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                                                                    EXHIBIT 4.24


                                SUPPORT AGREEMENT

         MEMORANDUM OF AGREEMENT made as of the 1st day of August, 2000, between
AMVESCAP PLC a corporation existing under the laws of England (hereinafter
referred to as "AMVESCAP") and AVZ CALLCO INC., a company existing under the
laws of Nova Scotia (hereinafter referred to as "CALLCO") and AMVESCAP INC., a
corporation existing under the laws of Nova Scotia (hereinafter referred to as
"EXCHANGECO").

         RECITALS:

         (a)      In connection with an amended and restated merger agreement
                  (the "MERGER AGREEMENT") made as of May 9, 2000 among AMVESCAP
                  and Trimark Financial Corporation ("TRIMARK"), Exchangeco is
                  to issue exchangeable shares (the "EXCHANGEABLE SHARES") to
                  certain holders of securities of Trimark pursuant to the plan
                  of arrangement contemplated by the Merger Agreement;

         (b)      In connection with an indenture (the "INDENTURE") made as of
                  the date hereof among AMVESCAP, Exchangeco and CIBC Mellon
                  Trust Company, Exchangeco may issue Exchangeable Shares to
                  holders of 6% equity subordinated debentures of Exchangeco
                  (the "DEBENTURES") which may be issued to certain holders of
                  securities of Trimark pursuant to the plan of arrangement
                  contemplated by the Merger Agreement; and

         (c)      Pursuant to the Merger Agreement, AMVESCAP, Callco and
                  Exchangeco are required to execute a support agreement
                  substantially in the form of this agreement.

         In consideration of the foregoing and the mutual agreements contained
herein (the receipt and adequacy of which are acknowledged), the parties agree
as follows:

                                    ARTICLE 1
                         DEFINITIONS AND INTERPRETATION

SECTION 1.1 DEFINED TERMS

         Each term denoted herein by initial capital letters and not otherwise
defined herein shall have the meaning ascribed thereto in the rights,
privileges, restrictions and conditions (collectively, the "SHARE PROVISIONS")
attaching to the Exchangeable Shares as set out in the articles of Exchangeco,
unless the context requires otherwise.


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SECTION 1.2 INTERPRETATION NOT AFFECTED BY HEADINGS

         The division of this agreement into Articles, sections and other
portions and the insertion of headings are for convenience of reference only and
shall not affect the construction or interpretation of this agreement. Unless
otherwise indicated, all references to an "ARTICLE" or "SECTION" followed by a
number and/or a letter refer to the specified Article or Section of this
agreement. The terms "THIS AGREEMENT", "HEREOF", "HEREIN" and "HEREUNDER" and
similar expressions refer to this agreement and not to any particular Article,
section or other portion hereof and include any agreement or instrument
supplementary or ancillary hereto.

SECTION 1.3 NUMBER, GENDER

         Words importing the singular number only shall include the plural and
vice versa. Words importing any gender shall include all genders.

SECTION 1.4 DATE FOR ANY ACTION

         If any date on which any action is required to be taken under this
agreement is not a Business Day, such action shall be required to be taken on
the next succeeding Business Day. For the purposes of this agreement, a
"BUSINESS DAY" means any day on which commercial banks are open for business in
Toronto, Ontario and London, England, other than a Saturday, a Sunday or a day
observed as a holiday in Toronto, Ontario or London, England under applicable
laws.

                                    ARTICLE 2
                      COVENANTS OF AMVESCAP AND EXCHANGECO

SECTION 2.1 COVENANTS REGARDING EXCHANGEABLE SHARES

         So long as any Exchangeable Shares not owned by AMVESCAP or its
Affiliates are outstanding, AMVESCAP will:

         (a)      not declare or pay any dividend on the AMVESCAP Ordinary
                  Shares unless (i) Exchangeco shall on the same day declare or
                  pay, as the case may be, an equivalent dividend (as provided
                  for in the Share Provisions) on the Exchangeable Shares (an
                  "EQUIVALENT DIVIDEND") and (ii) Exchangeco shall have
                  sufficient money or other assets or authorized but unissued
                  securities available to enable the due declaration and the due
                  and punctual payment, in accordance with applicable law, of
                  any such Equivalent Dividend or (iii) Exchangeco shall (y)
                  subdivide the Exchangeable Shares in lieu of stock dividend
                  thereon (as provided for in the Share Provisions) (an
                  "EQUIVALENT STOCK SUBDIVISION"), and (z) have sufficient
                  authorized but unissued securities available to enable the
                  Equivalent Stock Subdivision;


