BIOGEN INC. — Director's Dealing 2013

Oct 23, 2013

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: BIOGEN IDEC INC. (BIIB)
CIK: 0000875045
Period of Report: 2013-10-22

Reporting Person: Sandrock Alfred (Grp SVP, Chief Medical Officer)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2013-10-22	Common Stock	M	15030	$60.56	Acquired	29530	Direct
2013-10-22	Common Stock	S	15030	$250.108	Disposed	14500	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2013-10-22	Stock Option (Right to Buy)	$60.56	M	15030	Disposed	2018-02-12	Common Stock (15030)	Direct

Footnotes

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

F2: This represents the weighted average price for shares sold at a range between $250.00 (low) and $250.28 (high).

F3: Full information regarding the number of shares sold at each separate price will be provided upon request by the SEC staff, the issuer, or a security holder of the issuer.

F4: The stock options became exercisable in four (4) equal annual installments commencing one year after the grant date of 02/12/08.