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                                                                 EXHIBIT 4.3
                              PHARMACIA CORPORATION

                          AMENDED AND RESTATED BY-LAWS
                            AS ADOPTED MARCH 31, 2000

                                     OFFICES

1. Registered

    The name of the registered agent of the Company is The Corporation Trust
Company and the registered office of the Company shall be located in the City of
Wilmington, County of New Castle, State of Delaware.

2. Other

    The Company shall have offices at such places both within or without the
State of Delaware as the Board of Directors may from time to time designate or
the business of the Company may require.

                             STOCKHOLDERS' MEETINGS

3. Annual Meeting

    An annual meeting of stockholders shall be held on such day and at such time
as may be designated by the Board of Directors for the purpose of electing
Directors and for the transaction of such other business as properly may come
before such meeting. Any previously scheduled annual meeting of the stockholders
may be postponed by resolution of the Board of Directors upon public notice
given on or prior to the date previously scheduled for such annual meeting of
stockholders.

4. Business to be Conducted at Annual Meeting

    (a) At an annual meeting of stockholders, only such business shall be
conducted as shall have been brought before the meeting (i) pursuant to the
Company's notice of the meeting, (ii) by or at the direction of the Board of
Directors or (iii) by any stockholder of the Company who is a stockholder of
record at the time of giving of the notice provided for in this By-Law, who
shall be entitled to vote at such meeting and who shall have complied with the
notice procedures set forth in this By-Law.

    (b) For business to be properly brought before an annual meeting by a
stockholder pursuant to Section (a)(iii) of this By-Law, notice in writing must
be delivered or mailed to the Secretary and received at the principal offices of
the Company, not less than 90 days nor more than 120 days prior to the first
anniversary of the preceding year's annual meeting; provided, however, that in
the event that the date of the meeting is advanced by more than 30 days or
delayed by more than 60 days from such anniversary date, notice by the
stockholder must be received not earlier than the 120th
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day prior to such annual meeting and not later than the close of business on the
later of the 90th day prior to such annual meeting or the tenth day following
the day on which public announcement of the date of the annual meeting is first
made. Such stockholder's notice shall set forth as to each matter the
stockholder proposes to bring before the annual meeting (i) a brief description
of the business to be brought before the annual meeting and the reasons for
conducting such business at such meeting; (ii) the name and address, as they
appear on the Company's books, of the stockholder proposing such business, and
the name and address of the beneficial owner, if any, on whose behalf the
proposal is made; (iii) the class and number of shares of the Company's stock
which are beneficially owned by the stockholder, and by the beneficial owner, if
any, on whose behalf the proposal is made; and (iv) any material interest of the
stockholder, and of the beneficial owner, if any, on whose behalf the proposal
is made, in such business. For purposes of these By-Laws, "public announcement"
shall mean disclosure in a press release reported by the Dow Jones News Service,
Associated Press or comparable news service or in a document publicly filed by
the Company with the Securities and Exchange Commission pursuant to Section 13,
14 or 15(b) of the Securities Exchange Act of 1934, as amended.

    (c) Notwithstanding anything in these By-Laws to the contrary, no business
shall be conducted at an annual meeting except in accordance with the procedures
set forth in this By-Law. The chairman of the meeting may, if the facts warrant,
determine that the business was not properly brought before the meeting in
accordance with the provisions of this By-Law; and if the chairman should so
determine, the chairman shall so declare to the meeting, and any such business
not properly brought before the meeting shall not be transacted. Notwithstanding
the foregoing provisions of this By-Law, a stockholder shall also comply with
all applicable requirements of the Securities Exchange Act of 1934, as amended,
(the "Exchange Act") and the rules and regulations thereunder with respect to
the matters set forth in this By-Law. Nothing in this By-Law shall be deemed to
affect any rights of stockholders to request inclusion of proposals in the
Company's proxy statement pursuant to Rule 14a-8 under the Exchange Act. The
provision of this Section 4 shall also govern what constitutes timely notice for
purposes of Rule 14a-4(c) of the Exchange Act.

5. Special Meetings

    Special meetings of stockholders, unless otherwise provided by the law of
Delaware, may be called by the Chairman of the Board or the Chief Executive
Officer, or pursuant to resolution of the Board of Directors, and such person
calling the meeting shall have the sole right to determine the proper purpose or
purposes of such meeting. Business transacted at a special meeting of
stockholders shall be confined to the purpose or purposes of the meeting as
stated in the notice of such meeting. Any previously scheduled special meeting
of the stockholders may be postponed by resolution of the Board of Directors
upon notice by public announcement given on or prior to the date previously
scheduled for such special meeting of stockholders.

6. Place of Meetings
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    Meetings of stockholders shall be held at a location determined by
resolution of the Board of Directors.

7. Notice of Meetings

    Except as otherwise required by the law of Delaware, notice of each meeting
of the stockholders, whether annual or special, shall, at least ten days but not
more than sixty days before the date of the meeting, be given to each
stockholder of record entitled to vote at the meeting by mailing such notice in
the United States mail, postage prepaid, addressed to such stockholder at such
stockholder's address as the same appears on the records of the Company. Such
notice shall state the place, date and hour of the meeting, and in the case of a
special meeting, shall also state the purpose or purposes thereof.

