Washington, D.C. 20549
Proxy Statement Pursuant to Section 14(a) of the Securities
Exchange Act of 1934 (Amendment No.  )
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Biogen Idec Inc.
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     As set forth in our definitive proxy statement filed with the Securities and Exchange Commission on May 8, 2008 (the “2008 Proxy Statement”), we are asking our stockholders to consider, among other proposals, a proposal to approve our 2008 Omnibus Equity Plan (the “Plan”) at our 2008 Annual Meeting of Stockholders. The table below reconciles certain equity award information disclosed in or derived from our 2007 Annual Report on Form 10-K filed with the Securities and Exchange Commission on February 14, 2008 (the “2007 10-K”) with the information disclosed in or derived from our 2008 Proxy Statement, and updates that information through May 7, 2008. The Plan remains unchanged and is included as Appendix A to the 2008 Proxy Statement. As of May 7, 2008, 290,297,509 shares of our common stock were outstanding.
Awards Under Equity Plans1
    As of December 31, 2007     As of May 7, 2008  
            2008 Proxy        
    2007 10-K     Statement2     Current 8-K  
Outstanding Awards
Unexercised Options
Average strike price
  $ 50.03     $ 50.03     $ 52.20  
Remaining years
    5.50       *       5.56  
    14,899,721       14,898,252       14,202,886  
Unvested Restricted Stock Units (RSUs)
    4,711,558       4,709,472       5,661,259  
Total Options and RSUs
    19,611,279       19,607,724       19,864,145  
Unvested Restricted Stock Awards (RSAs) 3
    454,766       *       1,650  
Total Options, RSUs and RSAs
    20,066,045       *       19,865,795  
Shares Available for Future Awards
2005 Omnibus Plan
    *       9,749,057       5,156,229  
2006 Directors Plan
    *       661,000       622,525  
Total Shares Available
    *       10,410,057       5,778,754  
*   Not presented in the SEC filing referenced.
1   Except as otherwise noted, amounts represent outstanding awards made pursuant to multiple Biogen Idec equity plans. Among these plans, awards are currently being made only pursuant to the Biogen Idec Inc. 2006 Non-Employee Directors Equity Plan (the “2006 Directors Plan”) and the Biogen Idec Inc. 2005 Omnibus Equity Plan (the “2005 Omnibus Plan”).
2   Differences between amounts reported in the 2007 10-K and 2008 Proxy Statement are due to timing differences in the administrative processing of the granting, vesting or cancellation of an immaterial number of awards. The terms and recipients of those awards were fixed and unchangeable as of their respective grant dates.
3   Represents shares that have already been issued and are included in total shares outstanding.