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         (b)      advise Exchangeco sufficiently in advance of the declaration
                  by AMVESCAP of any dividend on AMVESCAP Ordinary Shares and
                  take all such other actions as are reasonably necessary, in
                  co-operation with Exchangeco, to ensure that (i) the
                  respective declaration date, record date and payment date for
                  an Equivalent Dividend on the Exchangeable Shares shall be the
                  same as the declaration date, record date and payment date for
                  the corresponding dividend on the AMVESCAP Ordinary Shares, or
                  (ii) the record date and effective date for an Equivalent
                  Stock Subdivision shall be the same as the record date and
                  payment date for the corresponding stock dividend on the
                  AMVESCAP Ordinary Shares;

         (c)      ensure that the record date for any dividend declared on
                  AMVESCAP Ordinary Shares is not less than 10 Business Days
                  after the declaration date of such dividend;

         (d)      take all such actions and do all such things as are reasonably
                  necessary or desirable to enable and permit Exchangeco, in
                  accordance with applicable law, to pay and otherwise perform
                  its obligations with respect to the satisfaction of the
                  Liquidation Amount, the Retraction Price or the Redemption
                  Price in respect of each issued and outstanding Exchangeable
                  Share (other than Exchangeable Shares owned by AMVESCAP or its
                  Affiliates) upon the liquidation, dissolution or winding-up of
                  Exchangeco or any other distribution of the assets of
                  Exchangeco among its shareholders for the purpose of winding
                  up its affairs, the delivery of a Retraction Request by a
                  holder of Exchangeable Shares or a redemption of Exchangeable
                  Shares by Exchangeco, as the case may be, including without
                  limitation all such actions and all such things as are
                  necessary or desirable to enable and permit Exchangeco to
                  cause to be delivered AMVESCAP Ordinary Shares to the holders
                  of Exchangeable Shares in accordance with the provisions of
                  Section 5, 6 or 7, as the case may be, of the Share
                  Provisions;

         (e)      take all such actions and do all such things as are reasonably
                  necessary or desirable to enable and permit Callco, in
                  accordance with applicable law, to perform its obligations
                  arising upon the exercise by it of the Liquidation Call Right,
                  the Retraction Call Right or the Redemption Call Right,
                  including without limitation all such actions and all such
                  things as are necessary or desirable to enable and permit
                  Callco to cause to be delivered AMVESCAP Ordinary Shares to
                  the holders of Exchangeable Shares in accordance with the
                  provisions of the Liquidation Call Right, the Retraction Call
                  Right or the Redemption Call Right, as the case may be; and


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         (f)      not exercise its vote as a shareholder to initiate the
                  voluntary liquidation, dissolution or winding up of Exchangeco
                  or any other distribution of the assets of Exchangeco among
                  its shareholders for the purpose of winding up its affairs,
                  nor take any action or omit to take any action that is
                  designed to result in the liquidation, dissolution or winding
                  up of Exchangeco or any other distribution of the assets of
                  Exchangeco among its shareholders for the purpose of winding
                  up its affairs.

SECTION 2.2 SEGREGATION OF FUNDS

         AMVESCAP will cause Exchangeco to deposit a sufficient amount of funds
in a separate account of Exchangeco and segregate a sufficient amount of such
other assets and property as is necessary to enable Exchangeco to pay dividends
when due and to pay or otherwise satisfy its respective obligations under
Sections 5, 6 and 7 of the Share Provisions, as applicable.

SECTION 2.3 RESERVATION OF AMVESCAP ORDINARY SHARES

         AMVESCAP hereby represents, warrants and covenants in favour of
Exchangeco and Callco that AMVESCAP has reserved for issuance and will, at all
times while any Exchangeable Shares or Debentures (other than Exchangeable
Shares or Debentures held by AMVESCAP or its Affiliates) are outstanding, keep
available, free from pre-emptive and other rights, out of its authorized and
unissued capital stock such number of AMVESCAP Ordinary Shares (or other shares
or securities into which AMVESCAP Ordinary Shares may be reclassified or changed
as contemplated by Section 2.7): (a) as is equal to the sum of (i) the number of
Exchangeable Shares issued and outstanding from time to time and (ii) the number
of Exchangeable Shares issuable upon the exercise of all rights to acquire
Exchangeable Shares outstanding from time to time, including such rights under
the terms of the Indenture; and (b) as are now and may hereafter be required to
enable and permit AMVESCAP to meet its obligations under the Voting and Exchange
Trust Agreement and under any other security or commitment pursuant to which
AMVESCAP may now or hereafter be required to issue AMVESCAP Ordinary Shares, to
enable and permit Callco to meet its obligations under each of the Liquidation
Call Right, the Retraction Call Right and the Redemption Call Right and to
enable and permit Exchangeco to meet its obligations hereunder and under the
Share Provisions.

