be made
on the next succeeding Business Day.

3. Paying Agent, Conversion Agent and Registrar.

      Initially, First Union National Bank, a national banking association (the
"Trustee"), will act as Paying Agent, Conversion Agent and Registrar. The
Company may appoint and change

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


                                     A-1-4
<PAGE>

any Paying Agent, Conversion Agent, Registrar or co-registrar without notice,
other than notice to the Trustee except that the Company will maintain at least
one Paying Agent in the State of New York, City of New York, Borough of
Manhattan, which shall initially be an office or agency of the Trustee. The
Company or any of its Subsidiaries or any of their Affiliates may act as Paying
Agent, Conversion Agent, Registrar or co-registrar.

4. Indenture.

      The Company issued the Securities under an Indenture dated as of May 7,
2001 (the "Indenture"), between the Company and the Trustee. The terms of the
Securities include those stated in the Indenture and those made part of the
Indenture by reference to the Trust Indenture Act of 1939, as in effect from
time to time (the "TIA"). Capitalized terms used herein and not defined herein
have the meanings ascribed thereto in the Indenture. The Securities are subject
to all such terms, and Securityholders are referred to the Indenture and the TIA
for a statement of those terms.

      The Securities are general unsecured obligations of the Company limited to
$195,000,000 aggregate Principal Amount at Maturity (subject to Sections 2.02
and 2.07 of the Indenture). The Indenture does not limit other indebtedness of
the Company, secured or unsecured.

5. Redemption at the Option of the Company.

      No sinking fund is provided for the Securities. The Securities are
redeemable as a whole, or from time to time in part, at any time at the option
of the Company at the Redemption Prices set forth below, provided that the
Securities are not redeemable prior to May 7, 2006.

      The table below shows Redemption Prices of a Security per $1,000 Principal
Amount at Maturity on the dates shown below and at Stated Maturity, which prices
reflect accrued Original Issue Discount calculated to each such date. The
Redemption Price of a Security redeemed between such dates shall include an
additional amount reflecting the additional Original Issue Discount accrued
since the preceding date in the table through the date of redemption.

                                                        (2)
                                         (1)          ORIGINAL         (3)
                                         LYON          ISSUE        REDEMPTION
                                        ISSUE       DISCOUNT AT       PRICE
REDEMPTION DATE                         PRICE           0.5%        (1) + (2)
---------------------------------      -------      -----------     ----------

May 7, 2006......................      $904.95         $22.88        $927.83
May 7, 2007......................      $904.95         $27.52        $932.47
May 7, 2008......................      $904.95         $32.19        $937.14
May 7, 2009......................      $904.95         $36.88        $941.83
May 7, 2010......................      $904.95         $41.60        $946.55
May 7, 2011......................      $904.95         $46.34        $951.29
May 7, 2012......................      $904.95         $51.10        $956.05
May 7, 2013......................      $904.95         $55.89        $960.84
May 7, 2014......................      $904.95         $60.70        $965.65


                                     A-1-5
<PAGE>

                                                        (2)
                                         (1)          ORIGINAL         (3)
                                         LYON          ISSUE        REDEMPTION
                                        ISSUE       DISCOUNT AT       PRICE
REDEMPTION DATE                         PRICE           0.5%        (1) + (2)
---------------------------------      -------      -----------     ----------

May 7, 2015......................      $904.95         $65.53        $970.48
May 7, 2016......................      $904.95         $70.39        $975.34
May 7, 2017......................      $904.95         $75.27        $980.22
May 7, 2018......................      $904.95         $80.18        $985.13
May 7, 2019......................      $904.95         $85.11        $990.06
May 7, 2020......................      $904.95         $90.07        $995.02
At stated maturity...............      $904.95         $95.05      $1,000.00

If converted to a semiannual coupon note following the occurrence of a Tax
Event, this Security will be redeemable at a Redemption Price equal to the
Restated Principal Amount plus accrued and unpaid interest from the date of such
conversion through the Redemption Date; but in no event will this Security be
redeemable before May 7, 2006.

6. Purchase By the Company at the Option of the Holder.

      Subject to the terms and conditions of the Indenture, the Company shall
become obligated to purchase, at the option of the Holder, the Securities held
by such Holder on the following Purchase Dates and at the following Purchase
Prices per $1,000 Principal Amount at Maturity, upon delivery of a Purchase
Notice containing the information set forth in the Indenture, at any time from
the opening of business on the date that is 30 Business Days prior to such
Purchase Date until the close of business on such Purchase Date and upon
delivery of the Securities to the Paying Agent by the Holder as set forth in the
Indenture.

                   Purchase Date        Purchase Price
                   -------------        --------------
                    May 7, 2002            $909.48
                    May 7, 2004            $918.61
                    May 7, 2006            $927.83
                    May 7, 2011            $951.29
                    May 7, 2016            $975.34

      The Purchase Price (equal to the Issue Price plus accrued Original Issue
Discount to the Purchase Date) may be paid, at the option of the Company, in
cash or by the issuance and delivery of shares of Common Stock of the Company,
or in any combination thereof.

      If prior to a Purchase Date this Security has been converted to a
semiannual coupon note following the occurrence of a Tax Event, the Purchase
Price will be equal to the Restated Principal Amount plus accrued and unpaid
interest from the date of conversion to the Purchase Date.

      At the option of the Holder and subject to the terms and conditions of the
Indenture, the Company shall become obligated to purchase all or a portion of
the Securities held by such


                                     A-1-6
<PAGE>

Holder as of the date that is 35 Business Days after the occurrence of a Change
in Control of the Company occurring on or prior to May 7, 2006 for a Change in
Control Purchase Price equal to the Issue Price plus accrued Original Issue
Discount to the Change in Control Purchase Date, which Change in Control
Purchase Price shall be paid in cash.

      If prior to a Change in Control Purchase Date this Security has been
converted to a semiannual coupon note following the occurrence of a Tax Event,
the Change in Control Purchase Price shall be equal to the Restated Principal
Amount plus accrued and unpaid interest from the date of conversion to the
Change in Control Purchase Date.

      Holders have the right to withdraw any Purchase Notice or Change in
Control Purchase Notice, as the case may be, by delivering to the Paying Agent a
written notice of withdrawal in accordance with the provisions of the Indenture.

      If cash (and/or securities if permitted under the Indenture) sufficient to
pay the Purchase Price or Change in Control Purchase Price, as the case may be,
of all Securities or portions thereof to be purchased as of the Purchase Date or
the Change in Control Purchase Date, as the case may be, is deposited with the
Paying Agent on the Business Day following the Purchase Date or the Change in
Control Purchase Date, as the case may be, Original Issue Discount ceases to
accrue on such Securities (or portions thereof) immediately after such Purchase
Date or Change in Control Purchase Date, as the case may be, and the Holder
thereof shall have no other rights as such (other than the right to receive the
Purchase Price or Change in Control Purchase Price, as the case may be, upon
surrender of such Security).

7. Notice of Redemption.

      Notice of redemption will be mailed at least 15 days but not more than 60
days before the Redemption Date to each Holder of Securities to be redeemed at
the Holder's registered address. If money sufficient to pay the Redemption Price
of all Securities (or portions thereof) to be redeemed on the Redemption Date is
deposited with the Paying Agent prior to or on the Redemption Date, immediately
after such Redemption Date Original Issue Discount ceases to accrue on such
Securities or portions thereof. Securities in denominations larger than $1,000
of Principal Amount at Maturity may be redeemed in part but only in integral
multiples of $1,000 of Principal Amount at Maturity.

8. Conversion.

      (a) Conversion Based on Common Stock Price. Subject to the provisions of
this paragraph 8 and notwithstanding the fact that any other condition to
conversion has not been satisfied, Holders may convert the Securities into
Common Stock on a Conversion Date in any fiscal quarter commencing after June
30, 2001, if, as of the last day of the preceding fiscal quarter, the Sale Price
of the Common Stock for at least 20 trading days in a period of 30 consecutive
trading days ending on the last trading day of such preceding fiscal quarter is
greater than the conversion trigger price. The "conversion trigger price" for
any fiscal quarter shall be a reference percentage, beginning at 120%, and
declining 0.12658% per quarter thereafter until it reaches 110.00018% for the
quarter beginning April 1, 2021, of the accreted conversion price per share of
Common Stock on the last trading day of such preceding calendar quarter.


                                     A-1-7
<PAGE>

      The "accreted conversion price" per share of Common Stock as of any day
equals the quotient of:

            o     the Issue Price and accrued Original Issue Discount to that
                  day, divided by

            o     the number of shares of Common Stock issuable upon conversion
                  of $1,000 Principal Amount at Maturity of Securities on that
                  day.

      For illustrative purposes only, the table below shows the conversion
trigger price per share of Common Stock in respect of each of the first 20
fiscal quarters following issuance of the Securities. The conversion trigger
price for any fiscal quarter starting on or after June 30, 2001 shall be the
conversion trigger price as of the last day of the immediately preceding fiscal
quarter as set forth in the table below. These conversion trigger prices reflect
the accreted conversion price per share of Common Stock (assuming that no events
occurred requiring an adjustment to the initial Conversion Rate of 11.6195
shares of Common Stock per $1,000 Principal Amount of Maturity) multiplied by
the applicable percentage for the respective fiscal quarter. Thereafter, the
accreted conversion price per share of Common Stock increases each fiscal
quarter by the accrued Original Issue Discount for the quarter and the
applicable percentage declines by 0.12658% per quarter. The conversion trigger
price for the calendar quarter beginning April 1, 2021 is $94.62.

