Activision Blizzard (ATVI)

SUPPLEMENT TO PROXY STATEMENT
FOR THE SPECIAL MEETING OF STOCKHOLDERS
TO BE HELD JULY 8, 2008

        This Supplement supplements and amends the Proxy Statement dated June 6, 2008 (the "Proxy Statement") of Activision, Inc. ("Activision" or "we") mailed to you in connection with the solicitation of proxies on behalf of the board of directors of Activision for use at the special meeting of stockholders (the "Special Meeting") to be held at The Peninsula Hotel, 9882 South Santa Monica Boulevard, Beverly Hills, California 90212, on Tuesday, July 8, 2008 at 11:00 a.m., local time. Capitalized terms used herein but not defined have the meaning ascribed to them in the Proxy Statement.

        The purpose of the Special Meeting is to consider and vote on various proposals related to the Business Combination Agreement (the "Business Combination Agreement"), dated December 1, 2007, by and among Activision, Sego Merger Corporation, Vivendi S.A. ("Vivendi"), VGAC LLC, and Vivendi Games, Inc. ("Vivendi Games"). The Proxy Statement seeks to obtain the approval of Activision stockholders for: (a) the issuance of shares of Activision common stock to Vivendi and VGAC LLC in connection with the transactions contemplated by the Business Combination Agreement; (b) the amendment and restatement of our certificate of incorporation, including all of the subproposals set forth in greater detail in the Proxy Statement; (c) the amendment of Section 7.4(a) of our bylaws; and (d) any motion to adjourn or postpone the special meeting to a later date or dates, if necessary, to permit further solicitation of proxies. The Activision board of directors has unanimously approved these proposals. Based on Activision's reasons for the transactions described in the Proxy Statement, the Activision board of directors believes that that the Business Combination Agreement and all related documents and exhibits thereto are in the best interests of Activision and its stockholders and recommends that you vote "FOR" each of the proposals and subproposals described in the Proxy Statement. If you have not already submitted a proxy for use at the special meeting, you are urged to do so promptly.