SECTION 2.4 NOTIFICATION OF CERTAIN EVENTS

         In order to assist AMVESCAP to comply with its obligations hereunder
and to permit Callco to exercise the Liquidation Call Right, the Retraction Call
Right and the Redemption Call Right, Exchangeco will notify AMVESCAP and Callco
of each of the following events at the time set forth below:


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         (a)      in the event of any determination by the Board of Directors of
                  Exchangeco to institute voluntary liquidation, dissolution or
                  winding-up proceedings with respect to Exchangeco or to effect
                  any other distribution of the assets of Exchangeco among its
                  shareholders for the purpose of winding up its affairs, at
                  least 60 days prior to the proposed effective date of such
                  liquidation, dissolution, winding-up or other distribution;

         (b)      promptly, upon the earlier of receipt by Exchangeco of notice
                  of and Exchangeco otherwise becoming aware of any threatened
                  or instituted claim, suit, petition or other proceedings with
                  respect to the involuntary liquidation, dissolution or
                  winding-up of Exchangeco or to effect any other distribution
                  of the assets of Exchangeco among its shareholders for the
                  purpose of winding up its affairs;

         (c)      immediately, upon receipt by Exchangeco of a Retraction
                  Request;

         (d)      on the same date on which notice of redemption is given to
                  holders of Exchangeable Shares, upon the determination of a
                  Redemption Date in accordance with the Share Provisions; and

         (e)      as soon as practicable upon the issuance by Exchangeco of any
                  Exchangeable Shares or rights to acquire Exchangeable Shares
                  (other than the issuance of Exchangeable Shares and rights to
                  acquire Exchangeable Shares in exchange for Trimark Common
                  Shares pursuant to the Arrangement).

SECTION 2.5 DELIVERY OF AMVESCAP ORDINARY SHARES TO EXCHANGECO AND CALLCO

         In furtherance of its obligations under Section 2.1(d) and Section
2.1(e), upon notice from Exchangeco or Callco of any event that requires
Exchangeco or Callco to cause to be delivered AMVESCAP Ordinary Shares to any
holder of Exchangeable Shares, AMVESCAP shall forthwith allot, issue and deliver
or cause to be delivered to the relevant holder of Exchangeable Shares as
directed by Exchangeco or Callco the requisite number of AMVESCAP Ordinary
Shares to be allotted to, received by, and issued to or to the order of, the
former holder of the surrendered Exchangeable Shares (but, for the avoidance of
doubt, not to Exchangeco or Callco). All such AMVESCAP Ordinary Shares shall be
duly authorized and validly issued as fully paid and shall be free and clear of
any lien, claim or encumbrance. In consideration of the issuance and delivery of
each such AMVESCAP Ordinary Share, Exchangeco or Callco, as the case may be,
shall subscribe a cash amount or pay a purchase price equal to the fair market
value of such AMVESCAP Ordinary Shares.


