Biogen Idec Stockholders Elect Company’s Board Nominees

Cambridge, MA, June 2008 - Biogen Idec Inc. (NASDAQ: BIIB) today announced that, based on a preliminary count provided by its proxy solicitor, stockholders have elected all four of the Company’s nominees - Cecil B. Pickett, Ph.D., Lynn Schenk, J.D., Phillip A. Sharp, Ph.D., and Stelios Papadopoulos, Ph.D. - to the Biogen Idec Board of Directors at today’s Annual Meeting of Stockholders. In addition, based on that preliminary count, the proposal to amend the Company’s bylaws to set the size of the Board at 12 has been defeated. The preliminary count is subject to the official tabulation of vote results, which will be provided by Biogen Idec’s independent inspector of elections, IVS Associates, Inc., in approximately 2-3 weeks.

Bruce R. Ross, Biogen Idec’s Chairman, said, “We are gratified that our nominees will serve on the Biogen Idec Board of Directors. Our Board has a track record of delivering stockholder value and is committed to pursuing all avenues to continue to do so in the future. We look forward to turning our undivided attention to delivering strong performance and growing our business for stockholders.”

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