                                          (1)            (2)            (3)
                                        Accreted                    Conversion
                                       Conversion     Applicable   Trigger Price
Calendar Quarter                         Price        Percentage     (1) X (2)
----------------                         -----        ----------     ---------

2001
   Quarter ended September 30, 2001      77.94        120.00000%      $93.53
   Quarter ended December 31, 2001       78.04        119.87342%      $93.55
2002
   Quarter ended March 31, 2002          78.14        119.74684%      $93.56
   Quarter ended June 30, 2002           78.23        119.62026%      $93.58
   Quarter ended September 30, 2002      78.33        119.49368%      $93.60
   Quarter ended December 31, 2002       78.43        119.36710%      $93.62
2003
   Quarter ended March 31, 2003          78.53        119.24052%      $93.64
   Quarter ended June 30, 2003           78.62        119.11394%      $93.65
   Quarter ended September 30, 2003      78.72        118.98736%      $93.67
   Quarter ended December 31, 2003       78.82        118.86078%      $93.69
2004
   Quarter ended March 31, 2004          78.92        118.73420%      $93.70
   Quarter ended June 30, 2004           79.02        118.60762%      $93.72
   Quarter ended September 30, 2004      79.12        118.48104%      $93.74
   Quarter ended December 31, 2004       79.22        118.35446%      $93.76
2005
   Quarter ended March 31, 2005          79.31        118.22788%      $93.77
   Quarter ended June 30, 2005           79.41        118.10130%      $93.79
   Quarter ended September 30, 2005      79.51        117.97472%      $93.81
   Quarter ended December 31, 2005       79.61        117.84814%      $93.82
2006
   Quarter ended March 31, 2006          79.71        117.72156%      $93.84
   Quarter ended June 30, 2006           79.81        117.59498%      $93.85

--------------------
*     This table assumes no events occurred that would require an adjustment to
      the conversion rate.


                                     A-1-8
<PAGE>

      (b) Conversion Based on Credit Rating. Subject to the provisions of
this paragraph 8 and notwithstanding the fact any other condition to
conversion has not been satisfied, Holders may convert the Securities into
Common Stock on a Conversion Date during any period in which the credit
rating assigned to the Securities by Standard & Poor's Ratings Services, a
division of The McGraw-Hill Companies Inc., and its successors ("Standard &
Poor's") or if Standard & Poor's is not making ratings of the Securities
publicly available, a nationally recognized U.S. rating agency or agencies,
as the case may be, selected by the Company, which will be substituted for
Standard & Poor's, is below the Applicable Rating. "Applicable Rating" means,
(1) BB-, in the case of Standard & Poor's (or its equivalent, under any
successor ratings categories of Standard & Poor's) or (2) the equivalent in
respect of ratings categories of any rating agencies substituted for Standard
& Poor's.

      (c) Conversion Based on Redemption. Subject to the provisions of this
paragraph 8 and notwithstanding the fact that any other condition to conversion
has not been satisfied, a Holder may convert into Common Stock a Security or
portion of a Security which has been called for redemption pursuant to paragraph
6 hereof, even if the foregoing provisions have not been satisfied, but such
Securities may be surrendered for conversion until the close of business on the
second Business Day immediately preceding the Redemption Date.

      (d) Conversion Upon Occurrence of Certain Corporate Transactions. Subject
to the provisions of this paragraph 8 and notwithstanding the fact that any
other condition to conversion has not been satisfied, in the event that the
Company declares a dividend or distribution described in Section 11.07 of the
Indenture, or a dividend or a distribution described in Section 11.08 of the
Indenture where the fair market value of such dividend or distribution per share
of Common Stock, as determined in the Indenture, exceeds 15% of the Sale Price
of the Common Stock on the Business Day immediately preceding the date of
declaration for such dividend or distribution, the Securities may be surrendered
for conversion beginning on the date the Company gives notice to the Holders of
such right, which shall not be less than 20 days prior to the Ex-Dividend Time
for such dividend or distribution, and Securities may be surrendered for
conversion at any time thereafter until the close of business on the Business
Day prior to the Ex-Dividend Time or until the Company announces that such
dividend or distribution will not take place.

      Subject to the provisions of this paragraph 8 and notwithstanding the fact
that any other condition to conversion has not been satisfied, in the event the
Company is a party to a consolidation, merger or binding share exchange or a
transfer of all or substantially all assets of the Company pursuant to which the
Common Stock would be converted into cash, securities or other property as set
forth in Section 11.14 of the Indenture, the Securities may be surrendered for
conversion at any time from and after the date which is 15 days prior to the
date the Company announces the anticipated effective time until 15 days after
the actual effective date of such transaction, and at the effective time of such
transaction the right to convert a Security into Common Stock will be deemed to
have changed into a right to convert it into the kind and amount of cash,
securities or other property which the holder would have received if the holder
had converted its Security immediately prior to the transaction.

      A Security in respect of which a Holder has delivered a Purchase Notice or
Change in Control Purchase Notice exercising the option of such Holder to
require the Company to


                                     A-1-9
<PAGE>

purchase such Security may be converted only if such notice of exercise is
withdrawn in accordance with the terms of the Indenture.

      The initial Conversion Rate is 11.6195 shares of Common Stock per $1,000
Principal Amount at Maturity, subject to adjustment in certain events described
in the Indenture. The Company will deliver cash or a check in lieu of any
fractional share of Common Stock.

      In the event the Company exercises its option pursuant to Section 10.01 of
the Indenture to have interest in lieu of Original Issue Discount accrue on the
Security following a Tax Event, the Holder will be entitled on conversion to
receive the same number of shares of Common Stock such Holder would have
received if the Company had not exercised such option. Accrued and unpaid
interest in lieu of Original Issue Discount will not be paid on Securities that
are converted; provided, however, that Securities surrendered for conversion
during the period, in the case of interest in lieu of Original Issue Discount,
from the close of business on any Regular Record Date next preceding any
Interest Payment Date to the opening of business on such Interest Payment Date
shall be entitled to receive such interest, in lieu of Original Issue Discount,
payable on such Securities on the corresponding Interest Payment Date and
(except Securities with respect to which the Company has mailed a notice of
redemption) Securities surrendered for conversion during such periods must be
accompanied by payment of an amount equal to the interest in lieu of Original
Issue Discount with respect thereto that the registered Holder is to receive.

      To convert a Security, a Holder must (1) complete and manually sign the
conversion notice below (or complete and manually sign a facsimile of such
notice) and deliver such notice to the Conversion Agent, (2) surrender the
Security to the Conversion Agent, (3) furnish appropriate endorsements and
transfer documents if required by the Conversion Agent, the Company or the
Trustee and (4) pay any transfer or similar tax, if required.

      A Holder may convert a portion of a Security if the Principal Amount at
Maturity of such portion is $1,000 or an integral multiple of $1,000. No payment
or adjustment will be made for dividends on the Common Stock except as provided
in the Indenture. On conversion of a Security, that portion of accrued Original
Issue Discount (or interest if the Company has exercised its option provided for
in paragraph 10 hereof) attributable to the period from the Issue Date (or, if
the Company has exercised the option referred to in paragraph 10 hereof, the
later of (x) the date of such exercise and (y) the date on which interest was
last paid) through the Conversion Date with respect to the converted Security
shall not be canceled, extinguished or forfeited, but rather shall be deemed to
be paid in full to the Holder thereof through the delivery of the Common Stock
(together with the cash payment, if any, in lieu of fractional shares) in
exchange for the Security being converted pursuant to the terms hereof; and the
fair market value of such shares of Common Stock (together with any such cash
payment in lieu of fractional shares) shall be treated as issued, to the extent
thereof, first in exchange for Original Issue Discount (or interest, if the
Company has exercised its option provided for in paragraph 10 hereof) accrued
through the Conversion Date, and the balance, if any, of such fair market value
of such Common Stock (and any such cash payment) shall be treated as issued in
exchange for the Issue Price of the Security being converted pursuant to the
provisions hereof.


                                     A-1-10
<PAGE>

      The Conversion Rate will be adjusted for dividends or distributions on
Common Stock payable in Common Stock or other Capital Stock; subdivisions,
combinations or certain reclassifications of Common Stock; distributions to all
holders of Common Stock of certain rights to purchase Common Stock for a period
expiring within 60 days at less than the Sale Price at the Time of
Determination; and distributions to such holders of assets or debt securities of
the Company or certain rights to purchase securities of the Company (excluding
certain cash dividends or distributions). However, no adjustment need be made if
Securityholders may participate in the transaction or in certain other cases.
The Company from time to time may voluntarily increase the Conversion Rate.

      If the Company is a party to a consolidation, merger or binding share
exchange or a transfer of all or substantially all of its assets, or upon
certain distributions described in the Indenture, the right to convert a
Security into Common Stock may be changed into a right to convert it into
securities, cash or other assets of the Company or another person.

