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As filed with the United States Securities and Exchange Commission on November 12, 2003

Registration No. 333-          

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM S-8
REGISTRATION STATEMENT
Under
THE SECURITIES ACT OF 1933

BIOGEN IDEC INC.
(Exact name of registrant as specified in its charter)

Delaware
(State or other jurisdiction of incorporation or organization)

 33-0112644
(I.R.S. Employer Identification No.)

14 Cambridge Center
Cambridge, Massachusetts 02142
(Address of Principal Executive Offices)

Biogen, Inc. 1983 Employee Stock Purchase Plan
Biogen, Inc. 1985 Non-Qualified Stock Option Plan
Biogen, Inc. 1987 Scientific Board Stock Option Plan
Biogen, Inc. 1994 European Employee Stock Purchase Plan
(Full title of the plan)

Thomas J. Bucknum
Biogen Idec Inc.
Executive Vice President, General Counsel and Secretary
14 Cambridge Center
Cambridge, Massachusetts 02142
(617) 679-2000
(Name, address and telephone number, including area code, of agent for service)

CALCULATION OF REGISTRATION FEE

Title of Securities To Be Registered
   Amount to Be
Registered (1)
   Proposed Maximum
Offering Price
per Share(2)
   Proposed Maximum
Aggregate Offering
Price(2)
   Amount of
Registration
Fee(2)
Common Stock, $0.0005 par value per share   21,679,942 shares   $32.965   $714,679,288   $0
(1)
This Registration Statement (the "S-8 Registration Statement") relates to the 21,679,942 shares of the Registrant's Common Stock, par value $0.0005 per share (the "Common Stock"), which were registered on the Registrant's Form S-4/A (File No. 333-107098), declared effective by the United States Securities and Exchange Commission on October 3, 2003 (the "S-4 Registration Statement"). The S-4 Registration Statement effected the registration of an aggregate of 192,759,213 shares of Common Stock, which included: (i) 171,079,271 shares of Common Stock issuable to holders of outstanding shares of Biogen, Inc.'s Common Stock and (ii) 21,679,942 shares of Common Stock (the "Option Shares") issuable upon the exercise of outstanding stock options (the "Biogen Options") to purchase Biogen, Inc.'s Common Stock that were assumed by the Registrant at the closing of the merger of Bridges Merger Corporation, a Massachusetts corporation and wholly owned subsidiary of the Registrant, with and into Biogen, Inc., with Biogen, Inc. surviving as the wholly owned subsidiary of the Registrant (the "Merger"). This S-8 Registration Statement also shall cover any additional shares of Common Stock which become issuable by reason of any stock dividend, stock split, recapitalization or other similar transaction with respect to the Option Shares effected without the Registrant's receipt of consideration that results in an increase in the number of the outstanding shares of the Registrant's Common Stock. The Registrant's Common Stock registered pursuant to this S-8 Registration Statement includes registration of an equal number of rights issuable to the Registrant's stockholders pursuant to and under the circumstances described in the Registrant's Amended and Restated Rights Agreement dated as of July 27, 2001, as amended.
(2)
The registration fee payable pursuant to Rule 457(c) of the Securities Act of 1933 with respect to the Option Shares is $57,818. The Registrant previously paid a registration fee in the amount of $570,748.46 in connection with the S-4 Registration Statement, of which $64,193 pertained to the Option Shares (the "Option Share Registration Fee"). Promptly following the closing of the Merger, the Registrant will issue up to issue up to approximately 171,079,271 shares of Common Stock to holders of outstanding shares of Biogen's common stock. The remaining 21,679,942 shares of Common Stock registered pursuant to the S-4 Registration Statement will not be issued pursuant to the S-4 Registration Statement and instead will be issued to holders of Biogen Options upon the exercise of such options pursuant to this S-8 Registration Statement. Pursuant to Rule 457(p) under the Securities Act of 1933, the Registrant hereby offsets the amount of the fees payable with respect to the Option Shares under this S-8 Registration Statement against the Option Share Registration Fee previously paid.


