SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                  SCHEDULE 13D

                    Under the Securities Exchange Act of 1934
                               (Amendment No.__)*

                                Biogen Idec Inc.
                                (Name of Issuer)

                         Common Stock, Par Value $0.0005
                         (Title of Class of Securities)

                                    09062X103
                                 (CUSIP Number)

                               Marc Weitzen, Esq.
                                Icahn Capital LP
                          767 Fifth Avenue, 47th Floor
                            New York, New York 10153
                                 (212) 702-4388

           (Name, Address and Telephone Number of Person Authorized to
                       Receive Notices and Communications)

                                 August 1, 2008
             (Date of Event which Requires Filing of this Statement)

If the filing person has previously  filed a statement on Schedule 13G to report
the  acquisition  that is the subject of this  Schedule  13D, and is filing this
schedule because of Section  240.13d-1(e),  240.13d-1(f) or 240.13d-1(g),  check
the following box / /.

NOTE:  Schedules  filed in paper format shall include a signed original and five
copies of the schedule, including all exhibits. See Rule 13d-7 for other parties
to whom copies are to be sent.

*The  remainder of this cover page shall be filled out for a reporting  person's
initial filing on this form with respect to the subject class of securities, and
for  any  subsequent   amendment   containing   information  which  would  alter
disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the  Securities  Exchange  Act of
1934 ("Act") or otherwise  subject to the liabilities of that section of the Act
but  shall be  subject  to all other  provisions  of the Act  (however,  see the
Notes).





                                  SCHEDULE 13D

CUSIP No.  09062X103

1  NAME OF REPORTING PERSON
      High River Limited Partnership

2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
      (a) /  /
      (b) / /

3  SEC USE ONLY

4  SOURCE OF FUNDS
      WC

5  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
   ITEMS 2(d) or 2(e)                                                        / /

6  CITIZENSHIP OR PLACE OF ORGANIZATION
      Delaware

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

7  SOLE VOTING POWER
      3,502,261

8  SHARED VOTING POWER
      0

9  SOLE DISPOSITIVE POWER
      3,502,261

10 SHARED DISPOSITIVE POWER
      0

11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
      3,502,261

12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES     / /

13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
      1.21%

14 TYPE OF REPORTING PERSON
      PN





                                  SCHEDULE 13D

CUSIP No.  09062X103

1  NAME OF REPORTING PERSON
      Hopper Investments LLC

2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
      (a) / /
      (b) / /

3  SEC USE ONLY

4  SOURCE OF FUNDS

5  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
   ITEMS 2(d) or 2(e)                                                        / /

6  CITIZENSHIP OR PLACE OF ORGANIZATION
      Delaware

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

7  SOLE VOTING POWER
      0

8  SHARED VOTING POWER
      3,502,261

9  SOLE DISPOSITIVE POWER
      0

10 SHARED DISPOSITIVE POWER
      3,502,261

11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
      3,502,261

12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES     / /

13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
      1.21%

14 TYPE OF REPORTING PERSON
      OO





                                  SCHEDULE 13D

CUSIP No.  09062X103

1  NAME OF REPORTING PERSON
      Barberry Corp.

2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
      (a) / /
      (b) / /

3  SEC USE ONLY

4  SOURCE OF FUNDS

5  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
   ITEMS 2(d) or 2(e)                                                        / /

6  CITIZENSHIP OR PLACE OF ORGANIZATION
      Delaware

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

7  SOLE VOTING POWER
      0

8  SHARED VOTING POWER
      3,502,261

9  SOLE DISPOSITIVE POWER
      0

10 SHARED DISPOSITIVE POWER
      3,502,261

11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
      3,502,261

12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES     / /

13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
      1.21%

14 TYPE OF REPORTING PERSON
      CO





                                  SCHEDULE 13D

CUSIP No.  09062X103

1  NAME OF REPORTING PERSON
      Icahn Partners Master Fund LP

2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
      (a) / /
      (b) / /

3  SEC USE ONLY

4  SOURCE OF FUNDS
      WC

5  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
   ITEMS 2(d) or 2(e)                                                        / /