9. Conversion Arrangement on Call for Redemption.

      Any Securities called for redemption, unless surrendered for conversion
before the close of business on the Redemption Date, may be deemed to be
purchased from the Holders of such Securities at an amount not less than the
Redemption Price, by one or more investment bankers or other purchasers who may
agree with the Company to purchase such Securities from the Holders, to convert
them into Common Stock of the Company and to make payment for such Securities to
the Trustee in trust for such Holders.

10. Tax Event

      (a) From and after the later of (i) the date (the "Tax Event Date") of the
occurrence of a Tax Event or (ii) the date the Company exercises such option
(the "Option Exercise Date"), at the option of the Company, interest in lieu of
future Original Issue Discount shall accrue at the rate of 0.50% per annum on a
principal amount per Security (the "Restated Principal Amount") equal to the
Issue Price plus Original Issue Discount accrued through the Option Exercise
Date and shall be payable semiannually on May 7 and November 7 of each year
(each an "Interest Payment Date") to holders of record at the close of business
on April 21 or October 22 (each a "Regular Record Date") immediately preceding
such Interest Payment Date. Interest will be computed on the basis of a 360-day
year comprised of twelve 30-day months and will accrue from the most recent date
to which interest has been paid or, if no interest has been paid, from the
Option Exercise Date.

      (b) Interest on any Security that is payable, and is punctually paid or
duly provided for, on any Interest Payment Date shall be paid to the person in
whose name that Security is registered at the close of business on the Regular
Record Date for such interest at the office or agency of the Company maintained
for such purpose. Each installment of interest on any Security shall be paid by
check; provided that payment by wire transfer of immediately available funds
will be required with respect to principal on and interest, if any, on all
Global Securities and all other Securities the holders of which shall have
provided wire transfer instructions to the Company or the Paying Agent for an
account maintained by the payee located inside the United States.


                                     A-1-11
<PAGE>

      (c) Except as otherwise specified with respect to the Securities, any
Defaulted Interest on any Security shall forthwith cease to be payable to the
registered Holder thereof on the relevant Regular Record Date by virtue of
having been such Holder, and such Defaulted Interest may be paid by the Company
as provided for in Section 10.02(b) of the Indenture.

11. Denominations; Transfer; Exchange.

      The Securities are in fully registered form, without coupons, in
denominations of $1,000 of Principal Amount at Maturity and integral multiples
of $1,000. A Holder may transfer or exchange Securities in accordance with the
Indenture. The Registrar may require a Holder, among other things, to furnish
appropriate endorsements and transfer documents and to pay any taxes and fees
required by law or permitted by the Indenture. The Registrar need not transfer
or exchange any Securities selected for redemption (except, in the case of a
Security to be redeemed in part, the portion of the Security not to be redeemed)
or any Securities in respect of which a Purchase Notice or Change in Control
Purchase Notice has been given and not withdrawn (except, in the case of a
Security to be purchased in part, the portion of the Security not to be
purchased) or any Securities for a period of 15 days before the mailing of a
notice of redemption of Securities to be redeemed.

12. Persons Deemed Owners.

      The registered Holder of this Security may be treated as the owner of this
Security for all purposes.

13. Unclaimed Money or Securities.

      The Trustee and the Paying Agent shall return to the Company upon written
request any money or securities held by them for the payment of any amount with
respect to the Securities that remains unclaimed for two years subject to
applicable unclaimed property law. After return to the Company, Holders entitled
to the money or securities must look to the Company for payment as general
creditors unless an applicable abandoned property law designates another person.

14. Amendment; Waiver.

      Subject to certain exceptions set forth in the Indenture, (i) the
Indenture or the Securities may be amended with the written consent of the
Holders of at least a majority in aggregate Principal Amount at Maturity of the
Securities at the time outstanding and (ii) certain Defaults may be waived with
the written consent of the Holders of a majority in aggregate Principal Amount
at Maturity of the Securities at the time outstanding. Subject to certain
exceptions set forth in the Indenture, without the consent of any
Securityholder, the Company and the Trustee may amend the Indenture or the
Securities to cure any ambiguity, omission, defect or inconsistency, or to
comply with Article 5 or Section 11.14 of the Indenture, to provide for
uncertificated Securities in addition to or in place of certificated Securities
or to make any change that does not adversely affect the rights of any
Securityholder, or to comply with any requirement of the SEC in connection with
the qualification of the Indenture under the TIA.


                                     A-1-12
<PAGE>

15. Defaults and Remedies.

      Under the Indenture, Events of Default include (i) if the Securities have
been converted to semiannual coupon notes following a Tax Event, default in the
payment of interest which default continues for a period of 30 days; (ii)
default in payment of the Principal Amount at Maturity (or, if the Securities
have been converted to semiannual coupon notes following a Tax Event, the
Restated Principal Amount), Issue Price plus accrued Original Issue Discount,
Redemption Price, Purchase Price or Change in Control Purchase Price, as the
case may be, in respect of the Securities when the same becomes due and payable;
(iii) failure by the Company to comply with other agreements in the Indenture or
the Securities, subject to notice and lapse of time; (iv) default under any
Debt, whether such Debt now exists or is created later, which default results in
such Debt becoming or being declared due and payable prior to the date on which
it would otherwise have become due and payable, and the principal amount of all
Debt so accelerated, together with all Debt due and payable but not paid prior
to the end of any grace period, is $30,000,000 or more, and such acceleration
has not been rescinded or annulled within a period of 30 days after receipt by
the Company of a Notice of Default, subject to notice and lapse of time;
provided, however, that if any such default shall be cured, waived, rescinded or
annulled, then the Event of Default by reason thereof shall be deemed not to
have occurred; (v) final unsatisfied judgments not covered by insurance
aggregating in excess of $30,000,000 rendered against the Company and not
stayed, bonded or discharged within 60 days; and (vi) certain events of
bankruptcy or insolvency. If an Event of Default occurs and is continuing, the
Trustee, or the Holders of at least 25% in aggregate Principal Amount at
Maturity of the Securities at the time outstanding, may declare all the
Securities to be due and payable immediately. Certain events of bankruptcy or
insolvency are Events of Default which will result in the Securities becoming
due and payable immediately upon the occurrence of such Events of Default.

      Holders may not enforce the Indenture or the Securities except as provided
in the Indenture. The Trustee may refuse to enforce the Indenture or the
Securities unless it receives reasonable indemnity or security. Subject to
certain limitations, Holders of a majority in aggregate Principal Amount at
Maturity of the Securities at the time outstanding may direct the Trustee in its
exercise of any trust or power. The Trustee may withhold from Securityholders
notice of any continuing Default (except a Default in payment of amounts
specified in clause (i) or (ii) above) if it determines that withholding notice
is in their interests.

16. Trustee Dealings with the Company.

      Subject to certain limitations imposed by the TIA, the Trustee under the
Indenture, in its individual or any other capacity, may become the owner or
pledgee of Securities and may otherwise deal with and collect obligations owed
to it by the Company or its Affiliates and may otherwise deal with the Company
or its Affiliates with the same rights it would have if it were not Trustee.

17. No Recourse Against Others.

      A director, officer, employee or stockholder, as such, of the Company
shall not have any liability for any obligations of the Company under the
Securities or the Indenture or for any


                                     A-1-13
<PAGE>

claim based on, in respect of or by reason of such obligations or their
creation. By accepting a Security, each Securityholder waives and releases all
such liability. The waiver and release are part of the consideration for the
issue of the Securities.

18. Authentication.

      This Security shall not be valid until an authorized signatory of the
Trustee manually signs the Trustee's Certificate of Authentication on the other
side of this Security.

19. Abbreviations.

      Customary abbreviations may be used in the name of a Securityholder or an
assignee, such as TEN COM (=tenants in common), TEN ENT (=tenants by the
entireties), JT TEN (=joint tenants with right of survivorship and not as
tenants in common), CUST (=custodian), and U/G/M/A (=Uniform Gift to Minors
Act).

20. GOVERNING LAW.

      THE LAWS OF THE STATE OF NEW YORK SHALL GOVERN THE INDENTURE AND THIS
SECURITY, WITHOUT REGARD TO PRINCIPLES OF CONFLICT OF LAWS.

                                   ----------

      The Company will furnish to any Securityholder upon written request and
without charge a copy of the Indenture.