PART I

INFORMATION REQUIRED IN THE SECTION 10(A) PROSPECTUS

Item 1: Plan Information*

Item 2: Registrant Information and Employee Plan Annual Information*

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PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3: Incorporation of Documents by Reference

        The following documents, which have been previously filed by the Registrant with the United States Securities and Exchange Commission (the "Commission"), are hereby incorporated by reference into this Registration Statement:

        Until such time that a post-effective amendment to this Registration Statement has been filed which indicates that all securities offered hereby have been sold or which deregisters all securities remaining unsold at the time of such amendment, all documents subsequently filed by the Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934 (the "Exchange Act") shall be deemed to be incorporated by reference in this Registration Statement and to be a part hereof from the date of filing of such documents. Any statement contained herein or in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement contained herein or in any subsequently filed document which is also deemed to be incorporated by reference herein modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement.


Item 4: Description of Securities

        Not applicable.


Item 5: Interests of Named Experts and Counsel

        Not applicable.


Item 6: Indemnification of Directors and Officers

        The Registrant's Amended and Restated Certificate of Incorporation limits the liability of directors to the maximum extent permitted by Delaware law. Delaware law provides that directors of a corporation will not be personally liable for monetary damages for breach of their fiduciary duties as directors, except for liability for (i) any breach of their duty of loyalty to the corporation or its

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stockholders, (ii) any acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (iii) any unlawful payments of dividends or unlawful stock purchases or redemptions as provided in Section 174 of the Delaware General Corporation Law or (iv) any transaction from which the director derived an improper personal benefit.

        The Registrant's Bylaws provide that the Registrant shall indemnify its directors and may indemnify its officers and employees and other agents to the fullest extent permitted by law. The Registrant believes that indemnification under its Bylaws covers at least negligence and gross negligence on the part of indemnified parties.

        The Registrant's Bylaws also permit the Registrant to secure insurance on behalf of any officer, director, employee or other agent for any liability arising out of his or her actions in such capacity, regardless of whether the Bylaws have the power to indemnify him or her against such liability under the General Corporation Law of Delaware. The Registrant currently has secured such insurance on behalf of its directors and officers.

        The Registrant has entered into agreements to indemnify its directors and executive officers, in addition to indemnification provided for in its Bylaws. These agreements, among other things, indemnify the Registrant's directors and executive officers for certain expenses (including attorneys' fees), judgments, fines and settlement amounts incurred by any such person in any action or proceeding, including any action by or in the right of the Registrant, arising out of such person's services as a director or executive officer of the Registrant, any subsidiary of the Registrant or any other company or enterprise to which the person provides services at the Registrant's request. The Registrant believes that these provisions and agreements are necessary to attract and retain qualified persons as directors and executive officers.


Item 7: Exemption from Registration Claimed

        Not applicable.


Item 8: Exhibits

Exhibit Number
   Description
4.1(1)   Description of Common Stock.

5.1
 
Opinion of Pillsbury Winthrop LLP.

10.1(2)
 
Biogen, Inc. 1983 Employee Stock Purchase Plan.

10.2(3)
 
Biogen, Inc. 1985 Non-Qualified Stock Option Plan.

10.3(4)
 
Biogen, Inc. 1987 Scientific Board Stock Option Plan.

10.4(5)
 
Biogen, Inc. 1994 European Employee Stock Purchase Plan.

23.1
 
Consent of Independent Auditors—KPMG LLP.

23.2
 
Consent of Pillsbury Winthrop LLP (included in Exhibit 5.1).

23.3
 
Consent of Independent Accountants—PricewaterhouseCoopers LLP.

24.1
 
Powers of Attorney (included in signature page to Registration Statement).
(1)
Reference is made to the description of the Registrant's capital stock contained in the Registrant's Registration Statement on Form S-4/A (File No. 333-107098), which is incorporated herein by reference.

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(2)
Exhibit 10.1 is incorporated herein by reference to Exhibit 10.20 of Biogen, Inc.'s Registration Statement on Form 10-K for the year ended December 31, 2001 (File No. 000-12042) filed on March 29, 2002.

(3)
Exhibit 10.2 is incorporated herein by reference to Exhibit 10.21 of Biogen, Inc.'s Registration Statement on Form 10-K for the year ended December 31, 2002 (File No. 000-12042) filed on March 14, 2003.

(4)
Exhibit 10.3 is incorporated herein by reference to Exhibit 10.22 of Biogen, Inc.'s Registration Statement on Form 10-K for the year ended December 31, 2002 (File No. 000-12042) filed on March 14, 2003.

(5)
Exhibit 10.4 is incorporated herein by reference to Exhibit 10.1 of Biogen, Inc.'s Registration Statement on Form S-8 (File No. 333-63013) filed on September 28, 1995.