8. Nominations of Directors

    (a) Only persons who are nominated in accordance with the procedures set
forth in these By-Laws shall be eligible for election as Directors. Nominations
of persons for election to the Board of Directors may be made at a meeting of
stockholders (i) by or at the direction of the Board of Directors or (ii) by any
stockholder of the Company who is a stockholder of record at the time of giving
of the notice provided for in this By-Law, who shall be entitled to vote for the
election of Directors at the meeting and who complies with the notice procedures
set forth in this By-Law.

    (b) Nominations by stockholders shall be made pursuant to notice in writing,
delivered or mailed to the Secretary and received at the principal offices of
the Company (i) in the case of an annual meeting, not less than 60 days nor more
than 90 days prior to the first anniversary of the preceding year's annual
meeting, provided, however, that in the event that the date of the meeting is
advanced by more than 30 days or delayed by more than 60 days from such
anniversary date, notice by the stockholder must be received not earlier than
the 90th day prior to such annual meeting and not later than the close of
business on the later of the 60th day prior to such annual meeting or the tenth
day following the day on which public announcement of the date of the meeting is
first made; or (ii) in the case of a special meeting at which directors are to
be elected, not earlier than the 90th day prior to such special meeting and not
later than the close of business on the later of the 60th day prior to such
special meeting or the tenth day following the day on which public announcement
of the date of the meeting and of the nominees proposed by the Board of
Directors to be elected at such meeting is first made. In the case of a special
meeting of stockholders at which Directors are to be elected, stockholders may
nominate a person or persons (as the case may be) for election only to such
position(s) as are specified in the Company's notice of meeting as being up for
election at such meeting. Such stockholder's notice shall set forth (i) as to
each person whom the stockholder proposes to nominate for election or reelection
as a Director, all information relating to such person that would be required to
be disclosed in solicitations of proxies for election of Directors, or is
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otherwise required, in each case pursuant to Regulation 14A under the Exchange
Act (including such person's written consent to being named as a nominee and to
serving as a Director if elected); (ii) as to the stockholder giving the notice,
the name and address, as they appear on the Company's books, of such stockholder
and the class and number of shares of the Company's stock which are beneficially
owned by such stockholder; and (iii) as to any beneficial owner on whose behalf
the nomination is made, the name and address of such person and the class and
number of shares of the Company's stock which are beneficially owned by such
person. At the request of the Board of Directors, any person nominated by the
Board of Directors for election as a Director shall furnish to the Secretary
that information required to be set forth in a stockholder's notice of
nomination which pertains to the nominee. Notwithstanding anything in this
By-Law to the contrary, in the event that the number of directors to be elected
to the Board of Directors of the Company is increased and there is no public
statement naming all the nominees for Director or specifying the size of the
increased Board of Directors made by the Company at least 70 days prior to the
first anniversary of the preceding year's annual meeting, a stockholder's notice
required by this By-Law shall also be considered timely, but only with respect
to nominees for any new positions created by such increase, if it shall be
delivered to the Secretary at the principal offices of the Company not later
than the close of business on the 10th day following the day on which such
public announcement is first made by the Company.

    (c) No person shall be eligible for election as a Director of the Company
unless nominated in accordance with the procedures set forth in these By-Laws.
The chairman of the meeting may, if the facts warrant, determine that a
nomination was not made in accordance with the procedures prescribed in this
By-Law; and if the chairman should so determine, the chairman shall so declare
to the meeting, and the defective nomination shall be disregarded.
Notwithstanding the foregoing provisions of this By-Law, a stockholder shall
also comply with all applicable requirements of the Exchange Act and the rules
and regulations thereunder with respect to the matters set forth in this By-Law.
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9. List of Stockholders

    (a) The Secretary of the Company shall prepare, at least ten days before
each meeting of stockholders, a complete list of the stockholders entitled to
vote at the meeting, arranged in alphabetical order, and showing the address of
each stockholder and the number of shares registered in the name of each
stockholder. Such list shall be open to the examination of any stockholder, for
any purpose germane to the meeting, during ordinary business hours, for a period
of at least ten days prior to the meeting, either at a place within the city
where the meeting is to be held, which place shall be specified in the notice of
the meeting, or, if not so specified, at the place where the meeting is to be
held. The list shall also be produced and kept at the time and place of the
meeting during the whole time thereof, and may be inspected by any stockholder
who is present.

    (b) The stock ledger of the Company shall be the only evidence as to the
identity of the stockholders entitled (i) to vote in person or by proxy at any
meeting of stockholders, or (ii) to exercise the rights in accordance with
Delaware law to examine the stock ledger, the list required by this By-Law or
the books and records of the Company.

10. Quorum

    The holders of a majority of the stock issued and outstanding and entitled
to vote thereat, present in person or represented by proxy, shall constitute a
quorum for the transaction of any business at all meetings of the stockholders,
except as otherwise provided by the law of Delaware, by the Certificate of
Incorporation or by these By-Laws. The stockholders present at any duly
organized meeting may continue to transact business until adjournment,
notwithstanding the withdrawal of sufficient stockholders to render the
remaining stockholders less than a quorum. Whether or not a quorum is present,
either the chairman of the meeting or a majority of the stockholders entitled to
vote thereat, present in person or by proxy, shall have power to adjourn the
meeting from time to time, without notice other than announcement at the
meeting. If the adjournment is for more than thirty days, or if after the
adjournment a new record date is fixed for the adjourned meeting, a notice of
the adjourned meeting shall be given to each stockholder of record entitled to
vote at the meeting. At such adjourned meeting at which the requisite amount of
voting stock shall be present or represented, any business may be transacted
which might have been transacted at the meeting as originally noticed.