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SECTION 2.6 QUALIFICATION OF AMVESCAP ORDINARY SHARES

         If any AMVESCAP Ordinary Shares (or other shares or securities into
which AMVESCAP Ordinary Shares may be reclassified or changed as contemplated by
Section 2.7) to be issued and delivered hereunder require registration or
qualification with or approval of or the filing of any document, including any
prospectus or similar document or the taking of any proceeding with or the
obtaining of any order, ruling or consent from any governmental or regulatory
authority under any United Kingdom or Canadian federal, provincial or
territorial securities or other law or regulation or pursuant to the rules and
regulations of any securities or other regulatory authority in the United
Kingdom or Canada or the fulfillment of any other United Kingdom or Canadian
legal requirement before such shares (or such other shares or securities) may be
issued by AMVESCAP and delivered by AMVESCAP at the direction of Callco or
Exchangeco, if applicable, to the holder of surrendered Exchangeable Shares or
in order that such shares (or such other shares or securities) may be freely
traded thereafter (other than any restrictions of general application on
transfer by reason of a holder being a "control person" for purposes of Canadian
federal, provincial or territorial securities law or the equivalent thereof
under any United Kingdom laws, rules, regulations or stock exchange
requirements), AMVESCAP will in good faith expeditiously take all such actions
and do all such things as are reasonably necessary or desirable to cause such
AMVESCAP Ordinary Shares (or such other shares or securities) to be and remain
duly registered, qualified or approved under United Kingdom and/or Canadian law.
AMVESCAP will in good faith expeditiously take all such actions and do all such
things as are reasonably necessary or desirable to cause all AMVESCAP Ordinary
Shares (or such other shares or securities) to be delivered hereunder to be
listed, quoted or posted for trading on all stock exchanges and quotation
systems on which outstanding AMVESCAP Ordinary Shares (or such other shares or
securities) have been listed by AMVESCAP and remain listed and are quoted or
posted for trading at such time, including, if required by the LSE or UKLA, by
preparing, filing and seeking approval for listing particulars for AMVESCAP
Ordinary Shares when Exchangeable Shares representing in excess of 9.9% of the
then outstanding AMVESCAP Ordinary Shares have been exchanged for AMVESCAP
Ordinary Shares, and thereafter, if required by the LSE or UKLA, on each
occasion when, during the period following the then most recent UKLA approval
for listing of AMVESCAP Ordinary Shares in respect of Exchangeable Shares,
additional Exchangeable Shares representing in excess of 9.9% of the then
outstanding AMVESCAP Ordinary Shares have been exchanged for AMVESCAP Ordinary
Shares.

SECTION 2.7 ECONOMIC EQUIVALENCE

         So long as any Exchangeable Shares not owned by AMVESCAP or its
Affiliates are outstanding:


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         (a)      AMVESCAP will not without prior approval of Exchangeco and the
                  prior approval of the holders of the Exchangeable Shares given
                  in accordance with section 10(2) of the Share Provisions:

                  (i)      issue or distribute AMVESCAP Ordinary Shares (or
                           securities exchangeable for or convertible into or
                           carrying rights to acquire AMVESCAP Ordinary Shares)
                           to the holders of all or substantially all of the
                           then outstanding AMVESCAP Ordinary Shares by way of
                           stock dividend or other distribution, other than an
                           issue of AMVESCAP Ordinary Shares (or securities
                           exchangeable for or convertible into or carrying
                           rights to acquire AMVESCAP Ordinary Shares) to
                           holders of AMVESCAP Ordinary Shares (i) who exercise
                           an option to receive dividends in AMVESCAP Ordinary
                           Shares (or securities exchangeable for or convertible
                           into or carrying rights to acquire AMVESCAP Ordinary
                           Shares) in lieu of receiving cash dividends, or (ii)
                           pursuant to any dividend reinvestment plan or scrip
                           dividend; or

                  (ii)     issue or distribute rights, options or warrants to
                           the holders of all or substantially all of the then
                           outstanding AMVESCAP Ordinary Shares entitling them
                           to subscribe for or to purchase AMVESCAP Ordinary
                           Shares (or securities exchangeable for or convertible
                           into or carrying rights to acquire AMVESCAP Ordinary
                           Shares); or

                  (iii)    issue or distribute to the holders of all or
                           substantially all of the then outstanding AMVESCAP
                           Ordinary Shares (A) shares or securities of AMVESCAP
                           of any class other than AMVESCAP Ordinary Shares
                           (other than shares convertible into or exchangeable
                           for or carrying rights to acquire AMVESCAP Ordinary
                           Shares), (B) rights, options or warrants other than
                           those referred to in Section 2.7(a)(ii), (C)
                           evidences of indebtedness of AMVESCAP or (D) assets
                           of AMVESCAP;

                  unless in each case the economic equivalent on a per share
                  basis of such rights, options, securities, shares, evidences
                  of indebtedness or other assets is issued or distributed
                  simultaneously to holders of the Exchangeable Shares; provided
                  that, for greater certainty, the above restrictions shall not
                  apply to any securities issued or distributed by AMVESCAP in
                  order to give effect to and to consummate the transactions
                  contemplated by, and in accordance with, the Merger Agreement.