Item 9: Undertakings

        (a)   The undersigned Registrant hereby undertakes:

        (b)   The undersigned Registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the Exchange Act (and, where applicable, each filing of an employee benefit plan's annual report pursuant to Section 15(d) of the Exchange Act) that is incorporated by reference in this Registration Statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

        (c)   Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the Commission such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer or controlling person of the Registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

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SIGNATURES

        Pursuant to the requirements of the Securities Act, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Cambridge, Commonwealth of Massachusetts on this 12th day of November 2003.

  BIOGEN IDEC INC.

 
By:
 
/s/  JAMES C. MULLEN      
James C. Mullen
Chief Executive Officer and President


POWER OF ATTORNEY

        KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Thomas J. Bucknum and Anne Marie Cook and each of them, as his or her true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement on Form S-8, and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorney-in-facts and agents, or either of them, or their or his substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

        Pursuant to the requirements of the Securities Act, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

Signature
   Title
   Date

/s/  JAMES C. MULLEN      
James C. Mullen
 
Chief Executive Officer, President and Director (Principal Executive Officer)
 
November 12, 2003

/s/  PETER N. KELLOGG      
Peter N. Kellogg
 
Executive Vice President, Finance and Chief Financial Officer (Principal Financial Officer and Principal Accounting Officer)
 
November 12, 2003

/s/  WILLIAM H. RASTETTER      
William H. Rastetter, Ph.D.
 
Executive Chairman and Director
 
November 12, 2003

    
Alan Belzer
 
Director
 
November    , 2003

    
Lawrence C. Best
 
Director
 
November    , 2003
         

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/s/  ALAN B. GLASSBERG      
Alan B. Glassberg, M.D.
 
Director
 
November 12, 2003

    
Mary L. Good, Ph.D.
 
Director
 
November    , 2003

    
Thomas F. Keller, Ph.D.
 
Director
 
November    , 2003

/s/  ROBERT W. PANGIA      
Robert W. Pangia
 
Director
 
November 12, 2003

/s/  BRUCE R. ROSS      
Bruce R. Ross
 
Director
 
November 12, 2003

/s/  LYNN SCHENK      
Lynn Schenk
 
Director
 
November 12, 2003

    
Phillip A. Sharp, Ph.D.
 
Director
 
November    , 2003

/s/  WILLIAM D. YOUNG      
William D. Young
 
Director
 
November 12, 2003

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EXHIBIT INDEX

Exhibit Number
   Description
4.1(1)   Description of Common Stock.

5.1
 
Opinion of Pillsbury Winthrop LLP.

10.1(2)
 
Biogen, Inc. 1983 Employee Stock Purchase Plan.

10.2(3)
 
Biogen, Inc. 1985 Non-Qualified Stock Option Plan.

10.3(4)
 
Biogen, Inc. 1987 Scientific Board Stock Option Plan.

10.4(5)
 
Biogen, Inc. 1994 European Employee Stock Purchase Plan.

23.1
 
Consent of Independent Auditors—KPMG LLP.

23.2
 
Consent of Pillsbury Winthrop LLP (included in Exhibit 5.1).

23.3
 
Consent of Independent Accountants—PricewaterhouseCoopers LLP.

24.2
 
Powers of Attorney (included in signature page to Registration Statement).
(1)
Reference is made to the description of the Registrant's capital stock contained in the Registrant's Registration Statement on Form S-4/A (File No. 333-107098).

(2)
Exhibit 10.1 is incorporated herein by reference to Exhibit 10.20 of Biogen, Inc.'s Registration Statement on Form 10-K for the year ended December 31, 2001 (File No. 000-12042) filed on March 29, 2002.

(3)
Exhibit 10.2 is incorporated herein by reference to Exhibit 10.21 of Biogen, Inc.'s Registration Statement on Form 10-K for the year ended December 31, 2002 (File No. 000-12042) filed on March 14, 2003.

(4)
Exhibit 10.3 is incorporated herein by reference to Exhibit 10.22 of Biogen, Inc.'s Registration Statement on Form 10-K for the year ended December 31, 2002 (File No. 000-12042) filed on March 14, 2003.

(5)
Exhibit 10.4 is incorporated herein by reference to Exhibit 10.1 of Biogen, Inc.'s Registration Statement on Form S-8 (File No. 333-63013) filed on September 28, 1995.

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PART I INFORMATION REQUIRED IN THE SECTION 10(A) PROSPECTUS
PART II INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
SIGNATURES
POWER OF ATTORNEY
EXHIBIT INDEX