11. Voting and Required Vote

    Subject to the provisions of the Certificate of Incorporation, each
stockholder shall, at every meeting of stockholders, be entitled to one vote for
each share of capital stock held by such stockholder. Subject to the provisions
of the Certificate of Incorporation and Delaware law, Directors shall be chosen
by the vote of a plurality of the shares present in person or represented by
proxy at the meeting; and all other questions shall
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be determined by the affirmative vote of the majority of shares present in
person or represented by proxy at the meeting. In all matters, votes cast in
accordance with any method adopted by the Company shall be valid so long as such
method is permitted under Delaware law.

12. Proxies

    Each stockholder entitled to vote at a meeting of stockholders may authorize
another person or persons to act for such stockholder by proxy, in any manner
permitted by law. No proxy shall be voted or acted upon after three years from
its date, unless the proxy provides for a longer period.

13.  Inspectors of Election; Polls

    Before each meeting of stockholders, the Chairman of the Board or another
officer of the Company designated by resolution of the Board of Directors shall
appoint one or more inspectors of election for the meeting and may appoint one
or more inspectors to replace any inspector unable to act. If any of the
inspectors appointed shall fail to attend, or refuse or be unable to serve,
substitutes shall be appointed by the chairman of the meeting. Each inspector
shall have such duties as are provided by law, and shall take and sign an oath
faithfully to execute the duties of inspector with strict impartiality and
according to the best of such person's ability. The chairman of the meeting
shall fix and announce at the meeting the date and time of the opening and
closing of the polls for each matter upon which the stockholders will vote at
the meeting.

14. Organization

    The Chairman of the Board of Directors, or in the Chairman's absence, (i)
the Chief Executive Officer, if a member of the Board of Directors, (ii) one of
the Vice Chairmen of the Board who is a member of the Board of Directors, if
any, in such order as may be designated by the Chairman of the Board, in that
order, or (iii) in the absence of each of them, a chairman chosen by a majority
of the Directors present, shall act as chairman of the meetings of the
stockholders. The order of business and the procedure at any meeting of
stockholders shall be determined by the chairman of the meeting.

15. No Stockholder Action by Written Consent

    Any action required or permitted to be taken by the stockholders of the
Company must be effected at a duly called annual or special meeting of
stockholders of the Company and may not be effected by any consent in writing in
lieu of a meeting of such stockholders.

                               BOARD OF DIRECTORS

16. General Powers, Number, Term of Office
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    The business of the Company shall be managed under the direction of its
Board of Directors. Subject to the rights of the holders of any series of
preferred stock, par value $0.01 per share, of the Company ("Preferred Stock")
to elect additional directors under specified circumstances, the number of
directors of the Company which shall constitute the whole Board shall be not
less than five nor more than 20. The exact number of directors within the
minimum and maximum limitation specified in the preceding sentence shall be
fixed from time to time exclusively by resolution of a majority of the whole
Board. The Directors, other than those who may be elected by the holders of any
series of Preferred Stock, shall be divided into three classes, as nearly equal
in number as possible. One class of directors shall have a term expiring at the
annual meeting of stockholders to be held in 2000, another class shall have a
term expiring at the annual meeting of stockholders to be held in 2001, and
another class shall have a term expiring at the annual meeting of stockholders
to be held in 2002. Members of each class shall hold office until their
successors are elected and qualified. At each annual meeting of the stockholders
of the Company commencing with the 2000 annual meeting, (1) directors elected to
succeed those directors whose terms then expire shall be elected to hold office
for a term expiring at the third succeeding annual meeting of stockholders after
their election, with each director to hold office until his or her successor
shall have been duly elected and qualified, and (2) only if authorized by a
resolution of the Board of Directors, directors may be elected to fill any
vacancy on the Board of Directors, regardless of how such vacancy shall have
been created. Directors need not be stockholders of the Company or residents of
the State of Delaware.

17. Vacancies

    Subject to the rights of the holders of any series of Preferred Stock to
elect additional directors under specified circumstances, and unless the Board
of Directors otherwise determines, vacancies resulting from death, resignation,
retirement, disqualification, removal from office or other cause, and newly
created directorships resulting from any increase in the authorized number of
directors, may be filled only by a director nominated by the nominating
committee and approved by the affirmative vote of a majority of the remaining
directors, though less than a quorum of the Board of Directors, or by a sole
remaining director, and directors so chosen shall hold office for a term
expiring at the annual meeting of stockholders at which the term of office of
the class to which they have been elected expires and until such director's
successor shall have been duly elected and qualified. No decrease in the number
of authorized directors constituting the Board of Directors shall shorten the
term of any incumbent director.

18. Regular Meetings

    Following the annual meeting of stockholders, the first meeting of each
newly elected Board of Directors may be held, without notice, on the same day
and at the same place as such stockholders' meeting. The Board of Directors by
resolution may provide for the holding of regular meetings and may fix the times
and places at which such meetings shall be held. Notice of regular meetings
shall not be required provided that whenever
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the time or place of regular meetings shall be fixed or changed, notice of such
action shall be given promptly to each director, as provided in Section 19
below, who was not present at the meeting at which such action was taken.

19. Special Meetings

    Special meetings of the Board of Directors shall be held whenever called by
the Chairman of the Board of Directors or the Chief Executive Officer, or in the
absence of each of them, by any Vice Chairman of the Board, in such order as may
be designated by the Chairman of the Board, or by the Secretary at the written
request of a majority of the Directors.