6  CITIZENSHIP OR PLACE OF ORGANIZATION
      Cayman Islands

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

7  SOLE VOTING POWER
      5,707,871

8  SHARED VOTING POWER
      0

9  SOLE DISPOSITIVE POWER
      5,707,871

10 SHARED DISPOSITIVE POWER
      0

11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
      5,707,871

12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES     / /

13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
      1.97%

14 TYPE OF REPORTING PERSON
      PN





                                  SCHEDULE 13D

CUSIP No.  09062X103

1  NAME OF REPORTING PERSON
      Icahn Partners Master Fund II LP

2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
      (a) / /
      (b) / /

3  SEC USE ONLY

4  SOURCE OF FUNDS
      WC

5  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
   ITEMS 2(d) or 2(e)                                                        / /

6  CITIZENSHIP OR PLACE OF ORGANIZATION
      Cayman Islands

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

7  SOLE VOTING POWER
      1,956,501

8  SHARED VOTING POWER
      0

9  SOLE DISPOSITIVE POWER
      1,956,501

10 SHARED DISPOSITIVE POWER
      0

11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
      1,956,501

12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES     / /

13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
      0.67%

14 TYPE OF REPORTING PERSON
      PN





                                  SCHEDULE 13D

CUSIP No.  09062X103

1  NAME OF REPORTING PERSON
      Icahn Partners Master Fund III LP

2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
      (a) / /
      (b) / /

3  SEC USE ONLY

4  SOURCE OF FUNDS
      WC

5  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
   ITEMS 2(d) or 2(e)                                                        / /

6  CITIZENSHIP OR PLACE OF ORGANIZATION
      Cayman Islands

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

7  SOLE VOTING POWER
      743,575

8  SHARED VOTING POWER
      0

9  SOLE DISPOSITIVE POWER
      743,575

10 SHARED DISPOSITIVE POWER
      0

11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
      743,575

12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES     / /

13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
      0.26%

14 TYPE OF REPORTING PERSON
      PN





                                  SCHEDULE 13D

CUSIP No.  09062X103

1  NAME OF REPORTING PERSON
      Icahn Offshore LP

2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
      (a) / /
      (b) / /

3  SEC USE ONLY

4  SOURCE OF FUNDS

5  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
   ITEMS 2(d) or 2(e)                                                        / /

6  CITIZENSHIP OR PLACE OF ORGANIZATION
      Delaware

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

7  SOLE VOTING POWER
      0

8  SHARED VOTING POWER
      8,407,947

9  SOLE DISPOSITIVE POWER
      0

10 SHARED DISPOSITIVE POWER
      8,407,947

11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
      8,407,947

12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES     / /

13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
      2.90%

14 TYPE OF REPORTING PERSON
      PN





                                  SCHEDULE 13D

CUSIP No.  09062X103

1  NAME OF REPORTING PERSON
      Icahn Partners LP

2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
      (a) / /
      (b) / /

3  SEC USE ONLY

4  SOURCE OF FUNDS
      WC

5  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
   ITEMS 2(d) or 2(e)                                                        / /

6  CITIZENSHIP OR PLACE OF ORGANIZATION
      Delaware

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

7  SOLE VOTING POWER
      5,601,096

8  SHARED VOTING POWER
      0

9  SOLE DISPOSITIVE POWER
      5,601,096

10 SHARED DISPOSITIVE POWER
      0

11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
      5,601,096

12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES     / /

13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
      1.93%

14 TYPE OF REPORTING PERSON
      PN





                                  SCHEDULE 13D

CUSIP No.  09062X103

1  NAME OF REPORTING PERSON
      Icahn Onshore LP

2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
      (a) / /
      (b) / /

3  SEC USE ONLY

4  SOURCE OF FUNDS

5  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
   ITEMS 2(d) or 2(e)                                                        / /

6  CITIZENSHIP OR PLACE OF ORGANIZATION
      Delaware

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

7  SOLE VOTING POWER
      0

8  SHARED VOTING POWER
      5,601,096

9  SOLE DISPOSITIVE POWER
      0

10 SHARED DISPOSITIVE POWER
      5,601,096

11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
      5,601,096

12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES     / /

13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
      1.93%

14 TYPE OF REPORTING PERSON
      PN





                                  SCHEDULE 13D

CUSIP No.  09062X103

1  NAME OF REPORTING PERSON
      Icahn Capital LP

2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
      (a) / /
      (b) / /