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         (b)      AMVESCAP will not without the prior approval of Exchangeco and
                  the prior approval of the holders of the Exchangeable Shares
                  given in accordance with section 10(2) of the Share
                  Provisions:

                  (i)      subdivide, redivide or change the then outstanding
                           AMVESCAP Ordinary Shares into a greater number of
                           AMVESCAP Ordinary Shares; or

                  (ii)     reduce, combine, consolidate or change the then
                           outstanding AMVESCAP Ordinary Shares into a lesser
                           number of AMVESCAP Ordinary Shares; or

                  (iii)    reclassify or otherwise change AMVESCAP Ordinary
                           Shares or effect an amalgamation, merger,
                           reorganization or other transaction affecting
                           AMVESCAP Ordinary Shares;

                  unless the same or an economically equivalent change shall
                  simultaneously be made to, or in the rights of the holders of,
                  the Exchangeable Shares.

         (c)      AMVESCAP will ensure that the record date for any event
                  referred to in Section 2.7(a) or Section 2.7(b), or (if no
                  record date is applicable for such event) the effective date
                  for any such event, is not less than five Business Days after
                  the date on which such event is declared or announced by
                  AMVESCAP (with contemporaneous notification thereof by
                  AMVESCAP to Exchangeco).

         (d)      The Board of Directors of Exchangeco shall determine, in good
                  faith and in its sole discretion, economic equivalence for the
                  purposes of any event referred to in Section 2.7(a) or Section
                  2.7(b) and each such determination shall be conclusive and
                  binding on AMVESCAP. In making each such determination, the
                  following factors shall, without excluding other factors
                  determined by the Board of Directors of Exchangeco to be
                  relevant, be considered by the Board of Directors of
                  Exchangeco:

                  (i)      in the case of any stock dividend or other
                           distribution payable in AMVESCAP Ordinary Shares, the
                           number of such shares issued in proportion to the
                           number of AMVESCAP Ordinary Shares previously
                           outstanding;

                  (ii)     in the case of the issuance or distribution of any
                           rights, options or warrants to subscribe for or
                           purchase AMVESCAP Ordinary Shares (or securities
                           exchangeable for or convertible into or carrying
                           rights to acquire AMVESCAP Ordinary Shares), the


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                           relationship between the exercise price of each such
                           right, option or warrant and the Current Market Price
                           of an AMVESCAP Ordinary Share;

                  (iii)    in the case of the issuance or distribution of any
                           other form of property (including without limitation
                           any shares or securities of AMVESCAP of any class
                           other than AMVESCAP Ordinary Shares, any rights,
                           options or warrants other than those referred to in
                           Section 2.7(d)(ii), any evidences of indebtedness of
                           AMVESCAP or any assets of AMVESCAP), the relationship
                           between the fair market value (as determined by the
                           Board of Directors of Exchangeco in the manner above
                           contemplated) of such property to be issued or
                           distributed with respect to each outstanding AMVESCAP
                           Ordinary Share and the Current Market Price of an
                           AMVESCAP Ordinary Share;

                  (iv)     in the case of any subdivision, redivision or change
                           of the then outstanding AMVESCAP Ordinary Shares into
                           a greater number of AMVESCAP Ordinary Shares or the
                           reduction, combination, consolidation or change of
                           the then outstanding AMVESCAP Ordinary Shares into a
                           lesser number of AMVESCAP Ordinary Shares or any
                           amalgamation, merger, reorganization or other
                           transaction affecting AMVESCAP Ordinary Shares, the
                           effect thereof upon the then outstanding AMVESCAP
                           Ordinary Shares; and

                  (v)      in all such cases, the general taxation consequences
                           of the relevant event to holders of Exchangeable
                           Shares to the extent that such consequences may
                           differ from the taxation consequences to holders of
                           AMVESCAP Ordinary Shares as a result of differences
                           between taxation laws of Canada and the United
                           Kingdom (except for any differing consequences
                           arising as a result of differing marginal taxation
                           rates and without regard to the individual
                           circumstances of holders of Exchangeable Shares).

         (e)      Exchangeco agrees that, to the extent required, upon due
                  notice from AMVESCAP, Exchangeco will use its best efforts to
                  take or cause to be taken such steps as may be necessary for
                  the purposes of ensuring that appropriate dividends are paid
                  or other distributions are made by Exchangeco, or
                  subdivisions, redivisions or changes are made to the
                  Exchangeable Shares, in order to implement the required
                  economic equivalence with respect to the AMVESCAP Ordinary
                  Shares and Exchangeable Shares as provided for in this Section
                  2.7.