20. Notices

    Notice of any special meeting of the Board of Directors shall be addressed
to each Director at such Director's residence or business address and shall be
sent to such Director by mail, electronic mail, telecopier, telegram or telex or
telephoned or delivered to such Director personally. If such notice is sent by
mail, it shall be sent not later than three days before the day on which the
meeting is to be held. If such notice is sent by electronic mail, telecopier,
telegram or telex, it shall be sent not later than 12 hours before the time at
which the meeting is to be held. If such notice is telephoned or delivered
personally, it shall be received not later than 12 hours before the time at
which the meeting is to be held. Such notice shall state the time, place and
purpose or purposes of the meeting.

21. Quorum

    One-third of the total number of Directors constituting the whole Board, but
not less than two, shall constitute a quorum for the transaction of business at
any meeting of the Board of Directors, but if less than such required number of
Directors for a quorum is present at a meeting, a majority of the Directors
present may adjourn the meeting from time to time without further notice. Except
as otherwise specifically provided by the law of Delaware, the Certificate of
Incorporation or these By-Laws, the act of a majority of the Directors present
at a meeting at which a quorum is present shall be the act of the Board of
Directors.

22. Organization

    At each meeting of the Board of Directors, the Chairman of the Board or, in
the Chairman's absence, (i) the Chief Executive Officer, if a member of the
Board of Directors, (ii) one of the Vice Chairmen of the Board who is a member
of the Board of Directors, if any, in such order as may be designated by the
Chairman of the Board, in that order, or (iii) in the absence of each of them, a
chairman chosen by a majority of the Directors present, shall act as chairman of
the meeting, and the Secretary or, in the Secretary's absence, an Assistant
Secretary or any employee of the Company appointed by the chairman of the
meeting, shall act as secretary of the meeting.
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23. Resignations

    Any Director may resign at any time by giving written notice to the Chairman
of the Board, the Chief Executive Officer or the Secretary of the Company. Such
resignation shall take effect upon receipt thereof or at any later time
specified therein; and, unless otherwise specified therein, the acceptance of
such resignation shall not be necessary to make it effective.

24. Removal

    Subject to the rights of the holders of any series of Preferred Stock to
elect additional directors under specified circumstances, any director may be
removed from office at any time, but only for cause and only by the affirmative
vote of the holders of at least 80 percent of the voting power of the then
outstanding Voting Stock, voting together as a single class. For purposes of
these By-Laws, "Voting Stock" shall mean the outstanding shares of capital stock
of the Company entitled to vote generally in the election of directors.

25. Action Without a Meeting

    Unless otherwise restricted by the Certificate of Incorporation or these
By-Laws, any action required or permitted to be taken at any meeting of the
Board of Directors or of any committee thereof may be taken without a meeting if
all members of the Board or committee, as the case may be, consent thereto in
writing, and the writing or writings are filed with the minutes of proceedings
of the Board or committee.
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26. Location of Books

    Except as otherwise provided by resolution of the Board of Directors and
subject to the law of Delaware, the books of the Company may be kept at the
principal offices of the Company and at such other places as may be necessary or
convenient for the business of the Company.

27. Dividends

    Subject to the provisions of the Certificate of Incorporation and the law of
Delaware, dividends upon the capital stock of the Company may be declared by the
Board of Directors at any regular or special meeting. Dividends may be paid in
cash, in property, or in shares of the Company's capital stock.

28. Compensation of Directors

    Directors shall receive such compensation and benefits as may be determined
by resolution of the Board for their services as members of the Board and
committees. Directors shall also be reimbursed for their expenses of attending
Board and committee meetings. Nothing contained herein shall preclude any
Director from serving the Company in any other capacity and receiving
compensation therefor.

29. Additional Powers

    In addition to the powers and authorities by these By-Laws expressly
conferred upon it, the Board of Directors may exercise all such powers of the
Company and do all such lawful acts and things as are not by statute or by the
Certificate of Incorporation or by these By-Laws directed or required to be
exercised or done by the stockholders.

                             COMMITTEES OF DIRECTORS

30. Designation, Power, Alternate Members

    (a) The Board of Directors shall have an executive committee, a compensation
committee, a nominating and corporate governance committee, an audit and finance
committee, a public affairs and social responsibility committee, a science and
technology committee and may, by resolution or resolutions passed by a majority
of the whole Board, designate one or more additional committees, each committee
to consist of two or more of the Directors of the Company. Any such committee,
to the extent provided in said resolution or resolutions and subject to any
limitations provided by law, shall have and may exercise the powers of the Board
of Directors in the management of the business and affairs of the Company. The
Board of Directors may designate one or more Directors as alternate members of
any committee, who may replace any absent or disqualified member at any meeting
of the committee. If at a meeting of any committee one or more of the members
thereof is absent or disqualified, and if either the Board of Directors has not
so designated any alternate member or members, or the
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number of absent or disqualified members exceeds the number of alternate members
who are present at such meeting, then the member or members of such committee
(including alternates) present at any meeting and not disqualified from voting,
whether or not they constitute a quorum, may unanimously appoint another
Director to act at the meeting in the place of such absent or disqualified
member. The term of office of the members of each committee shall be as fixed
from time to time by the Board; provided, however, that any committee member who
ceases to be a member of the Board shall automatically cease to be a committee
member.

    (b) The executive committee shall have six members, one of whom shall be the
Chief Executive Officer and one of whom shall be the Chairman of the Board (if
not the same person).

