SEC Form 3 
FORM 3	UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940 	  
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1. Name and Address of Reporting Person*
BUCKNUM THOMAS J	

(Last)	(First)	(Middle)	
14 CAMBRIDGE CENTER	

(Street) 
CAMBRIDGE	MA	02142	

(City)	(State)	(Zip)	
	2. Date of Event Requiring Statement (Month/Day/Year)
11/12/2003 	3. Issuer Name and Ticker or Trading Symbol 
BIOGEN IDEC INC [ BIIB ] 		
		4. Relationship of Reporting Person(s) to Issuer 
(Check all applicable) 
	Director		10% Owner	
X	Officer (give title below)		Other (specify below)	
EVP, General Counsel & Sec.	
	5. 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 Beneficially Owned	
1. Title of Security (Instr. 4) 	2. Amount of Securities Beneficially Owned (Instr. 4) 	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 	4. Nature of Indirect Beneficial Ownership (Instr. 5) 	
No Securities Beneficially owned.	0	D		
Table II - Derivative Securities Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities) 	
1. Title of Derivative Security (Instr. 4) 	2. Date Exercisable and Expiration Date (Month/Day/Year)	3. Title and Amount of Securities Underlying Derivative Security (Instr. 4) 	4. Conversion or Exercise Price of Derivative Security 	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 	6. Nature of Indirect Beneficial Ownership (Instr. 5) 	
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares				
Explanation of Responses:	
	Thomas J. Bucknum	11/12/2003	
	** 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 5 (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).	
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.	
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.	
POWER OF ATTORNEY

I, the undersigned, a director and/or an executive officer of Biogen Idec Inc.,
hereby authorize and designate Thomas J. Bucknum, Anne Marie Cook, Jo Ann
Taormina, Benjamin Harshbarger and Kevin M. Foley and each of them acting
alone, as my attorney-in-fact to execute and file on my behalf any and all
Forms 3, 4 and 5 (including any amendments thereto) that I may be required to
file with the United States Securities and Exchange Commission as a result of
my ownership of or transactions in securities of Biogen Idec Inc.  The
authority granted under this power of attorney shall continue for so long as
I am required to file Forms 3, 4 and 5 with regard to my ownership of or
transactions in securities of Biogen Idec Inc., unless earlier revoked in
writing, but shall terminate automatically as to each individual
attorney-in-fact when such person is no longer an employee of Biogen Idec Inc.
I acknowledge that the attorneys-in-fact appointed hereunder are not assuming,
nor is Biogen Idec Inc. assuming, any of my responsibility to comply with
Section 16 of the Securities Exchange Act of 1934.

IN WITNESS WHEREOF, the undersigned has caused this instrument to be duly
executed this 12th day of November, 2003.

                                                /s/ Thomas J. Bucknum
                                                (Signature)

                                                Thomas J. Bucknum