BIOGEN INC. — Director's Dealing 2010

Jul 1, 2010

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: BIOGEN IDEC INC. (BIIB)
CIK: 0000875045
Period of Report: 2010-06-30

Reporting Person: DORSA CAROLINE (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2010-06-30	Common Stock	P	205	$48.6324	Acquired	7698	Direct

Footnotes

F1: Purchase 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 purchased at a range between $48.53 (low) and $48.67 (high).

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