UPDATE 1-Icahn files proxy to nominate directors at Biogen

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WASHINGTON, May 2 (Reuters) - Billionaire investor Carl Icahn filed a proxy document on Friday to nominate three directors to the board of biotechnology company Biogen Idec Inc (BIIB.O: Quote, Profile, Research).

Icahn, who has claimed Biogen sabotaged an auction to sell itself, is nominating Alexander Denner, managing director of his Icahn Partners investment vehicle; Richard Mulligan, professor of genetics at Harvard Medical School; and Dr. Anne Young, head of the neurology service at Massachusetts General Hospital, to become Biogen directors.

Last month Biogen rejected Icahn's slate of nominees, saying they had a "single-minded" agenda to sell the company and that it expected a proxy fight. The company has not yet set a date for its 2008 annual meeting.

Biogen's board has nominated directors Cecil Pickett, Lynn Schenk and Phillip Sharp for re-election. It also nominated Stelios Papadopoulos, a retired vice chairman at Cowen & Co, to the board in place of Thomas Keller, who reached the mandatory retirement age.

Cambridge, Massachusetts-based Biogen put itself up for sale in October. It ended the auction in December after failing to attract bidders. (Reporting by Karey Wutkowski, with additional reporting by Deena Beasley in Los Angeles; Editing by Braden Reddall)