            Affiliated Managers Group, Inc.
            Two International Place
            Boston, MA 02110
            Telephone No. (617) 747-3300
            Facsimile No. (617) 747-3380
            Attention: Treasurer


                                     A-1-14
<PAGE>

            ASSIGNMENT FORM                         CONVERSION NOTICE

To assign this Security, fill in the     To convert this Security into Common
form below:                              Stock of the Company, check the box:|_|

I or we assign and transfer this         To convert only part of this Security,
Security to                              state the Principal Amount at Maturity
                                         to be converted (which must be $1,000
___________________________________      or an integral multiple of $1,000):
                                         $___________________________

___________________________________      If you want the stock certificate made
(Insert assignee's soc. sec. or          out in another person's name, fill in
         tax ID no.)                     the form below:

___________________________________
                                         ___________________________________
___________________________________
(Print or type assignee's name, address  ___________________________________
             and zip code)
                                         (Insert other person's soc. sec. or
and irrevocably appoint _____________    tax ID no.)
agent to transfer this Security on the   ___________________________________
books of the Company.  The agent may
substitute another to act for him.       ___________________________________
                                         (Print or type other person's name,
                                         address and zip code)

Date: ___________________________        Your
                                         Signature: ___________________________*
                                         (Sign exactly as your name appears on
                                         the other side of this Security)


* Your signature must be guaranteed by an "eligible guarantor institution"
meeting the requirements of the Trustee, which requirements include membership
or participation in the Security Transfer Agent Medallion Program ("STAMP") or
such other "signature guarantee program" as may be determined by the Trustee in
addition to, or in substitution for, STAMP, all in accordance with the
Securities Exchange Act of 1934, as amended.


                                     A-1-15
<PAGE>

                                   EXHIBIT A-2

                         [Form of Certificated Security]

FOR PURPOSES OF SECTIONS 1273 AND 1275 OF THE INTERNAL REVENUE CODE, THE AMOUNT
OF ORIGINAL ISSUE DISCOUNT WITH RESPECT TO EACH $1,000 OF PRINCIPAL AMOUNT AT
MATURITY OF THIS SECURITY IS $95.05, THE ISSUE DATE IS MAY 7, 2001, THE YIELD TO
MATURITY IS 0.50%.

      [INCLUDE IF SECURITY IS A CERTIFICATED SECURITY TO BE HELD BY AN
INSTITUTIONAL ACCREDITED INVESTOR--IN CONNECTION WITH ANY TRANSFER, THE HOLDER
WILL DELIVER TO THE REGISTRAR AND TRANSFER AGENT SUCH CERTIFICATES AND OTHER
INFORMATION AS SUCH TRANSFER AGENT MAY REASONABLY REQUIRE TO CONFIRM THAT THE
TRANSFER COMPLIES WITH THE FOLLOWING RESTRICTIONS.]

      THIS SECURITY AND THE SHARES OF COMMON STOCK ISSUABLE UPON CONVERSION OF
THIS SECURITY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED (THE "SECURITIES ACT"), OR ANY STATE SECURITIES LAWS. NEITHER THIS
SECURITY, THE SHARES OF COMMON STOCK ISSUABLE UPON CONVERSION OF THIS SECURITY
NOR ANY INTEREST OR PARTICIPATION HEREIN OR THEREIN MAY BE REOFFERED, SOLD,
ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE
ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT
SUBJECT TO, REGISTRATION.

      THE HOLDER OF THIS SECURITY, BY ITS ACCEPTANCE HEREOF, AGREES TO OFFER,
SELL OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE "RESALE
RESTRICTION TERMINATION DATE") WHICH IS TWO YEARS AFTER THE LATER OF THE
ORIGINAL ISSUE DATE HEREOF AND THE LAST DATE ON WHICH AFFILIATED MANAGERS GROUP,
INC. (THE "COMPANY" OR THE "ISSUER") OR ANY AFFILIATE OF THE COMPANY WAS THE
OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF SUCH SECURITY) ONLY (A) TO THE
COMPANY OR ANY SUBSIDIARY THEREOF, (B) FOR SO LONG AS THIS SECURITY AND THE
SHARES OF COMMON STOCK ISSUABLE UPON CONVERSION OF THIS SECURITY ARE ELIGIBLE
FOR RESALE PURSUANT TO RULE 144A, TO A PERSON IT REASONABLY BELIEVES IS A
"QUALIFIED INSTITUTIONAL BUYER" AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT
THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED
INSTITUTIONAL BUYER TO WHICH NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN
RELIANCE ON RULE 144A, (C) TO AN INSTITUTIONAL "ACCREDITED INVESTOR" WITHIN THE
MEANING OF SUBPARAGRAPH (A)(1), (2),(3) OR (7) OF RULE 501 UNDER THE SECURITIES
ACT THAT IS ACQUIRING THE SECURITY FOR ITS OWN ACCOUNT, OR FOR THE ACCOUNT OF
SUCH AN INSTITUTIONAL "ACCREDITED INVESTOR," FOR INVESTMENT PURPOSES AND NOT
WITH A VIEW TO, OR FOR OFFER OR SALE IN CONNECTION WITH, ANY DISTRIBUTION IN
VIOLATION OF THE SECURITIES ACT, (D) PURSUANT TO A REGISTRATION STATEMENT WHICH
HAS BEEN DECLARED


                                     A-2-1
<PAGE>

EFFECTIVE UNDER THE SECURITIES ACT, (E) IN AN OFFSHORE TRANSACTION IN ACCORDANCE
WITH RULE 904 OF REGULATION S UNDER THE SECURITIES ACT OR (F) PURSUANT TO
ANOTHER AVAILABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES
ACT, SUBJECT TO THE COMPANY'S AND THE TRUSTEE'S RIGHTS PRIOR TO ANY SUCH OFFER,
SALE OR TRANSFER, PURSUANT TO CLAUSE (C), (E) OR (F) TO REQUIRE THE DELIVERY OF
AN OPINION OF COUNSEL, CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO
EACH OF THEM, AND IN EACH OF THE FOREGOING CASES, A CERTIFICATE OF TRANSFER IN
THE FORM APPEARING ON THE OTHER SIDE OF THIS SECURITY IS COMPLETED AND DELIVERED
BY THE TRANSFEROR TO THE TRUSTEE. THIS LEGEND WILL BE REMOVED UPON THE REQUEST
OF THE HOLDER AFTER THE RESALE RESTRICTION TERMINATION DATE.

      [THE FOREGOING LEGEND MAY BE REMOVED FROM THIS SECURITY ON SATISFACTION OF
THE CONDITIONS SPECIFIED IN THE INDENTURE.]


                                     A-2-2
<PAGE>

                         AFFILIATED MANAGERS GROUP, INC.
                      Liquid Yield Option(TM) Note due 2021
                              (Zero Coupon-Senior)

No. C-                                   CUSIP:  008252AA6
Issue Date:  May 7, 2001                 Original Issue Discount: $95.05 (for
Issue Price:  $904.95                    each $1,000 Principal Amount at
(for each $1,000 Principal Amount at     Maturity)
Maturity)

      AFFILIATED MANAGERS GROUP, INC., a Delaware corporation, promises to pay
to CEDE & Co., or registered assigns, the Principal Amount at Maturity of ONE
HUNDRED NINETY FIVE MILLION DOLLARS ($195,000,000) on May 7, 2021.

      This Security shall not bear interest except as specified on the other
side of this Security. Original Issue Discount will accrue as specified on the
other side of this Security. This Security is convertible as specified on the
other side of this Security.

      Additional provisions of this Security are set forth on the other side of
this Security.

Dated: May 7, 2001                      AFFILIATED MANAGERS GROUP, INC.

                                        By ________________________________
                                           Name:
                                           Title:
Attest:

___________________________________
Name:
Title:

TRUSTEE'S CERTIFICATE OF
  AUTHENTICATION

FIRST UNION NATIONAL BANK, as Trustee,
certifies that this is one of the
Securities referred to in the within-
mentioned Indenture.


By _______________________________
   Authorized Signatory

Dated: ___________________________


                                     A-2-3
<PAGE>

                         [FORM OF REVERSE SIDE OF LYON]

                      Liquid Yield Option(TM) Note Due 2021
                              (Zero Coupon-Senior)

1. Interest.

      This Security shall not bear interest, except as specified in this
paragraph or in paragraph 10 hereof. If the Principal Amount at Maturity hereof
or any portion of such Principal Amount at Maturity is not paid when due
(whether upon acceleration pursuant to Section 6.02 of the Indenture, upon the
date set for payment of the Redemption Price pursuant to paragraph 5 hereof,
upon the date set for payment of the Purchase Price or Change in Control
Purchase Price pursuant to paragraph 6 hereof or upon the Stated Maturity of
this Security) (or if interest due hereon or any portion of such interest is not
paid when due in accordance with paragraph 10 hereof), then in each such case
the overdue amount shall, to the extent permitted by law, bear interest at the
rate of 0.50% per annum, compounded semi-annually, which interest shall accrue
from the date such overdue amount was originally due to the date payment of such
amount, including interest thereon, has been made or duly provided for. All such
interest shall be payable on demand. The accrual of such interest on overdue
amounts shall be in lieu of, and not in addition to, the continued accrual of
Original Issue Discount.

      Original Issue Discount (the difference between the Issue Price and the
Principal Amount at Maturity of the Security), in the period during which a
Security remains outstanding, shall accrue at 0.50% per annum, on a semiannual
bond equivalent basis using a 360-day year comprised of twelve 30-day months,
from the Issue Date of this Security.