3  SEC USE ONLY

4  SOURCE OF FUNDS
      WC

5  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
   ITEMS 2(d) or 2(e)                                                        / /

6  CITIZENSHIP OR PLACE OF ORGANIZATION
      Delaware

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

7  SOLE VOTING POWER
      0

8  SHARED VOTING POWER
      14,009,043

9  SOLE DISPOSITIVE POWER
      0

10 SHARED DISPOSITIVE POWER
      14,009,043

11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
      14,009,043

12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES     / /

13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
      4.83%

14 TYPE OF REPORTING PERSON
      PN





                                  SCHEDULE 13D

CUSIP No.  09062X103

1  NAME OF REPORTING PERSON
      IPH GP LLC

2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
      (a) / /
      (b) / /

3  SEC USE ONLY

4  SOURCE OF FUNDS
      WC

5  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
   ITEMS 2(d) or 2(e)                                                        / /

6  CITIZENSHIP OR PLACE OF ORGANIZATION
      Delaware

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

7  SOLE VOTING POWER
      0

8  SHARED VOTING POWER
      14,009,043

9  SOLE DISPOSITIVE POWER
      0

10 SHARED DISPOSITIVE POWER
      14,009,043

11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
      14,009,043

12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES     / /

13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
      4.83%

14 TYPE OF REPORTING PERSON
      OO





                                  SCHEDULE 13D

CUSIP No.  09062X103

1  NAME OF REPORTING PERSON
      Icahn Enterprises Holdings L.P.

2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
      (a) / /
      (b) / /

3  SEC USE ONLY

4  SOURCE OF FUNDS
      WC

5  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
   ITEMS 2(d) or 2(e)                                                        / /

6  CITIZENSHIP OR PLACE OF ORGANIZATION
      Delaware

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

7  SOLE VOTING POWER
      0

8  SHARED VOTING POWER
      14,009,043

9  SOLE DISPOSITIVE POWER
      0

10 SHARED DISPOSITIVE POWER
      14,009,043

11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
      14,009,043

12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES     / /

13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
      4.83%

14 TYPE OF REPORTING PERSON
      PN





                                  SCHEDULE 13D

CUSIP No.  09062X103

1  NAME OF REPORTING PERSON
      Icahn Enterprises G.P. Inc.

2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
      (a) / /
      (b) / /

3  SEC USE ONLY

4  SOURCE OF FUNDS
      WC

5  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
   ITEMS 2(d) or 2(e)                                                        / /

6  CITIZENSHIP OR PLACE OF ORGANIZATION
      Delaware

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

7  SOLE VOTING POWER
      0

8  SHARED VOTING POWER
      14,009,043

9  SOLE DISPOSITIVE POWER
      0

10 SHARED DISPOSITIVE POWER
      14,009,043

11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
      14,009,043

12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES     / /

13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
      4.83%

14 TYPE OF REPORTING PERSON
      CO





                                  SCHEDULE 13D

CUSIP No.  09062X103

1  NAME OF REPORTING PERSON
      Beckton Corp.

2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
      (a) / /
      (b) / /

3  SEC USE ONLY

4  SOURCE OF FUNDS
      WC

5  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
   ITEMS 2(d) or 2(e)                                                        / /

6  CITIZENSHIP OR PLACE OF ORGANIZATION
      Delaware

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

7  SOLE VOTING POWER
      0

8  SHARED VOTING POWER
      14,009,043

9  SOLE DISPOSITIVE POWER
      0

10 SHARED DISPOSITIVE POWER
      14,009,043

11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
      14,009,043

12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES     / /

13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
      4.83%

14 TYPE OF REPORTING PERSON
      CO





                                  SCHEDULE 13D

CUSIP No.  09062X103

1  NAME OF REPORTING PERSON
      Carl C. Icahn

2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
      (a) / /
      (b) / /

3  SEC USE ONLY

4  SOURCE OF FUNDS

5  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
   ITEMS 2(d) or 2(e)                                                        / /

