BIOGEN INC. — Director's Dealing 2012

Jan 4, 2012

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: BIOGEN IDEC INC. (BIIB)
CIK: 0000875045
Period of Report: 2012-01-03

Reporting Person: LEAMING NANCY (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2012-01-03	Common Stock	M	4000	$55.97	Acquired	10335	Direct
2012-01-03	Common Stock	S	4000	$114.00	Disposed	6335	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2012-01-03	Stock Option (Right to Buy)	$55.97	M	4000	Disposed	2018-01-08	Common Stock (4000)	Direct

Footnotes

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

F2: The stock options become exercisable in three (3) equal annual installments, commencing one year after the grant date of 01/08/2008.