2. Method of Payment.

      Subject to the terms and conditions of the Indenture, the Company will
make payments in respect of Redemption Price, Purchase Price, Change in Control
Purchase Price, Restated Principal Amount and at Stated Maturity to Holders who
surrender Securities to a Paying Agent to collect such payments in respect of
the Securities. The Company will pay cash amounts in money of the United States
that at the time of payment is legal tender for payment of public and private
debts. However, the Company may make such cash payments by check payable in such
money; provided that payment by wire transfer of immediately available funds
will be required with respect to principal of and interest, if any, on all
Global Securities and all other Securities the Holders of which shall have
provided wire transfer instructions to the Company or the Paying Agent. Any
payment required to be made on any day that is not a Business Day will be made
on the next succeeding Business Day.

3. Paying Agent, Conversion Agent and Registrar.

      Initially, First Union National Bank, a national banking association (the
"Trustee"), will act as Paying Agent, Conversion Agent and Registrar. The
Company may appoint and change

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


                                     A-2-4
<PAGE>

any Paying Agent, Conversion Agent, Registrar or co-registrar without notice,
other than notice to the Trustee except that the Company will maintain at least
one Paying Agent in the State of New York, City of New York, Borough of
Manhattan, which shall initially be an office or agency of the Trustee. The
Company or any of its Subsidiaries or any of their Affiliates may act as Paying
Agent, Conversion Agent, Registrar or co-registrar.

4. Indenture.

      The Company issued the Securities under an Indenture dated as of May 7,
2001 (the "Indenture"), between the Company and the Trustee. The terms of the
Securities include those stated in the Indenture and those made part of the
Indenture by reference to the Trust Indenture Act of 1939, as in effect from
time to time (the "TIA"). Capitalized terms used herein and not defined herein
have the meanings ascribed thereto in the Indenture. The Securities are subject
to all such terms, and Securityholders are referred to the Indenture and the TIA
for a statement of those terms.

      The Securities are general unsecured obligations of the Company limited to
$195,000,000 aggregate Principal Amount at Maturity (subject to Sections 2.02
and 2.07 of the Indenture). The Indenture does not limit other indebtedness of
the Company, secured or unsecured.

5. Redemption at the Option of the Company.

      No sinking fund is provided for the Securities. The Securities are
redeemable as a whole, or from time to time in part, at any time at the option
of the Company at the Redemption Prices set forth below, provided that the
Securities are not redeemable prior to May 7, 2006.

      The table below shows Redemption Prices of a Security per $1,000 Principal
Amount at Maturity on the dates shown below and at Stated Maturity, which prices
reflect accrued Original Issue Discount calculated to each such date. The
Redemption Price of a Security redeemed between such dates shall include an
additional amount reflecting the additional Original Issue Discount accrued
since the preceding date in the table through the date of redemption.

                                                        (2)
                                         (1)          ORIGINAL         (3)
                                         LYON          ISSUE        REDEMPTION
                                        ISSUE       DISCOUNT AT       PRICE
REDEMPTION DATE                         PRICE           0.5%        (1) + (2)
---------------------------------      -------      -----------     ----------

May 7, 2006......................      $904.95         $22.88        $927.83
May 7, 2007......................      $904.95         $27.52        $932.47
May 7, 2008......................      $904.95         $32.19        $937.14
May 7, 2009......................      $904.95         $36.88        $941.83
May 7, 2010......................      $904.95         $41.60        $946.55
May 7, 2011......................      $904.95         $46.34        $951.29
May 7, 2012......................      $904.95         $51.10        $956.05
May 7, 2013......................      $904.95         $55.89        $960.84
May 7, 2014......................      $904.95         $60.70        $965.65


                                     A-2-5
<PAGE>

                                                        (2)
                                         (1)          ORIGINAL         (3)
                                         LYON          ISSUE        REDEMPTION
                                        ISSUE       DISCOUNT AT       PRICE
REDEMPTION DATE                         PRICE           0.5%        (1) + (2)
---------------------------------      -------      -----------     ----------

May 7, 2015......................      $904.95         $65.53        $970.48
May 7, 2016......................      $904.95         $70.39        $975.34
May 7, 2017......................      $904.95         $75.27        $980.22
May 7, 2018......................      $904.95         $80.18        $985.13
May 7, 2019......................      $904.95         $85.11        $990.06
May 7, 2020......................      $904.95         $90.07        $995.02
At stated maturity...............      $904.95         $95.05      $1,000.00

If converted to a semiannual coupon note following the occurrence of a Tax
Event, this Security will be redeemable at a Redemption Price equal to the
Restated Principal Amount plus accrued and unpaid interest from the date of such
conversion through the Redemption Date; but in no event will this Security be
redeemable before May 7, 2006.

6. Purchase By the Company at the Option of the Holder.

      Subject to the terms and conditions of the Indenture, the Company shall
become obligated to purchase, at the option of the Holder, the Securities held
by such Holder on the following Purchase Dates and at the following Purchase
Prices per $1,000 Principal Amount at Maturity, upon delivery of a Purchase
Notice containing the information set forth in the Indenture, at any time from
the opening of business on the date that is 30 Business Days prior to such
Purchase Date until the close of business on such Purchase Date and upon
delivery of the Securities to the Paying Agent by the Holder as set forth in the
Indenture.

                   Purchase Date        Purchase Price
                   -------------        --------------
                    May 7, 2002            $909.48
                    May 7, 2004            $918.61
                    May 7, 2006            $927.83
                    May 7, 2011            $951.29
                    May 7, 2016            $975.34

      The Purchase Price (equal to the Issue Price plus accrued Original Issue
Discount to the Purchase Date) may be paid, at the option of the Company, in
cash or by the issuance and delivery of shares of Common Stock of the Company,
or in any combination thereof.

      If prior to a Purchase Date this Security has been converted to a
semiannual coupon note following the occurrence of a Tax Event, the Purchase
Price will be equal to the Restated Principal Amount plus accrued and unpaid
interest from the date of conversion to the Purchase Date.

      At the option of the Holder and subject to the terms and conditions of the
Indenture, the Company shall become obligated to purchase the Securities held by
such Holder as of the date


                                     A-2-6
<PAGE>

that is 35 Business Days after the occurrence of a Change in Control of the
Company occurring on or prior to May 7, 2006 for a Change in Control Purchase
Price equal to the Issue Price plus accrued Original Issue Discount to the
Change in Control Purchase Date, which Change in Control Purchase Price shall be
paid in cash.

      If prior to a Change in Control Purchase Date this Security has been
converted to a semiannual coupon note following the occurrence of a Tax Event,
the Change in Control Purchase Price shall be equal to the Restated Principal
Amount plus accrued and unpaid interest from the date of conversion to the
Change in Control Purchase Date.

      Holders have the right to withdraw any Purchase Notice or Change in
Control Purchase Notice, as the case may be, by delivering to the Paying Agent a
written notice of withdrawal in accordance with the provisions of the Indenture.

      If cash (and/or securities if permitted under the Indenture) sufficient to
pay the Purchase Price or Change in Control Purchase Price, as the case may be,
of all Securities or portions thereof to be purchased as of the Purchase Date or
the Change in Control Purchase Date, as the case may be, is deposited with the
Paying Agent on the Business Day following the Purchase Date or the Change in
Control Purchase Date, as the case may be, Original Issue Discount ceases to
accrue on such Securities (or portions thereof) immediately after such Purchase
Date or Change in Control Purchase Date, as the case may be, and the Holder
thereof shall have no other rights as such (other than the right to receive the
Purchase Price or Change in Control Purchase Price, as the case may be, upon
surrender of such Security).

7. Notice of Redemption.

      Notice of redemption will be mailed at least 15 days but not more than 60
days before the Redemption Date to each Holder of Securities to be redeemed at
the Holder's registered address. If money sufficient to pay the Redemption Price
of all Securities (or portions thereof) to be redeemed on the Redemption Date is
deposited with the Paying Agent prior to or on the Redemption Date, immediately
after such Redemption Date Original Issue Discount ceases to accrue on such
Securities or portions thereof. Securities in denominations larger than $1,000
of Principal Amount at Maturity may be redeemed in part but only in integral
multiples of $1,000 of Principal Amount at Maturity.

8. Conversion.

      (a) Conversion Based on Common Stock Price. Subject to the provisions of
this paragraph 8 and notwithstanding the fact that any other condition to
conversion has not been satisfied, Holders may convert the Securities into
Common Stock on a Conversion Date in any fiscal quarter commencing after June
30, 2001, if, as of the last day of the preceding fiscal quarter, the Sale Price
of the Common Stock for at least 20 trading days in a period of 30 consecutive
trading days ending on the last trading day of such preceding fiscal quarter is
greater than the conversion trigger price. The "conversion trigger price" for
any fiscal quarter shall be a reference percentage, beginning at 120%, and
declining 0.12658% per quarter thereafter until it reaches 110.00018% for the
quarter beginning April 1, 2021, of the accreted conversion price per share of
Common Stock on the last trading day of such preceding calendar quarter.


                                     A-2-7
<PAGE>

      The "accreted conversion price" per share of Common Stock as of any day
equals the quotient of:

            o     the Issue Price and accrued Original Issue Discount to that
                  day, divided by

            o     the number of shares of Common Stock issuable upon conversion
                  of $1,000 Principal Amount at Maturity of Securities on that
                  day.