    (c) The nominating committee shall have four members. The power of the Board
of Directors to nominate persons for election as Directors is delegated to the
nominating committee. In the event of a vacancy of the nominating committee, the
remaining Directors on the nominating committee shall appoint a replacement
member or members, as applicable.

31. Quorum, Manner of Acting

    At any meeting of a committee, the presence of one-third, but not less than
two, of its members then in office shall constitute a quorum for the transaction
of business; and the act of a majority of the members present at a meeting at
which a quorum is present shall be the act of the committee; provided that in
the event that any member or members of the committee is or are in any way
interested in or connected with any other party to a contract or transaction
being approved at such meeting, or are themselves parties to such contract or
transaction, the act of a majority of the members present who are not so
interested or connected, or are not such parties, shall be the act of the
committee. Each committee may provide for the holding of regular meetings, make
provision for the calling of special meetings and, except as otherwise provided
in these By-Laws or by resolution of the Board of Directors, make rules for the
conduct of its business.

32. Minutes

    The committees shall keep minutes of their proceedings and report the same
to the Board of Directors when required; but failure to keep such minutes shall
not affect the validity of any acts of the committee or committees.
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                               ADVISORY DIRECTORS

33. Advisory Directors

    The Board of Directors may, by resolution adopted by a majority of the whole
Board, appoint such number of senior executives of the Company as Advisory
Directors as the Board may from time to time determine. The Advisory Directors
shall have such advisory responsibilities as the Chairman of the Board may
designate and the term of office of such Advisory Directors shall be as fixed by
the Board.

                                    OFFICERS

34. Designation

    The officers of the Company shall be a Chairman of the Board, a Chief
Executive Officer, a President, one or more Vice Presidents, a Secretary, a
Treasurer and a Controller. The Board of Directors may also elect one or more
Vice Chairmen of the Board, one or more Vice Chairmen of the Company, one or
more Executive Vice Presidents, Senior Vice Presidents, Group Vice Presidents, a
Chief Financial Officer, Deputy and Assistant Secretaries, Deputy and Assistant
Treasurers, Deputy and Assistant Controllers and such other officers as it shall
deem necessary. Any number of offices may be held by the same person. The
Chairman of the Board of Directors shall be chosen from among the Directors.

35. Election and Term

    At least annually, the Board of Directors of the Company shall elect the
officers of the Company and at any time thereafter the Board may elect
additional officers of the Company and each such officer shall hold office until
the officer's successor is elected and qualified or until the officer's earlier
death, resignation, termination of employment or removal.

36. Removal

    Any officer shall be subject to removal or suspension at any time, for or
without cause, by the affirmative vote of a majority of the whole Board of
Directors.

37. Resignations

    Any officer may resign at any time by giving written notice to the Chairman
of the Board, the President or to the Secretary. Such resignation shall take
effect upon receipt thereof or at any later time specified therein; and, unless
otherwise specified therein, the acceptance of such resignation shall not be
necessary to make it effective.

38. Vacancies
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    A vacancy in any office because of death, resignation, removal or any other
cause may be filled for the unexpired portion of the term by the Board of
Directors.

39. Compensation

    The compensation committee of the Board of Directors shall fix the salaries
of all employees of the Company who are subject to the reporting requirements of
Section 16(a) of the Securities Exchange Act of 1934 or any successor statute,
rule or provision, and other members of executive management designated by such
committee.

40. Chairman of the Board

    The Chairman of the Board shall preside at all meetings of the stockholders
and of the Board of Directors, except as may be otherwise required under the law
of Delaware. The Chairman shall act in an advisory capacity with respect to
matters of policy and other matters of importance pertaining to the affairs of
the Company. The Chairman shall, in consultation with the Chief Executive
Officer, establish the agenda for the meetings of the Board of Directors. The
Chairman, alone or with the Chief Executive Officer, one or more of the Vice
Chairmen of the Board, and/or the Secretary shall sign and send out reports and
other messages which are to be sent to stockholders from time to time. The
Chairman shall also perform such other duties as may be assigned to the Chairman
by these By-Laws, the Board of Directors or, if applicable, the Chief Executive
Officer. If Fred Hassan is the Chief Executive Officer of the Company on
September 30, 2001, on such date he shall become Chairman of the Board and Chief
Executive Officer of the Company, unless otherwise determined at such time by
the affirmative vote of at least 80 percent of the whole Board of Directors.

41. Chief Executive Officer

    The Chief Executive Officer, if a member of the Board of Directors, shall,
in the absence of the Chairman of the Board, preside at all meetings of the
stockholders and of the Board of Directors. The Chief Executive Officer shall
have the general and active management and supervision of the business of the
Company. The Chief Executive Officer shall see that all orders and resolutions
of the Board of Directors are carried into effect and shall be responsible to
the Board of Directors for the Company's strategic development, operational
results and for the running of the Company in accordance with policies approved
by the Board of Directors. The Chief Executive Officer shall also perform such
other duties as may be assigned to the Chief Executive Officer by these By-Laws
or the Board of Directors.

42. President

    The President shall perform such duties as may be assigned to the President
by these By-Laws, the Board of Directors or the Chief Executive Officer.
<PAGE>   14
43. Vice Chairmen of the Board; Vice Chairmen

    The Vice Chairmen of the Board, if a member of the Board of Directors,
shall, in the absence of the Chairman of the Board and the Chief Executive
Officer, and in such order as may be designated by the Chairman of the Board,
preside at all meetings of the stockholders and of the Board of Directors. The
Vice Chairmen of the Board and the Vice Chairmen shall perform such other duties
as may be assigned to them by these By-Laws, the Board of Directors or the Chief
Executive Officer.