6  CITIZENSHIP OR PLACE OF ORGANIZATION
      United States of America

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH:

7  SOLE VOTING POWER
      0

8  SHARED VOTING POWER
      17,511,304

9  SOLE DISPOSITIVE POWER
      0

10 SHARED DISPOSITIVE POWER
      17,511,304

11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
      17,511,304

12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES     / /

13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
      6.03%

14 TYPE OF REPORTING PERSON
      IN





                                  SCHEDULE 13D

Item 1. Security and Issuer

     This  statement  relates  to the  Common  Stock,  par  value  $0.0005  (the
"Shares"),  issued by Biogen  Idec  Inc.  (the  "Issuer").  The  address  of the
principal  executive  offices of the Issuer is Biogen  Idec Inc.,  14  Cambridge
Center, Cambridge, Massachusetts 02142.

Item 2. Identity and Background

     The persons filing this statement are High River Limited Partnership ("High
River"), Hopper Investments LLC ("Hopper"),  Barberry Corp. ("Barberry"),  Icahn
Partners  Master  Fund LP ("Icahn  Master"),  Icahn  Partners  Master Fund II LP
("Icahn  Master II"),  Icahn  Partners  Master Fund III LP ("Icahn Master III"),
Icahn  Offshore LP ("Icahn  Offshore"),  Icahn  Partners LP ("Icahn  Partners"),
Icahn Onshore LP ("Icahn Onshore"),  Icahn Capital LP ("Icahn Capital"),  IPH GP
LLC ("IPH"),  Icahn Enterprises  Holdings L.P. ("Icahn  Enterprises  Holdings"),
Icahn Enterprises G.P. Inc. ("Icahn Enterprises GP"), Beckton Corp. ("Beckton"),
and Carl C. Icahn, a citizen of the United States of America (collectively,  the
"Reporting Persons").

     The principal business address of each of (i) High River, Hopper, Barberry,
Icahn  Offshore,  Icahn  Partners,  Icahn  Onshore,  Icahn  Capital,  IPH, Icahn
Enterprises  Holdings,  Icahn  Enterprises GP and Beckton is White Plains Plaza,
445 Hamilton  Avenue - Suite 1210,  White Plains,  NY 10601,  (ii) Icahn Master,
Icahn Master II and Icahn Master III is c/o Walkers SPV Limited, P.O. Box 908GT,
87 Mary Street,  George Town, Grand Cayman,  Cayman Islands, and (iii) Mr. Icahn
is c/o Icahn Associates Corp., 767 Fifth Avenue, 47th Floor, New York, NY 10153.

     Barberry is the sole member of Hopper, which is the general partner of High
River.  Icahn  Offshore is the general  partner of each of Icahn  Master,  Icahn
Master II and Icahn Master III.  Icahn  Onshore is the general  partner of Icahn
Partners.  Icahn  Capital is the general  partner of each of Icahn  Offshore and
Icahn Onshore.  Icahn  Enterprises  Holdings is the sole member of IPH, which is
the general partner of Icahn Capital.  Beckton is the sole  stockholder of Icahn
Enterprises GP, which is the general partner of Icahn Enterprises Holdings. Carl
C. Icahn is the sole  stockholder of each of Barberry and Beckton.  As such, Mr.
Icahn is in a  position  indirectly  to  determine  the  investment  and  voting
decisions made by each of the Reporting Persons.  In addition,  Mr. Icahn is the
indirect  holder  of  approximately  91% of  the  outstanding  depositary  units
representing  limited  partnership  interests in Icahn  Enterprises L.P. ("Icahn
Enterprises"). Icahn Enterprises GP is the general partner of Icahn Enterprises,
which is the sole limited partner of Icahn Enterprises Holdings.