      For illustrative purposes only, the table below shows the conversion
trigger price per share of Common Stock in respect of each of the first 20
fiscal quarters following issuance of the Securities. The conversion trigger
price for any fiscal quarter starting on or after June 30, 2001 shall be the
conversion trigger price as of the last day of the immediately preceding fiscal
quarter as set forth in the table below. These conversion trigger prices reflect
the accreted conversion price per share of Common Stock (assuming that no events
occurred requiring an adjustment to the initial Conversion Rate of 11.6195
shares of Common Stock per $1,000 Principal Amount of Maturity) multiplied by
the applicable percentage for the respective fiscal quarter. Thereafter, the
accreted conversion price per share of Common Stock increases each fiscal
quarter by the accrued Original Issue Discount for the quarter and the
applicable percentage declines by 0.12658% per quarter. The conversion trigger
price for the calendar quarter beginning April 1, 2021 is $94.62.

                                          (1)            (2)            (3)
                                        Accreted                    Conversion
                                       Conversion     Applicable   Trigger Price
Calendar Quarter                         Price        Percentage     (1) X (2)
----------------                         -----        ----------     ---------

2001
   Quarter ended September 30, 2001      77.94        120.00000%      $93.53
   Quarter ended December 31, 2001       78.04        119.87342%      $93.55
2002
   Quarter ended March 31, 2002          78.14        119.74684%      $93.56
   Quarter ended June 30, 2002           78.23        119.62026%      $93.58
   Quarter ended September 30, 2002      78.33        119.49368%      $93.60
   Quarter ended December 31, 2002       78.43        119.36710%      $93.62
2003
   Quarter ended March 31, 2003          78.53        119.24052%      $93.64
   Quarter ended June 30, 2003           78.62        119.11394%      $93.65
   Quarter ended September 30, 2003      78.72        118.98736%      $93.67
   Quarter ended December 31, 2003       78.82        118.86078%      $93.69
2004
   Quarter ended March 31, 2004          78.92        118.73420%      $93.70
   Quarter ended June 30, 2004           79.02        118.60762%      $93.72
   Quarter ended September 30, 2004      79.12        118.48104%      $93.74
   Quarter ended December 31, 2004       79.22        118.35446%      $93.76
2005
   Quarter ended March 31, 2005          79.31        118.22788%      $93.77
   Quarter ended June 30, 2005           79.41        118.10130%      $93.79
   Quarter ended September 30, 2005      79.51        117.97472%      $93.81
   Quarter ended December 31, 2005       79.61        117.84814%      $93.82
2006
   Quarter ended March 31, 2006          79.71        117.72156%      $93.84
   Quarter ended June 30, 2006           79.81        117.59498%      $93.85

--------------------
*     This table assumes no events occurred that would require an adjustment to
      the conversion rate.


                                     A-2-8
<PAGE>

      (b) Conversion Based on Credit Rating. Subject to the provisions of
this paragraph 8 and notwithstanding the fact any other condition to
conversion has not been satisfied, Holders may convert the Securities into
Common Stock on a Conversion Date during any period in which the credit
rating assigned to the Securities by Standard & Poor's Ratings Services, a
division of The McGraw-Hill Companies Inc., and its successors ("Standard &
Poor's") or if Standard & Poor's is not making ratings of the Securities
publicly available, a nationally recognized U.S. rating agency or agencies,
as the case may be, selected by the Company, which will be substituted for
Standard & Poor's, is below the Applicable Rating. "Applicable Rating" means,
(1) BB-, in the case of Standard & Poor's (or its equivalent, under any
successor ratings categories of Standard & Poor's) or (2) the equivalent in
respect of ratings categories of any rating agencies substituted for Standard
& Poor's.

      (c) Conversion Based on Redemption. Subject to the provisions of this
paragraph 8 and notwithstanding the fact that any other condition to conversion
has not been satisfied, a Holder may convert into Common Stock a Security or
portion of a Security which has been called for redemption pursuant to paragraph
6 hereof, even if the foregoing provisions have not been satisfied, but such
Securities may be surrendered for conversion until the close of business on the
second Business Day immediately preceding the Redemption Date.

      (d) Conversion Upon Occurrence of Certain Corporate Transactions. Subject
to the provisions of this paragraph 8 and notwithstanding the fact that any
other condition to conversion has not been satisfied, in the event that the
Company declares a dividend or distribution described in Section 11.07 of the
Indenture, or a dividend or a distribution described in Section 11.08 of the
Indenture where the fair market value of such dividend or distribution per share
of Common Stock, as determined in the Indenture, exceeds 15% of the Sale Price
of the Common Stock on the Business Day immediately preceding the date of
declaration for such dividend or distribution, the Securities may be surrendered
for conversion beginning on the date the Company gives notice to the Holders of
such right, which shall not be less than 20 days prior to the Ex-Dividend Time
for such dividend or distribution, and Securities may be surrendered for
conversion at any time thereafter until the close of business on the Business
Day prior to the Ex-Dividend Time or until the Company announces that such
dividend or distribution will not take place.

      Subject to the provisions of this paragraph 8 and notwithstanding the fact
that any other condition to conversion has not been satisfied, in the event the
Company is a party to a consolidation, merger or binding share exchange or a
transfer of all or substantially all assets of the Company pursuant to which the
Common Stock would be converted into cash, securities or other property as set
forth in Section 11.14 of the Indenture, the Securities may be surrendered for
conversion at any time from and after the date which is 15 days prior to the
date the Company announces the anticipated effective time until 15 days after
the actual effective date of such transaction, and at the effective time of such
transaction the right to convert a Security into Common Stock will be deemed to
have changed into a right to convert it into the kind and amount of cash,
securities or other property which the holder would have received if the holder
had converted its Security immediately prior to the transaction.

      A Security in respect of which a Holder has delivered a Purchase Notice or
Change in Control Purchase Notice exercising the option of such Holder to
require the Company to


                                     A-2-9
<PAGE>

purchase such Security may be converted only if such notice of exercise is
withdrawn in accordance with the terms of the Indenture.

      The initial Conversion Rate is 11.6195 shares of Common Stock per $1,000
Principal Amount at Maturity, subject to adjustment in certain events described
in the Indenture. The Company will deliver cash or a check in lieu of any
fractional share of Common Stock.

      In the event the Company exercises its option pursuant to Section 10.01 of
the Indenture to have interest in lieu of Original Issue Discount accrue on the
Security following a Tax Event, the Holder will be entitled on conversion to
receive the same number of shares of Common Stock such Holder would have
received if the Company had not exercised such option. Accrued and unpaid
interest in lieu of Original Issue Discount will not be paid on Securities that
are converted; provided, however, that Securities surrendered for conversion
during the period, in the case of interest in lieu of Original Issue Discount,
from the close of business on any Regular Record Date next preceding any
Interest Payment Date to the opening of business on such Interest Payment Date
shall be entitled to receive such interest, in lieu of Original Issue Discount,
payable on such Securities on the corresponding Interest Payment Date and
(except Securities with respect to which the Company has mailed a notice of
redemption) Securities surrendered for conversion during such periods must be
accompanied by payment of an amount equal to the interest in lieu of Original
Issue Discount with respect thereto that the registered Holder is to receive.

      To convert a Security, a Holder must (1) complete and manually sign the
conversion notice below (or complete and manually sign a facsimile of such
notice) and deliver such notice to the Conversion Agent, (2) surrender the
Security to the Conversion Agent, (3) furnish appropriate endorsements and
transfer documents if required by the Conversion Agent, the Company or the
Trustee and (4) pay any transfer or similar tax, if required.

      A Holder may convert a portion of a Security if the Principal Amount at
Maturity of such portion is $1,000 or an integral multiple of $1,000. No payment
or adjustment will be made for dividends on the Common Stock except as provided
in the Indenture. On conversion of a Security, that portion of accrued Original
Issue Discount (or interest if the Company has exercised its option provided for
in paragraph 10 hereof) attributable to the period from the Issue Date (or, if
the Company has exercised the option referred to in paragraph 10 hereof, the
later of (x) the date of such exercise and (y) the date on which interest was
last paid) through the Conversion Date with respect to the converted Security
shall not be canceled, extinguished or forfeited, but rather shall be deemed to
be paid in full to the Holder thereof through the delivery of the Common Stock
(together with the cash payment, if any, in lieu of fractional shares) in
exchange for the Security being converted pursuant to the terms hereof; and the
fair market value of such shares of Common Stock (together with any such cash
payment in lieu of fractional shares) shall be treated as issued, to the extent
thereof, first in exchange for Original Issue Discount (or interest, if the
Company has exercised its option provided for in paragraph 10 hereof) accrued
through the Conversion Date, and the balance, if any, of such fair market value
of such Common Stock (and any such cash payment) shall be treated as issued in
exchange for the Issue Price of the Security being converted pursuant to the
provisions hereof.


                                     A-2-10
<PAGE>

      The Conversion Rate will be adjusted for dividends or distributions on
Common Stock payable in Common Stock or other Capital Stock; subdivisions,
combinations or certain reclassifications of Common Stock; distributions to all
holders of Common Stock of certain rights to purchase Common Stock for a period
expiring within 60 days at less than the Sale Price at the Time of
Determination; and distributions to such holders of assets or debt securities of
the Company or certain rights to purchase securities of the Company (excluding
certain cash dividends or distributions). However, no adjustment need be made if
Securityholders may participate in the transaction or in certain other cases.
The Company from time to time may voluntarily increase the Conversion Rate.

