BIOGEN INC. — Director's Dealing 2010

Mar 24, 2010

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: BIOGEN IDEC INC. (BIIB)
CIK: 0000875045
Period of Report: 2010-03-22

Reporting Person: SHERWIN STEPHEN A (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2010-03-22	Common Stock	A	500	—	Acquired	500	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2010-03-22	Stock Option (Right to Buy)	$59.82	A	1325	Acquired	2020-03-22	Common Stock (1325)	Direct
2010-03-22	Stock Option (Right to Buy)	$59.82	A	35000	Acquired	2020-03-22	Common Stock (35000)	Direct

Footnotes

F1: The stock options become exercisable in three (3) equal annual installments commencing one year after the grant date of 03/22/2010.

F2: Granted under one of the Issuer's stock option plans, in an exempt transaction under SEC Rule 16(b)-3(d).