SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* HANNA NABIL (Last) (First) (Middle) 3030 CALLAN RD (Street) SAN DIEGO CA 92121 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol BIOGEN IDEC INC [ BIIB ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director 10% Owner X Officer (give title below) Other (specify below) EVP Discovery Research
	3. Date of Earliest Transaction (Month/Day/Year) 04/05/2004
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) X Form filed by One Reporting Person Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	03/31/2004		J(1)		615.9	A	$31.399	450,904.9	D
Common Stock	04/01/2004		M		25,000	A	$0.5	475,904.9	D
Common Stock	04/01/2004		S(2)		25,000	D	$55.31	450,904.9	D
Common Stock	04/01/2004		M		20,551	A	$0.5	471,455.9	D
Common Stock	04/01/2004		S(2)		20,551	D	$55.25	450,904.9	D
Common Stock	04/01/2004		M		8,921	A	$0.5	459,825.9	D
Common Stock	04/01/2004		S(2)		8,921	D	$55.1	450,904.9	D
Common Stock	04/01/2004		M		16,079	A	$0.4271	466,983.9	D
Common Stock	04/01/2004		S(2)		16,079	D	$55.1	450,904.9	D
Common Stock	04/01/2004		M		34,449	A	$0.4271	485,353.9	D
Common Stock	04/01/2004		S(2)		34,449	D	$55.25	450,904.9	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Incentive Stock Option (right to buy)(3)	$0.4271	04/01/2004		M			16,079	(4)	01/24/2005	Common Stock	16,079	(3)	55,921	D
Incentive Stock Option (right to buy)(3)	$0.4271	04/01/2004		M			34,449	(4)	01/24/2005	Common Stock	34,449	(3)	21,472	D
Incentive Stock Option (right to buy)(3)	$0.5	04/01/2004		M			25,000	(5)	09/12/2004	Common Stock	25,000	(3)	77,068	D
Incentive Stock Option (right to buy)(3)	$0.5	04/01/2004		M			20,551	(5)	09/12/2004	Common Stock	20,551	(3)	56,517	D
Incentive Stock Option (right to buy)(3)	$0.5	04/01/2004		M			8,921	(5)	09/12/2004	Common Stock	8,921	(3)	47,596	D

Explanation of Responses:

1. Acquisition of shares under the Employee Stock Purchase Plan in a transaction exempt under SEC Rule 16b-3(c).

2. Represents sale by Nabil Hanna pursuant to a qualified written selling plan under SEC rule 10b5-1.

3. Granted under Issuer's Employee Stock Option Plan, in an exempt transaction under SEC rule 16b-3(d).

4. Option becomes exercisable as to 25% of the optioned shares on 1/25/96 and as to the balance of the shares in 36 equal monthly installments thereafter.

5. Option becomes exercisable for 25% of the optioned shares on 9/13/95 and as to the balance of the optioned shares in 36 equal monthly installments thereafter, subject to acceleration in the event the Issuer was to achieve a designated milestone.

	By: Benjamin S. Harshbarger For: Nabil Hanna	04/05/2004
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
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