      If the Company is a party to a consolidation, merger or binding share
exchange or a transfer of all or substantially all of its assets, or upon
certain distributions described in the Indenture, the right to convert a
Security into Common Stock may be changed into a right to convert it into
securities, cash or other assets of the Company or another person.

9. Conversion Arrangement on Call for Redemption.

      Any Securities called for redemption, unless surrendered for conversion
before the close of business on the Redemption Date, may be deemed to be
purchased from the Holders of such Securities at an amount not less than the
Redemption Price, by one or more investment bankers or other purchasers who may
agree with the Company to purchase such Securities from the Holders, to convert
them into Common Stock of the Company and to make payment for such Securities to
the Trustee in trust for such Holders.

10. Tax Event

      (a) From and after the later of (i) the date (the "Tax Event Date") of the
occurrence of a Tax Event or (ii) the date the Company exercises such option
(the "Option Exercise Date"), at the option of the Company, interest in lieu of
future Original Issue Discount shall accrue at the rate of 0.50% per annum on a
principal amount per Security (the "Restated Principal Amount") equal to the
Issue Price plus Original Issue Discount accrued through the Option Exercise
Date and shall be payable semiannually on May 7 and November 7of each year (each
an "Interest Payment Date") to holders of record at the close of business on
April 21 or October 22 (each a "Regular Record Date") immediately preceding such
Interest Payment Date. Interest will be computed on the basis of a 360-day year
comprised of twelve 30-day months and will accrue from the most recent date to
which interest has been paid or, if no interest has been paid, from the Option
Exercise Date.

      (b) Interest on any Security that is payable, and is punctually paid or
duly provided for, on any Interest Payment Date shall be paid to the person in
whose name that Security is registered at the close of business on the Regular
Record Date for such interest at the office or agency of the Company maintained
for such purpose. Each installment of interest on any Security shall be paid by
check; provided that payment by wire transfer of immediately available funds
will be required with respect to principal on and interest, if any, on all
Global Securities and all other Securities the holders of which shall have
provided wire transfer instructions to the Company or the Paying Agent for an
account maintained by the payee located inside the United States.


                                     A-2-11
<PAGE>

      (c) Except as otherwise specified with respect to the Securities, any
Defaulted Interest on any Security shall forthwith cease to be payable to the
registered Holder thereof on the relevant Regular Record Date by virtue of
having been such Holder, and such Defaulted Interest may be paid by the Company
as provided for in Section 10.02(b) of the Indenture.

11. Denominations; Transfer; Exchange.

      The Securities are in fully registered form, without coupons, in
denominations of $1,000 of Principal Amount at Maturity and integral multiples
of $1,000. A Holder may transfer or exchange Securities in accordance with the
Indenture. The Registrar may require a Holder, among other things, to furnish
appropriate endorsements and transfer documents and to pay any taxes and fees
required by law or permitted by the Indenture. The Registrar need not transfer
or exchange any Securities selected for redemption (except, in the case of a
Security to be redeemed in part, the portion of the Security not to be redeemed)
or any Securities in respect of which a Purchase Notice or Change in Control
Purchase Notice has been given and not withdrawn (except, in the case of a
Security to be purchased in part, the portion of the Security not to be
purchased) or any Securities for a period of 15 days before the mailing of a
notice of redemption of Securities to be redeemed.

12. Persons Deemed Owners.

      The registered Holder of this Security may be treated as the owner of this
Security for all purposes.

13. Unclaimed Money or Securities.

      The Trustee and the Paying Agent shall return to the Company upon written
request any money or securities held by them for the payment of any amount with
respect to the Securities that remains unclaimed for two years subject to
applicable unclaimed property law. After return to the Company, Holders entitled
to the money or securities must look to the Company for payment as general
creditors unless an applicable abandoned property law designates another person.

14. Amendment; Waiver.

      Subject to certain exceptions set forth in the Indenture, (i) the
Indenture or the Securities may be amended with the written consent of the
Holders of at least a majority in aggregate Principal Amount at Maturity of the
Securities at the time outstanding and (ii) certain Defaults may be waived with
the written consent of the Holders of a majority in aggregate Principal Amount
at Maturity of the Securities at the time outstanding. Subject to certain
exceptions set forth in the Indenture, without the consent of any
Securityholder, the Company and the Trustee may amend the Indenture or the
Securities to cure any ambiguity, omission, defect or inconsistency, or to
comply with Article 5 or Section 11.14 of the Indenture, to provide for
uncertificated Securities in addition to or in place of certificated Securities
or to make any change that does not adversely affect the rights of any
Securityholder, or to comply with any requirement of the SEC in connection with
the qualification of the Indenture under the TIA.


                                     A-2-12
<PAGE>50

15. Defaults and Remedies.

      Under the Indenture, Events of Default include (i) if the Securities have
been converted to semiannual coupon notes following a Tax Event, default in the
payment of interest which default continues for a period of 30 days; (ii)
default in payment of the Principal Amount at Maturity (or, if the Securities
have been converted to semiannual coupon notes following a Tax Event, the
Restated Principal Amount), Issue Price plus accrued Original Issue Discount,
Redemption Price, Purchase Price or Change in Control Purchase Price, as the
case may be, in respect of the Securities when the same becomes due and payable;
(iii) failure by the Company to comply with other agreements in the Indenture or
the Securities, subject to notice and lapse of time; (iv) default under any
Debt, whether such Debt now exists or is created later, which default results in
such Debt becoming or being declared due and payable prior to the date on which
it would otherwise have become due and payable, and the principal amount of all
Debt so accelerated, together with all Debt due and payable but not paid prior
to the end of any grace period, is $30,000,000 or more, and such acceleration
has not been rescinded or annulled within a period of 30 days after receipt by
the Company of a Notice of Default, subject to notice and lapse of time;
provided, however, that if any such default shall be cured, waived, rescinded or
annulled, then the Event of Default by reason thereof shall be deemed not to
have occurred; (v) final unsatisfied judgments not covered by insurance
aggregating in excess of $30,000,000 rendered against the Company or the
Operating Company and not stayed, bonded or discharged within 60 days; and (vi)
certain events of bankruptcy or insolvency. If an Event of Default occurs and is
continuing, the Trustee, or the Holders of at least 25% in aggregate Principal
Amount at Maturity of the Securities at the time outstanding, may declare all
the Securities to be due and payable immediately. Certain events of bankruptcy
or insolvency are Events of Default which will result in the Securities becoming
due and payable immediately upon the occurrence of such Events of Default.

      Holders may not enforce the Indenture or the Securities except as provided
in the Indenture. The Trustee may refuse to enforce the Indenture or the
Securities unless it receives reasonable indemnity or security. Subject to
certain limitations, Holders of a majority in aggregate Principal Amount at
Maturity of the Securities at the time outstanding may direct the Trustee in its
exercise of any trust or power. The Trustee may withhold from Securityholders
notice of any continuing Default (except a Default in payment of amounts
specified in clause (i) or (ii) above) if it determines that withholding notice
is in their interests.

16. Trustee Dealings with the Company.

      Subject to certain limitations imposed by the TIA, the Trustee under the
Indenture, in its individual or any other capacity, may become the owner or
pledgee of Securities and may otherwise deal with and collect obligations owed
to it by the Company or its Affiliates and may otherwise deal with the Company
or its Affiliates with the same rights it would have if it were not Trustee.

17. No Recourse Against Others.

      A director, officer, employee or stockholder, as such, of the Company
shall not have any liability for any obligations of the Company under the
Securities or the Indenture or for any


                                     A-2-13
<PAGE>

claim based on, in respect of or by reason of such obligations or their
creation. By accepting a Security, each Securityholder waives and releases all
such liability. The waiver and release are part of the consideration for the
issue of the Securities.

18. Authentication

      This Security shall not be valid until an authorized signatory of the
Trustee manually signs the Trustee's Certificate of Authentication on the other
side of this Security.

19. Abbreviations.

      Customary abbreviations may be used in the name of a Securityholder or an
assignee, such as TEN COM (=tenants in common), TEN ENT (=tenants by the
entireties), JT TEN (=joint tenants with right of survivorship and not as
tenants in common), CUST (=custodian), and U/G/M/A (=Uniform Gift to Minors
Act).

20. GOVERNING LAW.

      THE LAWS OF THE STATE OF NEW YORK SHALL GOVERN THE INDENTURE AND THIS
SECURITY, WITHOUT REGARD TO PRINCIPLES OF CONFLICT OF LAWS.

                                   ----------

      The Company will furnish to any Securityholder upon written request and
without charge a copy of the Indenture.