     Each of High River and  Barberry is  primarily  engaged in the  business of
investing in securities.  Hopper is primarily engaged in the business of serving
as the general  partner of High River.  Each of Icahn  Master,  Icahn Master II,
Icahn  Master III and Icahn  Partners is  primarily  engaged in the  business of
investing in securities.  Icahn Offshore is primarily engaged in the business of
serving as the  general  partner of each of Icahn  Master,  Icahn  Master II and
Icahn Master III. Icahn Onshore is primarily  engaged in the business of serving
as the general partner of Icahn Partners.  Icahn Capital is primarily engaged in
the  business of serving as the general  partner of each of Icahn  Offshore  and
Icahn  Onshore.  IPH is  primarily  engaged  in the  business  of serving as the
general  partner of Icahn  Capital.  Icahn  Enterprises  Holdings  is  primarily
engaged in the  business  of holding  direct or  indirect  interests  in various
operating businesses.  Icahn Enterprises GP is primarily engaged in the business
of  serving  as the  general  partner  of each of Icahn  Enterprises  and  Icahn
Enterprises  Holdings.  Beckton is primarily  engaged in the business of holding
the capital stock of Icahn Enterprises GP.

     Carl C. Icahn's  present  principal  occupation or employment is serving as
(i) Chief  Executive  Officer of Icahn Capital LP, a wholly owned  subsidiary of
Icahn  Enterprises,  through which Mr. Icahn manages various private  investment
funds, including Icahn Partners,  Icahn Master, Icahn Master II and Icahn Master
III, (ii) Chairman of the Board of Icahn  Enterprises GP, the general partner of
Icahn Enterprises,  a New York Stock Exchange listed diversified holding company
engaged in a variety of businesses,  including  investment  management,  metals,
real estate and home fashion,  and (iii) Chairman of the Board and a director of
Starfire  Holding  Corporation  ("Starfire"),  a holding  company engaged in the
business of investing in and/or holding  securities of various entities,  and as
Chairman of the Board and a director of various of Starfire's subsidiaries.

     The name,  citizenship,  present  principal  occupation or  employment  and
business address of each director and executive officer of the Reporting Persons
are set forth in Schedule A attached hereto.

     None of the Reporting  Persons nor any manager or executive  officer of the
Reporting  Persons,  has,  during the past five years,  (a) been  convicted in a
criminal proceeding (excluding traffic violations or similar  misdemeanors),  or
(b) been a party to a civil proceeding of a judicial or  administrative  body of
competent jurisdiction and as a result of such proceeding was or is subject to a
judgment,  decree or final order enjoining future violations of, or prohibiting,
or  mandating  activities  subject  to,  Federal or State  securities  laws or a
finding of any violation with respect to such laws.

Item 3. Source and Amount of Funds or Other Consideration

     The Reporting  Persons  hold,  in the  aggregate,  17,511,304  Shares.  The
aggregate  purchase  price of the  Shares  purchased  by the  Reporting  Persons
collectively was $916,501,219 (including commissions). The source of funding for
the purchase of these Shares was the general  working  capital of the respective
purchasers.  The Shares  are held by the  Reporting  Persons in margin  accounts
together with other securities.  Such margin accounts may from time to time have
debit  balances.  Part of the  purchase  price of the  Shares  purchased  by the
Reporting Persons was obtained through margin borrowing. The Shares purchased by
the Reporting  Persons are maintained in margin accounts that include  positions
in  securities  in addition to Shares.  As of the close of business on August 8,
2008, the  indebtedness  of (i) High River's  margin  account was  approximately
$1,206,212,537,   (ii)  Icahn   Partners'   margin  account  was   approximately
$221,166,992,   (iii)  Icahn   Master's   margin   account   was   approximately
$391,343,830,   (iv)  Icahn  Master  II's  margin   account  was   approximately
$104,183,136,  and (v) Icahn  Master  III's  margin  account  was  approximately
$41,633,836.

Item 4. Purpose of Transaction

     The Reporting  Persons recently acquired Shares and further increased their
position in the belief that the Shares were undervalued.  Representatives of the
Reporting  Persons have had, and from time to time may seek to continue to have,
discussions  with  representatives  of the  Issuer to discuss  general  business
issues relating to the Issuer as well as their concerns  relating to shareholder
value.

     The  Reporting  Persons  may,  from time to time and at any  time,  acquire
additional Shares and/or other equity,  debt or other securities  (collectively,
"Securities")  of the Issuer in the open  market or  otherwise  and  reserve the
right  to  dispose  of any or all of their  Securities  in the  open  market  or
otherwise,  at any time and from time to time,  and to engage in any  hedging or
similar transactions with respect to the Securities.

