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                                                                    EXHIBIT 4.20

                            SECOND AMENDMENT TO THE
                           AMVESCAP GLOBAL STOCK PLAN
             (Amended and Restated Effective as of January 1, 1997)
             ------------------------------------------------------

     Acting pursuant to Section 10.5 of the AMVESCAP Global Stock Plan (the
"Plan"), the Remuneration Committee of the Board of Directors of AMVESCAP p.l.c.
hereby amends the Plan, effective as of January 1, 2001, as follows:

     1.  The definition of "Trust" contained in Article II of the Plan is hereby
amended to read in its entirety as follows:

     "Trust" shall mean the grantor trust of the Company from time to time to
which contributions are made in respect of the Plan and, in the case of any
Subsidiary, the term "Trust" shall be limited to such Subsidiary's Sub-Trust as
described in Section 1.3 of the Trust Agreement.  The Company and the
Subsidiaries intend that, in the event of the insolvency or bankruptcy of the
Company or any Subsidiary, only the assets of the Trust which are attributable
to the aggregate Account Balances of the Company or such Subsidiary's
Participants be available to pay the claims of the Company's or such
Subsidiary's creditors."

     2.  The last sentence of Section 6.4 of the Plan is hereby amended to read
in its entirety as follows:

     "Under no circumstances shall such Shares, cash or other property held in
the Trust revert to the Company or any of its Subsidiaries; however such Shares,
cash or other property shall be available to creditors of the Company or any
Subsidiary in the event of the Company's or such Subsidiary's insolvency in
accordance with the terms and conditions of Section 8.2 and the Trust
Agreement."

     3.  The third and fourth sentences of Section 7.1 of the Plan are hereby
amended to read in their entirety as follows:

     "Upon termination of a Participant's employment with the Company and its
Subsidiaries, the Shares, cash or other property credited to such Participant's
Account in respect of vested Awards shall continue to be invested in Shares,
cash or other property until a complete distribution of the value of the vested
Awards credited to such Account is made to such Participant; provided, however,
that during the period prior to a Participant's Permissive Retirement as
determined by the Management Committee, the Management Committee, in its sole
discretion and upon written notice by such Participant, may direct the Trustee
to sell any Shares or other property credited to such Participant's Account in
respect of vested Awards for cash or other property and direct the investment of
such proceeds in such manner as the Management Committee may
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approve until a complete distribution of the value of the vested Awards
credited to such Account is made to such Participant. The Management Committee
(or its delegate) may, in its sole discretion, consult with the Participant as
to the investment of, or the timing of the distribution or sale of, Shares, cash
or other property credited to a Participant's Account in respect of vested
Awards."

     4.  The second paragraph of Section 8.2 of the Plan is hereby amended to
read in its entirety as follows:

          "The trust agreement creating the Trust contains procedures to the
     following effect:  In the event of the insolvency of the Company or any
     Subsidiary, the assets of the Trust shall be available to pay the claims of
     creditors of the Company or such Subsidiary, as the case may be, as a court
     of competent jurisdiction may direct.  The Company or any Subsidiary shall
     be deemed to be "insolvent" if the Company or such Subsidiary is generally
     unable to pay its debts as they become due, or if the Company is subject to
     a pending proceeding under the bankruptcy laws of the United Kingdom, or if
     such Subsidiary is subject to a pending proceeding under the bankruptcy
     laws of the jurisdiction in which it is organized or incorporated.  In the
     event the Company or any Subsidiary becomes insolvent, the Board of
     Directors and the Chief Executive Officer of the Company or such
     Subsidiary, as the case may be, have a duty to inform the Trustee in
     writing of the Company's or such Subsidiary's insolvency.  Upon receipt of
     such notice, or if the Trustee receives written notice from a person
     claiming to be a creditor of the Company or any Subsidiary alleging such
     insolvency, the Trustee shall cease making payments from the assets of the
     Trust on behalf of the Company or such Subsidiary, shall hold such assets
     for the benefit of creditors of the Company or such Subsidiary, as the case
     may be, and shall resume payments from the assets of the Trust only after
     the Trustee has determined that the Company or such Subsidiary, as the case
     may be, is not, or is no longer, insolvent."

