BIOGEN INC. — Director's Dealing 2011

Mar 3, 2011

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: BIOGEN IDEC INC. (BIIB)
CIK: 0000875045
Period of Report: 2011-03-01

Reporting Person: SCHNEIER CRAIG ERIC (EVP, HR, Public Affairs & Comm)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2011-03-01	Common Stock	M	6250	$49.65	Acquired	23962.2794	Direct
2011-03-01	Common Stock	S	6250	$68.62	Disposed	17712.2794	Direct
2011-03-02	Common Stock	S	4079	$70.1026	Disposed	13633.2794	Direct
2011-03-02	Common Stock	S	3232	$70.0855	Disposed	10401.2794	Direct
2011-03-02	Common Stock	S	200	$70.435	Disposed	10201.2794	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2011-03-01	Stock Option (Right to Buy)	$49.65	M	6250	Disposed	2019-02-24	Common Stock (6250)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	460	Indirect

Footnotes

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

F2: Sale 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 sold at a range between $69.43 (low) and 70.40 (high).

F4: This represents the weighted average price for shares sold at a range between $69.43 (low) and 70.39 (high).

F5: This represents the weighted average price for shares sold at a range between $70.43 (low) and $70.44 (high).

F6: Full information regarding the number of shares sold at each separate price will be provided upon requst by the SEC staff, the issuer, or a security holder of the issuer.

F7: The stock options become exercisable in four (4) equal annual installments commencing one year after the grant date of 02/24/09.