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SECTION 2.8 TENDER OFFERS

         In the event that a tender offer, share exchange offer, issuer bid,
take-over bid or similar transaction with respect to AMVESCAP Ordinary Shares
(an "OFFER") is proposed by AMVESCAP or is proposed to AMVESCAP or its
shareholders and is recommended by the Board of Directors of AMVESCAP, or is
otherwise effected or to be effected with the consent or approval of the Board
of Directors of AMVESCAP, and the Exchangeable Shares are not redeemed by
Exchangeco or purchased by Callco pursuant to the Redemption Call Right,
AMVESCAP will expeditiously and in good faith to take all such actions and do
all such things as are reasonably necessary or desirable to enable and permit
holders of Exchangeable Shares (other than AMVESCAP and its Affiliates) to
participate in such Offer to the same extent and on an economically equivalent
basis as the holders of AMVESCAP Ordinary Shares, without discrimination.
Without limiting the generality of the foregoing, AMVESCAP will expeditiously
and in good faith take all such actions and do all such things as are reasonably
necessary or desirable to ensure that holders of Exchangeable Shares may
participate in each such Offer without being required to retract Exchangeable
Shares as against Exchangeco (or, if so required, to ensure that any such
retraction, shall be effective only upon, and shall be conditional upon, the
closing of such Offer and only to the extent necessary to tender or deposit to
the Offer). Nothing herein shall affect the rights of Exchangeco to redeem (or
Callco to purchase pursuant to the Redemption Call Right) Exchangeable Shares,
as applicable, in the event of an AMVESCAP Control Transaction.

SECTION 2.9 OWNERSHIP OF OUTSTANDING SHARES

         Without the prior approval of Exchangeco and the prior approval of the
holders of the Exchangeable Shares given in accordance with section 10(2) of the
Share Provisions, AMVESCAP covenants and agrees in favour of Exchangeco that, as
long as any outstanding Exchangeable Shares or Debentures are owned by any
Person other than AMVESCAP or any of its Affiliates, AMVESCAP will be and remain
the direct or indirect beneficial owner of all issued and outstanding voting
shares in the capital of Exchangeco and Callco.

SECTION 2.10 AMVESCAP AND AFFILIATES NOT TO VOTE EXCHANGEABLE SHARES

         AMVESCAP covenants and agrees that it will appoint and cause to be
appointed proxyholders with respect to all Exchangeable Shares held by it and
its Affiliates for the sole purpose of attending each meeting of holders of
Exchangeable Shares in order to be counted as part of the quorum for each such
meeting. AMVESCAP further covenants and agrees that it will not, and will cause
its Affiliates not to, exercise any voting rights which may be exercisable by
holders of Exchangeable Shares from time to time pursuant to the Share
Provisions or pursuant to the provisions of the OBCA (or any successor or other
corporate statute by which Exchangeco may in the future be governed) with
respect to any Exchangeable Shares


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held by it or by its Affiliates in respect of any matter considered at any
meeting of holders of Exchangeable Shares.

SECTION 2.11 ORDINARY MARKET PURCHASES

         For certainty, nothing contained in this agreement, including without
limitation the obligations of AMVESCAP contained in Section 2.8, shall limit the
ability of AMVESCAP (or any of its subsidiaries including, without limitation,
Callco or Exchangeco) to make ordinary market purchases of AMVESCAP Ordinary
Shares in accordance with applicable laws and regulatory or stock exchange
requirements.

SECTION 2.12 STOCK EXCHANGE LISTING

         AMVESCAP covenants and agrees in favour of Exchangeco that, as long as
any outstanding Exchangeable Shares are owned by any Person other than AMVESCAP
or any of its Affiliates, AMVESCAP will use its best efforts to maintain a
listing for such Exchangeable Shares on the Toronto Stock Exchange.

                                    ARTICLE 3
                               AMVESCAP SUCCESSORS

SECTION 3.1 CERTAIN REQUIREMENTS IN RESPECT OF COMBINATION, ETC.

         As long as any outstanding Exchangeable Shares are owned by any Person
other than AMVESCAP or any of its Affiliates, AMVESCAP shall not consummate any
transaction (whether by way of reconstruction, reorganization, consolidation,
arrangement, merger, transfer, sale, lease or otherwise) whereby all or
substantially all of its undertaking, property and assets would become the
property of any other Person or, in the case of a merger, of the continuing
corporation resulting therefrom unless, but may do so if:

         (a)      such other Person or continuing corporation (the "AMVESCAP
                  SUCCESSOR") by operation of law, becomes, without more, bound
                  by the terms and provisions of this agreement or, if not so
                  bound, executes, prior to or contemporaneously with the
                  consummation of such transaction, an agreement supplemental
                  hereto and such other instruments (if any) as are reasonably
                  necessary or advisable to evidence the assumption by the
                  AMVESCAP Successor of liability for all moneys payable and
                  property deliverable hereunder and the covenant of such
                  AMVESCAP Successor to pay and deliver or cause to be delivered
                  the same and its agreement to observe and perform all the
                  covenants and obligations of AMVESCAP under this agreement;
                  and

         (b)      such transaction shall be upon such terms and conditions as
                  substantially to preserve and not to impair in any material
                  respect any


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                  of the rights, duties, powers and authorities of the other
                  parties hereunder or the holders of the Exchangeable Shares.