44. Executive, Senior, Group and other Vice Presidents

    Each Executive Vice President, Senior Vice President, Group Vice President
and each other Vice President shall perform the duties and functions and
exercise the powers assigned to such officer by the Board of Directors or the
Chief Executive Officer.

45. Chief Financial Officer

    The Chief Financial Officer (if any) shall act in an executive financial
capacity. The Chief Financial Officer shall assist the Chairman of the Board and
the Chief Executive Officer in the general supervision of the Company's
financial policies and affairs.

46. Secretary

    The Secretary shall attend all meetings of the Board of Directors and of the
stockholders and record all votes and the minutes of all proceedings in a book
to be kept for that purpose. The Secretary shall give, or cause to be given,
notice of all meetings of the stockholders and special meetings of the Board of
Directors and, when appropriate, shall cause the corporate seal to be affixed to
any instruments executed on behalf of the Company. The Secretary shall also
perform all duties incident to the office of Secretary and such other duties as
may be assigned to the Secretary by these By-Laws, the Board of Directors, the
Chairman of the Board or the Chief Executive Officer.

47. Assistant Secretaries

    The Assistant Secretaries shall, during the absence of the Secretary,
perform the duties and functions and exercise the powers of the Secretary. Each
Assistant Secretary shall perform such other duties as may be assigned to such
Assistant Secretary by the Board of Directors, the Chairman of the Board, the
Chief Executive Officer or the Secretary.

48. Treasurer

    The Treasurer shall have the custody of the funds and securities of the
Company and shall deposit them in the name and to the credit of the Company in
such depositories as may be designated by the Board of Directors or by any
officer or
<PAGE>   15
officers authorized by the Board of Directors to designate such
depositories; disburse funds of the Company when properly authorized by vouchers
prepared and approved by the Controller; and invest funds of the Company when
authorized by the Board of Directors or a committee thereof. The Treasurer shall
render to the Board of Directors, the Chief Executive Officer or the Chief
Financial Officer, whenever requested, an account of all transactions as
Treasurer and shall also perform all duties incident to the office of Treasurer
and such other duties as may be assigned to the Treasurer by these By-Laws, the
Board of Directors, the Chief Executive Officer or the Chief Financial Officer.

49. Assistant Treasurers

    The Assistant Treasurers shall, during the absence of the Treasurer, perform
the duties and functions and exercise the powers of the Treasurer. Each
Assistant Treasurer shall perform such other duties as may be assigned to the
Assistant Treasurer by the Board of Directors, the Chief Executive Officer, the
Chief Financial Officer or the Treasurer.

50. Controller

    The Controller shall serve as the principal accounting officer of the
Company and shall keep full and accurate account of receipts and disbursements
in books of the Company and render to the Board of Directors, the Chief
Executive Officer or the Chief Financial Officer, whenever requested, an account
of all transactions as Controller and of the financial condition of the Company.
The Controller shall also perform all duties incident to the office of
Controller and such other duties as may be assigned to the Controller by these
By-Laws, the Board of Directors, the Chief Executive Officer or the Chief
Financial Officer.
<PAGE>   16
51. Assistant Controllers

    The Assistant Controllers shall, during the absence of the Controller,
perform the duties and functions and exercise the powers of the Controller. Each
Assistant Controller shall perform such other duties as may be assigned to such
officer by the Board of Directors, the Chief Executive Officer, the Chief
Financial Officer or the Controller.

                       COMPANY CHECKS, DRAFTS AND PROXIES

52. Checks, Drafts

    All checks, drafts or other orders for the payment of money by the Company
shall be signed by such person or persons as from time to time may be designated
by the Board of Directors or by any officer or
officers authorized by the Board of Directors to designate such signers; and the
Board of Directors or such officer or officers may determine that the signature
of any such authorized signer may be facsimile.

53. Proxies

    Except as otherwise provided by resolution of the Board of Directors, the
Chairman of the Board, the Chief Executive Officer, the President, any Vice
Chairman of the Board, any Vice President, the Treasurer and any Assistant
Treasurer, the Controller and any Assistant Controller, the Secretary and any
Assistant Secretary of the Company, shall each have full power and authority, in
behalf of the Company, to exercise any and all rights of the Company with
respect to any meeting of stockholders of any corporation in which the Company
holds stock, including the execution and delivery of proxies therefor, and to
consent in writing to action by such corporation without a meeting.

                                  CAPITAL STOCK

54. Stock Certificates

    Each holder of stock in the Company shall be entitled to have a certificate
signed by, or in the name of the Company by, the Chairman of the Board, the
Chief Executive Officer, the President, any Vice Chairman of the Board, any
Executive Vice President, any Senior Vice President, any Group Vice President or
any other Vice President, and by the Secretary or any Assistant Secretary of the
Company, certifying the number of shares owned by such holder in the Company.
Any of or all the signatures on the certificate may be a facsimile. In case any
officer, transfer agent or registrar who has signed or whose facsimile signature
has been placed upon a certificate shall have ceased to be such officer,
transfer agent or registrar before such certificate is issued, it may be issued
by the Company with the same effect as if such person were such officer,
transfer agent or registrar at the date of issue.
<PAGE>   17
55. Record Ownership

    The Company shall be entitled to treat the person in whose name any share,
right or option is registered as the owner thereof, for all purposes, and shall
not be bound to recognize any equitable or other claim to or interest in such
share, right or option on the part of any other person, whether or not the
Company shall have notice thereof, except as otherwise provided by the law of
Delaware.

