BIOGEN INC. — Director's Dealing 2015

Mar 20, 2015

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: BIOGEN IDEC INC. (BIIB)
CIK: 0000875045
Period of Report: 2015-03-19

Reporting Person: Rowinsky Eric K (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2015-03-19	Common Stock	M	2333	$59.82	Acquired	13643	Direct
2015-03-19	Common Stock	S	2333	$436.137	Disposed	11310	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2015-03-19	Stock Option (Right to Buy)	$59.82	M	2333	Disposed	2020-03-22	Common Stock (2333)	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: Full information regarding the number of shares sold at each separate price wil be provided upon request by the SEC staff, the issuer, or a security holder of the issuer.

F3: This represents the weighted average price for shares sold at a range between $436.06 (low) and $436.15 (high).

F4: The stock options become exercisable in three (3) equal annual installments commencing one year after the grant date of 03/22/2010.