SECTION 3.2 VESTING OF POWERS IN SUCCESSOR

         Whenever the conditions of Section 3.1 have been duly observed and
performed, the parties, if required by Section 3.1, shall execute and deliver
the supplemental agreement provided for in Section 3.1(a) and thereupon the
AMVESCAP Successor shall possess and from time to time may exercise each and
every right and power of AMVESCAP under this agreement in the name of AMVESCAP
or otherwise and any act or proceeding by any provision of this agreement
required to be done or performed by the Board of Directors of AMVESCAP or any
officers of AMVESCAP may be done and performed with like force and effect by the
directors or officers of such AMVESCAP Successor.

SECTION 3.3 WHOLLY-OWNED SUBSIDIARIES

         Nothing herein shall be construed as preventing (i) the amalgamation or
merger of any wholly-owned direct or indirect subsidiary of AMVESCAP with or
into AMVESCAP, (ii) the winding-up, liquidation or dissolution of any
wholly-owned direct or indirect subsidiary of AMVESCAP, provided that all of the
assets of such subsidiary are transferred to AMVESCAP or another wholly-owned
direct or indirect subsidiary of AMVESCAP, or (iii) any other distribution of
the assets of any wholly-owned direct or indirect subsidiary of AMVESCAP among
the shareholders of such subsidiary for the purpose of winding up its affairs,
and any such transactions are expressly permitted by this Article 3.

                                    ARTICLE 4
                                     GENERAL

SECTION 4.1 TERM

         This agreement shall come into force and be effective as of the date
hereof and shall terminate and be of no further force and effect at such time as
no Exchangeable Shares (or securities or rights convertible into or exchangeable
for or carrying rights to acquire Exchangeable Shares, including the Debentures)
are held by any Person other than AMVESCAP and any of its Affiliates.

SECTION 4.2 CHANGES IN CAPITAL OF AMVESCAP AND EXCHANGECO

         At all times after the occurrence of any event contemplated pursuant to
Section 2.7 and Section 2.8 or otherwise, as a result of which either AMVESCAP
Ordinary Shares or the Exchangeable Shares or both are in any way changed, this
agreement shall forthwith be amended and modified as necessary in order that it
shall apply with full force and effect, mutatis mutandis, to all new securities
into which AMVESCAP Ordinary Shares or the Exchangeable Shares or both are so


<PAGE>   13
                                     - 13 -


changed and the parties hereto shall execute and deliver an agreement in writing
giving effect to and evidencing such necessary amendments and modifications.

SECTION 4.3 SEVERABILITY

         If any term or other provision of this agreement is invalid, illegal or
incapable of being enforced by any rule or law, or public policy, all other
conditions and provisions of this agreement shall nevertheless remain in full
force and effect so long as the economic or legal substance of the transactions
contemplated hereby is not affected in any manner materially adverse to any
party. Upon such determination that any term or other provision is invalid,
illegal or incapable of being enforced, the parties hereto shall negotiate in
good faith to modify this agreement so as to effect the original intent of the
parties as closely as possible in an acceptable manner to the end that the
transactions contemplated hereby are fulfilled to the fullest extent possible.

SECTION 4.4 AMENDMENTS, MODIFICATIONS

(1)      Subject to Sections 4.2, 4.3 and 4.5, this agreement may not be amended
         or modified except by an agreement in writing executed by Exchangeco,
         Callco and AMVESCAP and approved by the holders of the Exchangeable
         Shares in accordance with section 10(2) of the Share Provisions.

(2)      No amendment or modification or waiver of any of the provisions of this
         agreement otherwise permitted hereunder shall be effective unless made
         in writing and signed by all of the parties hereto.