Item 5. Interest in Securities of the Issuer

     (a) The  Reporting  Persons  may be  deemed  to  beneficially  own,  in the
aggregate,  17,511,304 Shares,  representing approximately 6.03% of the Issuer's
outstanding  Shares (based upon the 290,254,475  Shares stated to be outstanding
as of July 17,  2008 by the  Issuer in the  Issuer's  Form 10-Q  filed  with the
Securities  and Exchange  Commission on July 22, 2008 for the  quarterly  period
ended June 30, 2008).

     (b) High River has sole voting power and sole dispositive power with regard
to  3,502,261  Shares.  Each of  Hopper,  Barberry  and Carl C. Icahn has shared
voting  power and shared  dispositive  power with regard to such  Shares.  Icahn
Master has sole voting power and sole dispositive power with regard to 5,707,871
Shares. Each of Icahn Offshore,  Icahn Capital, IPH, Icahn Enterprises Holdings,
Icahn  Enterprises  GP, Beckton and Mr. Icahn has shared voting power and shared
dispositive  power with regard to such  Shares.  Icahn Master II has sole voting
power and sole dispositive power with regard to 1,956,501 Shares.  Each of Icahn
Offshore,  Icahn Capital, IPH, Icahn Enterprises Holdings, Icahn Enterprises GP,
Beckton and Mr. Icahn has shared voting power and shared  dispositive power with
regard  to such  Shares.  Icahn  Master  III has  sole  voting  power  and  sole
dispositive power with regard to 743,575 Shares.  Each of Icahn Offshore,  Icahn
Capital, IPH, Icahn Enterprises Holdings,  Icahn Enterprises GP, Beckton and Mr.
Icahn has shared voting power and shared  dispositive  power with regard to such
Shares.  Icahn  Partners has sole voting power and sole  dispositive  power with
regard to 5,601,096  Shares.  Each of Icahn Onshore,  Icahn Capital,  IPH, Icahn
Enterprises  Holdings,  Icahn  Enterprises  GP, Beckton and Mr. Icahn has shared
voting power and shared dispositive power with regard to such Shares.

     Each of Hopper, Barberry and Mr. Icahn, by virtue of their relationships to
High River (as  disclosed in Item 2), may be deemed to  indirectly  beneficially
own (as that term is defined in Rule 13d-3 under the Act) the Shares  which High
River  directly  beneficially  owns.  Each of  Hopper,  Barberry  and Mr.  Icahn
disclaims  beneficial  ownership of such Shares for all other purposes.  Each of
Icahn  Offshore,   Icahn  Capital,  IPH,  Icahn  Enterprises   Holdings,   Icahn
Enterprises GP, Beckton and Mr. Icahn, by virtue of their  relationships to each
of Icahn Master,  Icahn Master II and Icahn Master III (as disclosed in Item 2),
may be deemed to  indirectly  beneficially  own (as that term is defined in Rule
13d-3 under the Act) the Shares which each of Icahn Master,  Icahn Master II and
Icahn Master III  directly  beneficially  owns.  Each of Icahn  Offshore,  Icahn
Capital, IPH, Icahn Enterprises Holdings,  Icahn Enterprises GP, Beckton and Mr.
Icahn disclaims beneficial ownership of such Shares for all other purposes. Each
of  Icahn  Onshore,  Icahn  Capital,  IPH,  Icahn  Enterprises  Holdings,  Icahn
Enterprises GP, Beckton and Mr. Icahn, by virtue of their relationships to Icahn
Partners (as disclosed in Item 2), may be deemed to indirectly  beneficially own
(as that term is  defined in Rule 13d-3  under the Act) the Shares  which  Icahn
Partners directly beneficially owns. Each of Icahn Onshore,  Icahn Capital, IPH,
Icahn  Enterprises  Holdings,  Icahn  Enterprises  GP,  Beckton  and  Mr.  Icahn
disclaims beneficial ownership of such Shares for all other purposes.

