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EXHIBIT 4a

CERTIFICATE OF AMENDMENT
OF
RESTATED CERTIFICATE OF INCORPORATION
OF
BRISTOL-MYERS SQUIBB COMPANY

        Bristol-Myers Squibb Company, a corporation organized and existing under and by virtue of the General Corporation Law of the State of Delaware, DOES HEREBY CERTIFY:

        FIRST: That at a meeting of the Board of Directors of January 14, 2003 resolutions were duly adopted setting forth a proposed amendment to the Restated Certificate of Incorporation of said corporation, declaring said amendment to be advisable and calling a meeting of stockholders of said corporation for consideration thereof. The resolution setting forth the proposed amendment is as follows:

        RESOLVED, that the Restated Certificate of Incorporation of this corporation be amended by changing paragraph (a) of Article EIGHTH thereof so that, as amended, paragraph (a) of said Article shall be and read as follows:

        "(a) Subject to the rights under Article FOURTH hereof of the holders of any class or series of stock having a preference over the Common Stock as to dividends or upon liquidation to elect additional directors under specified circumstances, the number of, the retirement age of and other restrictions and qualifications for directors of the corporation shall be fixed by the by-laws of the corporation and such number, retirement age and other restrictions and qualifications may be altered only by a majority vote of the entire board of directors from time to time in the manner provided in the by-laws or by amendment thereof adopted by a majority vote of the entire board of directors or adopted by the stockholders; provided, however, that any such amendment adopted by the stockholders must be adopted by the affirmative vote of holders of at least 75% of the outstanding shares of stock of the corporation entitled to vote generally in the election of directors, voting together as a single class.

Except with respect to directors who may be elected by holders of any class or series of stock having a preference over the Common Stock as to dividends or upon liquidation, at the 2004 annual meeting of stockholders, the successors of the directors whose terms expire at that meeting shall be elected for a term expiring at the 2005 annual meeting of stockholders (which number of directors shall be approximately one-third of the total number of directors of the corporation); at the 2005 annual meeting of stockholders, the successors of the directors whose terms expire at that meeting shall be elected for a term expiring at the 2006 annual meeting of stockholders (which number of directors shall be approximately two-thirds of the total number of directors of the corporation); and at each annual meeting of stockholders thereafter, the directors shall be elected for terms expiring at the next annual meeting of stockholders. No decrease in the number of directors constituting the board of directors or change in the restrictions and qualifications for directors shall shorten the term of any incumbent director.

Subject to the rights under Article FOURTH hereof of any class or series of stock having a preference over the Common Stock as to dividends or upon liquidation to elect directors under specified circumstances, any director or the entire board of directors may be removed from office, with or without cause, only by the affirmative vote of the holders of at least 75% of the outstanding shares of stock of the corporation entitled to vote generally in the election of directors, voting together as a single class.

Notwithstanding anything contained in this Certificate of Incorporation to the contrary, the affirmative vote of the holders of at least 75% of the outstanding shares of stock of the corporation entitled to vote generally in the election of directors, voting together as a single class, shall be required to alter, amend, adopt any provision inconsistent with or repeal this Article EIGHTH (a)."

        SECOND: That thereafter, pursuant to resolution of its Board of Directors, the Annual Meeting of Stockholders of said corporation was duly called and held May 6, 2003, upon notice in accordance with Section 222 of the General Corporation Law of the State of Delaware, at which meeting the necessary number of shares as required by statute and the Restated Certificate of Incorporation were voted in favor of the amendment.

        THIRD: That said amendment was duly adopted in accordance with the provisions of Section 242 of the General Corporation Law of the State of Delaware.

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        IN WITNESS WHEREOF, said corporation has caused this certificate to be executed by its duly authorized officer on this 27th day of May, 2003.

BRISTOL-MYERS SQUIBB COMPANY
By:	/s/  SANDRA LEUNG Name: Sandra Leung Title: Vice President and Secretary

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EXHIBIT 4a