SECTION 4.5 MINISTERIAL AMENDMENTS

         Notwithstanding the provisions of Section 4.4, the parties to this
agreement may in writing at any time and from time to time, without the approval
of the holders of the Exchangeable Shares, amend or modify this agreement for
the purposes of:

         (a)      adding to the covenants of any or all parties provided that
                  the Board of Directors of each of Exchangeco, Callco and
                  AMVESCAP shall be of the good faith opinion that such
                  additions will not be prejudicial to the rights or interests
                  of the holders of the Exchangeable Shares;

         (b)      making such amendments or modifications not inconsistent with
                  this agreement as may be necessary or desirable with respect
                  to matters or questions which, in the good faith opinion of
                  the Board of Directors of each of Exchangeco, Callco and
                  AMVESCAP, it may be expedient to make, provided that each such
                  Board of Directors shall be of the good faith opinion that
                  such amendments or modifications will not be


<PAGE>   14
                                     - 14 -


                  prejudicial to the rights or interests of the holders of the
                  Exchangeable Shares; or

         (c)      making such changes or corrections which, on the advice of
                  counsel to Exchangeco, Callco and AMVESCAP, are required for
                  the purpose of curing or correcting any ambiguity or defect or
                  inconsistent provision or clerical omission or mistake or
                  manifest error, provided that the Boards of Directors of each
                  of Exchangeco, Callco and AMVESCAP shall be of the good faith
                  opinion that such changes or corrections will not be
                  prejudicial to the rights or interests of the holders of the
                  Exchangeable Shares.

SECTION 4.6 MEETING TO CONSIDER AMENDMENTS

         Exchangeco, at the request of AMVESCAP, shall call a meeting or
meetings of the holders of the Exchangeable Shares for the purpose of
considering any proposed amendment or modification requiring approval pursuant
to Section 4.4. Any such meeting or meetings shall be called and held in
accordance with the bylaws of Exchangeco, the Share Provisions and all
applicable laws.

SECTION 4.7 ENUREMENT

         This agreement shall be binding upon and enure to the benefit of the
parties hereto and their respective successors and assigns.

SECTION 4.8 NOTICES TO PARTIES

(1)      All notices and other communications between the parties to this
         agreement shall be in writing and shall be deemed to have been given if
         delivered personally or by confirmed telecopy to the parties at the
         following addresses (or at such other address for any such party as
         shall be specified in like notice):

                  c/o AMVESCAP PLC
                  11 Devonshire Square
                  London, England
                  EC2M 4Y2
                  Attention: Corporate Secretary
                  Telecopier No.: 011-44-207-929-5889

                  with a copy (which shall not constitute notice) to:

                  Stikeman Elliott
                  5300 Commerce Court West
                  199 Bay Street
                  Toronto, Ontario
                  M5L 1B9
                  Attention: Mr. John M. Stransman
                  Telecopier No.: (416) 947-0866


<PAGE>   15
                                     - 15 -


(2)      Any notice or other communication given personally shall be deemed to
         have been given and received upon delivery thereof and if given by
         telecopy shall be deemed to have been given and received on the date of
         confirmed receipt thereof unless such day is not a Business Day, in
         which case it shall be deemed to have been given and received upon the
         immediately following Business Day.

SECTION 4.9 COUNTERPARTS

         This agreement may be executed in counterparts, each of which shall be
deemed an original, and all of which taken together shall constitute one and the
same instrument.

SECTION 4.10 JURISDICTION

         This agreement shall be construed and enforced in accordance with the
laws of the Province of Ontario and the laws of Canada applicable therein.

SECTION 4.11 ATTORNMENT

         Each of the parties hereto agrees that any action or proceeding arising
out of or relating to this agreement may be instituted in the courts of Ontario,
waives any objection which it may have now or hereafter to the venue of any such
action or proceeding, irrevocably submits to the jurisdiction of the said courts
in any such action or proceeding, agrees to be bound by any judgment of the said
courts and not to seek, and hereby waives, any review of the merits of any such
judgment by the courts of any other jurisdiction, and AMVESCAP hereby appoints
Exchangeco at its registered office in the Province of Ontario as attorney for
service of process.

         IN WITNESS WHEREOF, the parties hereto have caused this agreement to be
duly executed as of the date first above written.

                                        AMVESCAP PLC

                                        By: /s/ ROBERT F. MCCULLOUGH
                                            ------------------------------------
                                            Authorized Signing Officer

                                        AVZ CALLCO INC.

                                        By: /s/ [ILLEGIBLE]
                                            ------------------------------------
                                            Authorized Signing Officer

                                        AMVESCAP INC.

                                        By: /S/ [ILLEGIBLE]
                                            ------------------------------------
                                            Authorized Signing Officer