BIOGEN INC. — Director's Dealing 2010

Jun 21, 2010

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: BIOGEN IDEC INC. (BIIB)
CIK: 0000875045
Period of Report: 2010-06-18

Reporting Person: DORSA CAROLINE (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2010-06-18	Common Stock	P	203	$49.1459	Acquired	7493	Direct

Footnotes

F1: 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.

F2: Purchase pursuant to a trading plan intended to comply with Rule 10b5-1 of the Securities Exchange Act of 1934.

F3: This represents the weighted average price for shares purchased at a range between $49.10 (low) and $49.72 (high).