Amvescap PLC



                                                                                FORM 8.1/8.3

Lodge with a RIS or Newstrack if appropriate and the Takeover Panel.  Use a separate form
 for each class of securities in which dealings have been made.

Date of Disclosure  13 JANUARY 2004

DISCLOSURE UNDER RULES 8.1(a), 8.1(b)(i) and 8.3 OF THE CITY CODE ON TAKEOVERS AND MERGERS

Date of dealing  12 JANUARY 2004

Dealing in (name of company) ... AMERSHAM PLC

    1)Class of securities (eg ordinary shares) ..... ORDINARY 5P SHARES

    2)Amount bought                Amount sold        Price per unit
               -                    11,852                      778P

      Resultant total of the same class owned or controlled (and
    3)percentage of class) ......... 29,026,414 .......... (4.12%)

    4)Party making disclosure...... AMVESCAP PLC

    5)EITHER    (a)    Name of purchaser/vendor (Note 1)
      OR        (b)    If dealing for discretionary client(s), name of fund
                       management organisation

      ...................... AMVESCAP PLC

    6)Reason for disclosure (Note 2)
      (a)    associate of     (i)    offeror (Note 3)                     NO
                              (ii)   offeree company                      NO

      Specify which category or categories of associate (1-8 overleaf)

      If category (8), explain

      (b)    Rule 8.3 (ie disclosure because of ownership or control of 1%
             or more of the class of relevant securities dealt in)      YES

Signed, for and on behalf of the party named in (4) above .. R. CLYDE

(Also print name of signatory) ....... ROBERT CLYDE

Telephone and extension number ....... 020 7065 3720

Note 1.    Specify owner, not nominee or vehicle company.  If relevant, also
           identify controller of owner, eg where an owner normally acts on
           instructions of a controller.

Note 2.    Disclosure might be made for more than one reason; if so, state all reasons.

Note 3.    Specify which offeror if there is more than one.

Note 4.    When an arrangement exists with any offeror, with the offeree company or with an
            associate of any offeror or of the offeree company in relation to relevant
            securities, details of such arrangement must be disclosed, as required by Note 6
            on Rule 8.

Note 5.    It may be necessary, particularly when disclosing derivative transactions, to
            append a sheet to this disclosure form so that relevant information can be
            given.

Note 6.    In the case of an average price bargain, each underlying trade should be
            disclosed.


For full details of disclosure requirements, see Rule 8 of the Code.  If in doubt, contact
 the Panel on Takeovers and Mergers, Monitoring Section, Tel No: 020 7638 0129. Email:
 monitoring@disclosure.org.uk


DEFINITION OF ASSOCIATE

It is not practicable to define associate in terms which would cover all the
different relationships which may exist in an offer. The term associate is
intended to cover all persons (whether or not acting in concert) who directly or
indirectly own or deal in the shares of an offeror or the offeree company in an
offer and who have (in addition to their normal interests as shareholders) an
interest or potential interest, whether commercial, financial or personal, in
the outcome of the offer.

Without prejudice to the generality of the foregoing, the term associate will
normally include the following:--

(1) an offeror's or the offeree company's parent, subsidiaries and fellow
subsidiaries, and their associated companies, and companies of which such
companies are associated companies (for this purpose ownership or control of 20%
or more of the equity share capital of a company is regarded as the test of
associated company status);

(2) banks and financial and other professional advisers (including
stockbrokers)* to an offeror, the offeree company or any company covered in (1),
including persons controlling#, controlled by or under the same control as such
banks, financial and other professional advisers;

(3) the directors (together with their close relatives and related trusts) of an
offeror, the offeree company or any company covered in (1);

(4) the pension funds of an offeror, the offeree company or any company covered
in (1);

(5) any investment company, unit trust or other person whose investments an
associate manages on a discretionary basis, in respect of the relevant
investment accounts;

(6) a person who owns or controls 5% or more of any class of relevant securities
(as defined in paragraphs (a) to (d) in Note 2 on Rule 8) issued by an offeror
or an offeree company, including a person who as a result of any transaction
owns or controls 5% or more. When two or more persons act pursuant to an
agreement or understanding (formal or informal) to acquire or control such
securities, they will be deemed to be a single person for the purpose of this
paragraph. Such securities managed on a discretionary basis by an investment
management group will, unless otherwise agreed by the Panel, also be deemed to
be those of a single person (see Note 8 on Rule 8); and

(7) a company having a material trading arrangement with an offeror or the
offeree company.

Paragraphs (1)-(7) are typical cases. Paragraph (8) below is a category to cover
associate status not within (1)-(7).

(8) Other.

Notes

* References to a "bank" do not apply to a bank whose sole relationship with a
party to an offer is the provision of normal commercial banking services or such
activities in connection with the offer as confirming that cash is available,
handling acceptances and other registration work.

References to "financial and other professional advisers (including
stockbrokers)", in relation to a party to an offer, do not include an
organisation which has stood down, because of a conflict of interest or
otherwise, from acting for that party in connection with the offer. If the
organisation is to have a continuing involvement with that party during the
offer, the Panel must be consulted. Unless the Panel is satisfied that the
involvement is entirely unconnected with the offer, the above exclusion will not
normally apply.

# The normal test for whether a person is controlled by, controls or is under
the same control as another person will be by reference to the definition of
control contained in the Code. There may be other circumstances which the Panel
will regard as giving rise to such a relationship (eg where a majority of the
equity share capital is owned by another person who does not have a majority of
the voting rights); in cases of doubt, the Panel should be consulted.