56. Record Dates

    In order that the Company may determine the stockholders entitled to notice
of or to vote at any meeting of stockholders or any adjournment thereof, or
entitled to receive payment of any dividend or other distribution or allotment
of any rights, or entitled to exercise any rights in respect of any change,
conversion or exchange of stock or for the purpose of any other lawful action,
the Board of Directors may fix a record date, which shall not precede the date
upon which the resolution fixing the record date is adopted by the Board of
Directors and which shall not be more than sixty nor less than ten days before
the date of such meeting, nor more than sixty days prior to any other action.

57. Transfer of Stock

    Transfers of shares of stock of the Company shall be made only on the books
of the Company by the registered holder thereof, or by the registered holder's
attorney thereunto authorized by power of attorney duly executed and filed with
the Secretary or a transfer agent of the Company, and on surrender of the
certificate or certificates for such shares properly endorsed and the payment of
all taxes thereon.

58. Lost, Stolen or Destroyed Certificates

    The Board of Directors may authorize a new certificate or certificates to be
issued in place of any certificate or certificates theretofore issued by the
Company alleged to have been lost, stolen or destroyed, upon the making of an
affidavit of the fact by the person claiming the certificate of stock to be
lost, stolen or destroyed. When authorizing such issue of a new certificate or
certificates, the Board of Directors may, in its discretion and as a condition
precedent to the issuance thereof, require the owner of such lost, stolen or
destroyed certificate or certificates, or the owner's legal representative, to
give the Company a bond sufficient to indemnify it against any claim that may be
made against the Company on account of the alleged loss, theft or destruction of
such certificate or the issuance of such new certificate.

59. Terms of Preferred Stock

    The provisions of these By-Laws, including those pertaining to voting
rights, election of Directors and calling of special meetings of stockholders,
are subject to the terms, preferences, rights and privileges of any then
outstanding class or series of Preferred Stock as set forth in the Certificate
of Incorporation and in any resolutions of the Board
<PAGE>   18
of Directors providing for the issuance of such class or series of Preferred
Stock; provided, however, that the provisions of any such Preferred Stock shall
not affect or limit the authority of the Board of Directors to fix, from time to
time, the number of Directors which shall constitute the whole Board as provided
in Section 16 above, subject to the right of the holders of any class or series
of Preferred Stock to elect additional Directors as and to the extent
specifically provided by the provisions of such Preferred Stock.

                                 INDEMNIFICATION

60. Indemnification

    (a) The Company shall indemnify and hold harmless, to the fullest extent
permitted by applicable law as it presently exists or may hereafter be amended,
any person who was or is made or is threatened to be made a party or is
otherwise involved in any claim, action, suit, or proceeding, whether civil,
criminal, administrative or investigative (a "proceeding") by reason of the fact
that the person, or a person for whom he or she is the legal representative, is
or was a Director, officer, employee or agent of the Company or is or was
serving at the request of the Company as a director, officer, employee,
fiduciary or agent of another corporation or of a partnership, joint venture,
trust, non-profit entity, or other enterprise, including service with respect to
employee benefit plans, against all expense, liability and loss (including
attorneys' fees, judgments, fines, ERISA excise taxes or penalties and amounts
paid or to be paid in settlement) reasonably incurred or suffered by such
person. The right to indemnification conferred in this By-Law shall be a
contract right. Except as provided in paragraph (c) of this By-Law with respect
to proceedings seeking to enforce rights to indemnification, the Company shall
indemnify a person in connection with a proceeding initiated by such person or a
claim made by such person against the Company only if such proceeding or claim
was authorized by the Board of Directors of the Company.

    (b) The Company shall pay the expenses incurred in defending any proceeding
in advance of its final disposition, provided, however, that if and to the
extent required by law the payment of expenses incurred by any person covered
hereunder in advance of the final disposition of the proceeding shall be made
only upon receipt of an undertaking by or on behalf of the affected person to
repay all amounts advanced if it should ultimately be determined that such
person is not entitled to be indemnified under this By-Law or otherwise.

    (c) If a claim for indemnification or payment of expenses under this By-Law
is not paid in full within thirty days, or such other period as might be
provided pursuant to contract, after a written claim therefor has been received
by the Company, the claimant may file suit to recover the unpaid amount of such
claim or may seek whatever other remedy might be provided pursuant to contract.
In any such action the Company shall have the burden of proving that the
claimant was not entitled to the requested indemnification or payment of
expenses under applicable law. If successful in whole or in part, claimant shall
be entitled to be paid the expense of prosecuting such claim.
<PAGE>   19
Neither the failure of the Company (including its Directors, independent legal
counsel or stockholders) to have made a determination prior to the commencement
of such action that indemnification of the claimant is proper in the
circumstances because the claimant has met the applicable standard of conduct
set forth in the General Corporation Law of the State of Delaware, nor an actual
determination by the Company (including its Directors, independent legal counsel
or stockholders) that the claimant has not met such applicable standard of
conduct, shall be a defense to the action or create a presumption that the
claimant has not met the applicable standard of conduct.