     5.  The last sentence of Section 10.5 of the Plan is hereby amended to read
in its entirety as follows:

          "No portion of the assets held in the Trust shall revert to the
     Company or the Subsidiaries at any time except for the reimbursement of
     taxes pursuant to Section 10.1 and the Trust Agreement; provided that, in
     the event of the insolvency of the Company or any Subsidiary, the assets of
     the Trust shall be available to pay the claims of creditors of the Company
     or such Subsidiary, as the case may be, as provided in Section 8.2 and the
     Trust Agreement."<PAGE>

                                                                    EXHIBIT 4.21

                            THIRD AMENDMENT TO THE
                          AMVESCAP GLOBAL STOCK PLAN
            (Amended and Restated Effective as of January 1, 1997)
            ------------------------------------------------------

     Acting pursuant to Section 10.5 of the AMVESCAP Global Stock Plan (the
"Plan"), the Remuneration Committee of the Board of Directors of AMVESCAP p.l.c.
hereby amends the Plan, effective as of February 1, 2002, as follows:

     1.  The first sentence of the definition of "Management Committee"
contained in Article II of the Plan is hereby amended to read in its entirety as
follows:

     "Management Committee" shall mean the management committee, or any
successor committee, comprised of a majority of United States persons within the
meaning of section 7701(a)(30) of the Code and appointed by the Board of
Directors of AVZ, Inc. from time to time to administer the Plan and direct the
Trustee and serving at the pleasure of the Board of Directors of AVZ, Inc."

     2.  The fifth and sixth sentences of the first paragraph of Article IV of
the Plan are hereby amended to read in their entirety as follows:

     "Management Committee decisions shall be made by a majority of its members
at a meeting (which meeting may be held by telephone) at which there is a quorum
and which has been duly called by any member on no less than 48 hours written
notice; notice may be transmitted by facsimile, telex, courier or by other
reasonable means of transmission.  No notice of any meeting of the Management
Committee need be given to any member who submits a signed waiver of notice,
whether before or after the meeting.  Neither the business to be transacted at,
nor the purpose of, any meeting of the Management Committee need be specified in
a written waiver of notice.  The attendance of any member at a meeting of the
Management Committee shall constitute a waiver of notice of such meeting, except
when the member attends a meeting for the express purpose of objecting, at the
beginning of the meeting, to the transaction of any business on the ground that
the meeting is lawfully called or convened.  At all meetings of the Management
Committee, the presence of a majority of the members of the Management Committee
comprised of a majority of United States persons within the meaning of section
7701(a)(30) of the Code shall constitute a quorum for the transaction of
business.  Except as otherwise provided by law, the vote of a majority of the
members present at any meeting at which a quorum is present (including those who
participate by telephone) shall constitute the action of the Management
Committee.  Any decision reduced to writing and signed by all of the members of
the Management Committee shall be as fully effective as if it had been made at a
meeting duly held."
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     3.  The first sentence of Section 6.3 of the Plan is hereby amended to read
in its entirety as follows:

     "Subject to Sections 6.4, 6.6 and 6.10, an Award shall fully vest on the
November 30th of the third year following the year to which the Award is
attributable."

     4.  The third sentence of Section 7.1 of the Plan is hereby amended to read
in its entirety as follows:

     "Upon termination of a Participant's employment with the Company and its
Subsidiaries, the Shares, cash or other property credited to such Participant's
Account in respect of vested Awards shall continue to be invested in Shares,
cash or other property until a complete distribution of the value of the vested
Awards credited to such Account is made to such Participant; provided, however,
that (i) during the period prior to a Participant's Permissive Retirement as
      -
determined by the Management Committee or (ii) upon a Participant's attainment
                                           --
of age 58, a Participant may request in writing and the Management Committee, if
such a request is made, in its sole discretion, may (but need not) direct the
Trustee to sell any Shares or other property credited to such Participant's
Account in respect of vested Awards for cash or other property and direct the
investment of such proceeds in such manner as the Management Committee may
approve until a complete distribution of the value of the vested Awards credited
to such Account is made to such Participant."

     5.  Section 10.12 of the Plan is hereby amended to read in its entirety as
follows:

     "Section 10.12  Special Rules Regarding Management Committee.
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Notwithstanding any other provision of the Plan, with respect to any power of
the Management Committee described herein that is exercised with respect to a
Participant who is a member of the Management Committee and the exercise of such
power does not affect all Participants relatively equally, such power shall be
exercised with respect to such Participant by the non-Participant members of the
Management Committee who are United States persons within the meaning of section
7701(a)(30) of the Code, if any; provided that, if all members of the Management
                                 -------- ----
Committee are Participants or none of the non-Participant members of the
Management Committee are United States persons within the meaning of section
7701(a)(30) of the Code, then such powers shall be exercised with respect to
such Participants by the members of the Remuneration Committee who are United
States persons within the meaning of section 7701(a)(30) of the Code."

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