            Affiliated Managers Group, Inc.
            Two International Place
            Boston, MA 02110
            Telephone No. (617) 747-3300
            Facsimile No. (617) 747-3380
            Attention:  Treasurer


                                     A-2-14
<PAGE>

            ASSIGNMENT FORM                         CONVERSION NOTICE

To assign this Security, fill in the     To convert this Security into Common
form below:                              Stock of the Company, check the box:|_|

I or we assign and transfer this         To convert only part of this Security,
Security to                              state the Principal Amount at Maturity
                                         to be converted (which must be $1,000
___________________________________      or an integral multiple of $1,000):
                                         $___________________________

___________________________________      If you want the stock certificate made
(Insert assignee's soc. sec. or          out in another person's name, fill in
         tax ID no.)                     the form below:

___________________________________
                                         ___________________________________
___________________________________
(Print or type assignee's name, address  ___________________________________
             and zip code)
                                         (Insert other person's soc. sec. or
and irrevocably appoint _____________    tax ID no.)
agent to transfer this Security on the   ___________________________________
books of the Company.  The agent may
substitute another to act for him.       ___________________________________
                                         (Print or type other person's name,
                                         address and zip code)

Date: ___________________________        Your
                                         Signature: ___________________________*
                                         (Sign exactly as your name appears on
                                         the other side of this Security)


* Your signature must be guaranteed by an "eligible guarantor institution"
meeting the requirements of the Trustee, which requirements include membership
or participation in the Security Transfer Agent Medallion Program ("STAMP") or
such other "signature guarantee program" as may be determined by the Trustee in
addition to, or in substitution for, STAMP, all in accordance with the
Securities Exchange Act of 1934, as amended.


                                     A-2-15
<PAGE>

                                   EXHIBIT B-1

                              TRANSFER CERTIFICATE

      In connection with any transfer of any of the Securities within the period
prior to the expiration of the holding period applicable to the sales thereof
under Rule 144(k) under the Securities Act of 1933, as amended (the "Securities
Act") (or any successor provision), the undersigned registered owner of this
Security hereby certifies with respect to $1,000 Principal Amount at Maturity of
the above-captioned securities presented or surrendered on the date hereof (the
"Surrendered Securities") for registration of transfer, or for exchange or
conversion where the securities issuable upon such exchange or conversion are to
be registered in a name other than that of the undersigned registered owner
(each such transaction being a "transfer"), that such transfer complies with the
restrictive legend set forth on the face of the Surrendered Securities for the
reason checked below:

            |_|   The transfer of the Surrendered Securities complies with Rule
                  144 under the U.S. Securities Act of 1933, as amended (the
                  "Securities Act"); or

            |_|   The transfer of the Surrendered Securities complies with Rule
                  144A under the Securities Act; or

            |_|   The transfer of the Surrendered Securities is to an
                  institutional accredited investor, as described in Rule
                  501(a)(1), (2), (3) or (7) of Regulation D under the
                  Securities Act; or

            |_|   The transfer of the Surrendered Securities is pursuant to an
                  effective registration statement under the Securities Act; or

            |_|   The transfer of the Surrendered Securities is in an offshore
                  transaction in accordance with Rule 904 of Regulation S under
                  the Securities Act; or

            |_|   The transfer of the Surrendered Securities is pursuant to
                  another available exemption from the registration requirements
                  of the Securities Act.

and unless the box below is checked, the undersigned confirms that, to the
undersigned's knowledge, such Securities are not being transferred to an
"affiliate" of the Company as defined in Rule 144 under the Securities Act (an
"Affiliate").

            |_|   The transferee is an Affiliate of the Company.

DATE: ___________________________


                                                  _____________________________*
                                                            Signature(s)


                                     B-1-1
<PAGE>

 (If the registered owner is a corporation, partnership or fiduciary, the title
    of the Person signing on behalf of such registered owner must be stated.)

* Your signature must be guaranteed by an "eligible guarantor institution"
meeting the requirements of the Trustee, which requirements include membership
or participation in the Security Transfer Agent Medallion Program ("STAMP") or
such other "signature guarantee program" as may be determined by the Trustee in
addition to, or in substitution for, STAMP, all in accordance with the
Securities Exchange Act of 1934, as amended.


                                     B-1-2
<PAGE>

                                   EXHIBIT B-2

             Form of Letter to be Delivered by Accredited Investors

Affiliated Managers Group, Inc.
Two International Place
Boston, MA 02110
Telephone No. (617) 747-3300
Facsimile No. (617) 747-3380

First Union National Bank
One World Trade Center
Suite 4711
New York, NY 10048
Telephone No. (212) 938-0779
Facsimile No. (212) 938-0821
Attention: Corporate Trust - Bond Administration

Dear Ladies/Gentlemen:

      We are delivering this letter in connection with the proposed transfer of
$_____________ Principal Amount at Maturity of the Liquid Yield Option Notes due
2021 ("LYONs") of Affiliated Managers Group, Inc. (the "Company"), which are
convertible into shares of the Company's Common Stock, $0.01 par value per share
(the "Common Stock").

      We hereby confirm that:

            (i) we are an "accredited investor" within the meaning of Rule
      501(a)(1), (2) or (3) under the Securities Act of 1933, as amended (the
      "Securities Act"), or an entity in which all of the equity owners are
      accredited investors within the meaning of Rule 501(a)(1), (2) or (3)
      under the Securities Act (an "Institutional Accredited Investor");

            (ii) (A) the purchase of LYONs by us is for our own account or for
      the account of one or more other Institutional Accredited Investors or as
      fiduciary for the account of one or more trusts, each of which is an
      "accredited investor" within the meaning of Rule 501(a)(7) under the
      Securities Act and for each of which we exercise sole investment
      discretion or (B) we are a "bank," within the meaning of Section 3(a)(2)
      of the Securities Act, or a "savings and loan association" or other
      institution described in Section 3(a)(5)(A) of the Securities Act that is
      acquiring LYONs as fiduciary for the account of one or more institutions
      for which we exercise sole investment discretion;

            (iii) we have such knowledge and experience in financial and
      business matters that we are capable of evaluating the merits and risks of
      purchasing LYONs; and

            (iv) we are not acquiring LYONs with a view to distribution thereof
      or with any present intention of offering or selling LYONs or the Common
      Stock issuable upon conversion thereof, except as permitted below;
      provided that the disposition of our


                                     B-2-1
<PAGE>

      property and property of any accounts for which we are acting as fiduciary
      shall remain at all times within our control.

      We understand that the LYONs were originally offered and sold in a
transaction not involving any public offering within the United States within
the meaning of the Securities Act and that the LYONs and the shares of Common
Stock (the "Securities") issuable upon conversion thereof have not been
registered under the Securities Act, and we agree, on our own behalf and on
behalf of each account for which we acquire any LYONs, that if in the future we
decide to resell or otherwise transfer such Securities prior to the date (the
"Resale Restriction Termination Date") which is two years after the later of the
original issuance of the LYONs and the last date on which the Company or an
affiliate of the Company was the owner of the Security, such Securities may be
resold or otherwise transferred only (i) to Affiliated Managers Group, Inc. or
any subsidiary thereof, or (ii) for as long as the LYONs are eligible for resale
pursuant to Rule 144A, to a person it reasonably believes is a "qualified
institutional buyer" (as defined in Rule 144A under the Securities Act) that
purchases for its own account or for the account of a qualified institutional
buyer to which notice is given that the transfer is being made in reliance on
Rule 144A, or (iii) to an Institutional Accredited Investor that is acquiring
the Security for its own account, or for the account of such an Institutional
Accredited Investor for investment purposes and not with a view to, or for offer
or sale in connection with, any distribution in violation of the Securities Act,
or (iv) pursuant to a registration statement which has been declared effective
under the Securities Act, or (v) in an offshore transaction in accordance with
Rule 904 of Regulation S under the Securities Act or (vi) pursuant to another
available exemption from registration under the Securities Act (if applicable)
and, in each case, in accordance with any applicable securities laws of any
State of the United States or any other applicable jurisdiction and in
accordance with the legends set forth on the Securities. We further agree to
provide any person purchasing any of the Securities other than pursuant to
clause (iv) above from us a notice advising such purchaser that resales of such
securities are restricted as stated herein. We understand that the trustee or
the transfer agent, as the case may be, for the Securities will not be required
to accept for registration of transfer any Securities pursuant to (iii), (v) or
(vi) above except upon presentation of evidence satisfactory to the Company and
the Trustee that the foregoing restrictions on transfer have been complied with.
We further understand that any Securities will be in the form of definitive
physical certificates and that such certificates will bear a legend reflecting
the substance of this paragraph other than certificates representing Securities
transferred pursuant to clause (iv) above.

      We acknowledge that the Company, others and you will rely upon our
confirmations, acknowledgments and agreements set forth herein, and we agree to
notify you promptly in writing if any of our representations or warranties
herein ceases to be accurate and complete.


                                     B-2-2
<PAGE>

      THIS LETTER SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE
INTERNAL LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO PRINCIPLES OF
CONFLICTS OF LAWS.

                               _______________________________________
                               (Name of Purchaser)


                               By: __________________________________ *
                                   Name:
                                   Title:
                                   Address:

* Your signature must be guaranteed by an "eligible guarantor institution"
meeting the requirements of the Trustee, which requirements include membership
or participation in the Security Transfer Agent Medallion Program ("STAMP") or
such other "signature guarantee program" as may be determined by the Trustee in
addition to, or in substitution for, STAMP, all in accordance with the
Securities Exchange Act of 1934, as amended.


                                     B-2-3