    (d) Any determination regarding whether indemnification of any person is
proper in the circumstances because such person has met the applicable standard
of conduct set forth in the General Corporation Law of the State of Delaware
shall be made by independent legal counsel selected by such person with the
consent of the Company (which consent shall not unreasonably be withheld).

    (e) The rights conferred on any person by this By-Law shall not be exclusive
of any other rights which such person may have or hereafter acquire under any
statute, provision of the Certificate of Incorporation, these By-Laws,
agreement, vote of stockholders or disinterested Directors or otherwise.

    (f) Any repeal or modification of the foregoing provisions of this By-Law
shall not adversely affect any right or protection hereunder of any person with
respect to any act or omission occurring prior to or at the time of such repeal
or modification.

                                  MISCELLANEOUS

61. Corporate Seal

    The seal of the Company shall be circular in form, containing the words
"Pharmacia Corporation" and the word "Delaware" on the circumference surrounding
the word "Seal." Said seal may be used by causing it or a facsimile thereof to
be impressed or affixed or in any other manner reproduced.
<PAGE>   20
62. Fiscal Year

    The fiscal year of the Company shall begin on the first day of January in
each year.

63. Auditors

    The Board of Directors shall select certified public accountants to audit
the books of account and other appropriate corporate records of the Company
annually and at such other times as the Board shall determine by resolution.

64. Waiver of Notice

    Whenever notice is required to be given pursuant to the law of Delaware, the
Certificate of Incorporation or these By-Laws, a written waiver thereof, signed
by the person entitled to notice, whether before or after the time stated
therein, shall be deemed equivalent to notice. Attendance of a person at a
meeting of stockholders or the Board of Directors or a committee thereof shall
constitute a waiver of notice of such meeting, except when the stockholder or
Director attends such meeting for the express purpose of objecting, at the
beginning of the meeting, to the transaction of any business because the meeting
is not lawfully called or convened. Neither the business to be transacted at,
nor the purpose of, any regular or special meeting of the stockholders or the
Board of Directors or committee thereof need be specified in any written waiver
of notice unless so required by the Certificate of Incorporation or by these
By-Laws.

                              AMENDMENT TO BY-LAWS

65. Amendments

    Notwithstanding any provision of law which might otherwise permit a lesser
vote or no vote, but in addition to any affirmative vote of the holders of any
series of Preferred Stock of the Company required by law, the Certificate of
Incorporation or any Preferred Stock designation, the affirmative vote of the
holders of at least 80 percent of the voting power of all of the
then-outstanding Voting Stock (as defined in the Certificate of Incorporation),
voting together as a single class, shall be required for the stockholders to
amend or repeal the By-Laws or to adopt new By-Laws. The By-Laws may also be
amended or repealed and new By-Laws may be adopted by the affirmative vote of a
majority of the whole Board of Directors at any regular or special meeting of
the Board of Directors.
<PAGE>   21
                                EMERGENCY BY-LAWS

    These Emergency By-Laws, notwithstanding any different provision in the
Certificate of Incorporation or By-Laws, shall be operative during any emergency
resulting from an attack on the United States or on a locality in which the
Company conducts its business or customarily holds meetings of the Board of
Directors or its stockholders, or during any nuclear or atomic disaster, or
during the existence of any catastrophe, or other similar emergency condition,
as a result of which a quorum of the Board of Directors or a committee thereof
cannot be readily convened for action. These Emergency By-Laws shall cease to be
operative upon termination of such emergency.

    During any such emergency:

        (a) A meeting of the Board of Directors or a committee thereof may be
    called by any officer or Director. Notice of the time and place of the
    meeting shall be given by the person calling the meeting to only such of the
    Directors as it may be feasible to reach at the time and by such means as
    may be feasible at the time. Such notice shall be given at such time in
    advance of the meeting as circumstances permit in the judgment of the person
    calling the meeting.

        (b) The officers or other persons designated on a list approved by the
    Board of Directors before the emergency, all in such order or priority and
    subject to such conditions and for such period of time (not longer than
    reasonably necessary after the termination of the emergency) as may be
    provided in the resolution approving the list, shall, to the extent required
    to constitute a quorum at any meeting of the Board of Directors during the
    emergency, be deemed Directors for such meeting. If at the time of the
    emergency the Board of Directors has not approved such a list of persons,
    then to the extent required to constitute a quorum at any meeting of the
    Board of Directors during the emergency, the officers of the Company who are
    present shall be deemed, in order of rank and within the same rank in order
    of seniority, Directors for such meeting. Two Directors (including persons
    deemed to be Directors) in attendance at the meeting shall constitute a
    quorum.

        (c) The Board of Directors, either before or during any such emergency,
    may provide, and from time to time modify, lines of succession in the event
    that during such an emergency any or all officers or agents of the Company
    shall for any reason be rendered incapable of discharging their duties.

        (d) The Board of Directors, either before or during any such emergency,
    may, effective in the emergency, change the principal offices or designate
    several alternative principal offices or regional offices, or authorize an
    officer, or officers, so to do.

    No officer, Director or employee acting in accordance with these Emergency
By-Laws shall be liable except for willful misconduct.
<PAGE>   22
    These Emergency By-Laws shall be subject to repeal or change by further
action of the Board of Directors or by action of the stockholders, but no such
repeal or change shall modify the provisions of the next preceding paragraph
with regard to action taken prior to the time of such repeal or change. Any
amendment of these Emergency By-Laws may make any further or different provision
that may be practical and necessary for the circumstances of the emergency.