BIOGEN INC. — Director's Dealing 2012

Jun 5, 2012

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: BIOGEN IDEC INC. (BIIB)
CIK: 0000875045
Period of Report: 2012-06-04

Reporting Person: Posner Brian S (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2012-06-04	Common Stock	M	2400	$71.38	Acquired	15030	Direct
2012-06-04	Common Stock	S	2400	$126.45	Disposed	12630	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2012-06-04	Stock Option (Right to Buy)	$71.38	M	2400	Disposed	2018-07-22	Common Stock (2400)	Direct

Footnotes

F1: Exercise/sale pursuant to a trading plan intended to comply with Rule 10b5-1 of the Securities Exchange Act of 1934.