     (c) The following table sets forth all transactions  with respect to Shares
effected during the past sixty (60) days by any of the Reporting Persons. Except
as  otherwise  noted  below,  all such  transactions  were  purchases  of Shares
effected in the open  market,  and the table  includes  commissions  paid in per
share prices.

Name of                  Date of           No. of  Shares     Purchase Price Per
Reporting Person         Transaction       Purchased          Share (U.S.$)
------------------- ------------------- ----------------- -------------------
High River              August 1, 2008           180,000              51.50
------------------- ------------------- ----------------- -------------------
High River              August 1, 2008           541,600              51.43
------------------- ------------------- ----------------- -------------------
High River              August 4, 2008           100,000              50.13
------------------- ------------------- ----------------- -------------------
High River              August 5, 2008             4,900              50.08
------------------- ------------------- ----------------- -------------------
High River              August 6, 2008            39,280              50.19
------------------- ------------------- ----------------- -------------------
High River              August 7, 2008            50,000              49.98
------------------- ------------------- ----------------- -------------------
High River              August 8, 2008             7,680              49.97
------------------- ------------------- ----------------- -------------------
High River             August 11, 2008               620              49.98
------------------- ------------------- ----------------- -------------------
High River             August 11, 2008            91,000              50.51
------------------- ------------------- ----------------- -------------------
Icahn Master            August 1, 2008           293,286              51.50
------------------- ------------------- ----------------- -------------------
Icahn Master            August 1, 2008           611,947              51.43
------------------- ------------------- ----------------- -------------------
Icahn Master            August 4, 2008           162,937              50.13
------------------- ------------------- ----------------- -------------------
Icahn Master            August 5, 2008             9,307              50.08
------------------- ------------------- ----------------- -------------------
Icahn Master            August 6, 2008            64,018              50.19
------------------- ------------------- ----------------- -------------------
Icahn Master            August 7, 2008            81,488              49.98
------------------- ------------------- -------------------------------------
Icahn Master            August 8, 2008            12,518              49.97
------------------- ------------------- -------------------------------------
Icahn Master           August 11, 2008             1,010              49.98
------------------- ------------------- -------------------------------------
Icahn Master           August 11, 2008           148,309              50.51
------------------- ------------------- -------------------------------------
Icahn Master II         August 1, 2008           100,573              51.50
------------------- ------------------- -------------------------------------
Icahn Master II         August 1, 2008           322,181              51.43
------------------- ------------------- -------------------------------------
Icahn Master II         August 4, 2008            55,873              50.13
------------------- ------------------- -------------------------------------
Icahn Master II         August 5, 2008             2,419              50.08
------------------- ------------------- -------------------------------------
Icahn Master II         August 6, 2008            21,943              50.19
------------------- ------------------- -------------------------------------
Icahn Master II         August 7, 2008            27,932              49.98
------------------- ------------------- -------------------------------------
Icahn Master II         August 8, 2008             4,291              49.97
------------------- ------------------- -------------------------------------
Icahn Master II        August 11, 2008               346              49.98
------------------- ------------------- -------------------------------------
Icahn Master II        August 11, 2008            50,836              50.51
------------------- ------------------- -------------------------------------
Icahn Master III        August 1, 2008            38,226              51.50
------------------- ------------------- -------------------------------------
Icahn Master III        August 1, 2008           123,869              51.43
------------------- ------------------- -------------------------------------
Icahn Master III        August 4, 2008            21,237              50.13
------------------- ---------------------------------------------------------
Icahn Master III        August 5, 2008               861              50.08
------------------- ------------------- -------------------------------------
Icahn Master III        August 6, 2008             8,340              50.19
------------------- ------------------- -------------------------------------
Icahn Master III        August 7, 2008            10,615              49.98
------------------- ------------------- -------------------------------------
Icahn Master III        August 8, 2008             1,629              49.97
------------------- ------------------- -------------------------------------
Icahn Master III       August 11, 2008               132              49.98
------------------- ------------------- -------------------------------------
Icahn Master III       August 11, 2008            19,321              50.51
------------------- ------------------- -------------------------------------
Icahn Partners          August 1, 2008           287,915              51.50
------------------- ------------------- -------------------------------------
Icahn Partners          August 1, 2008         1,108,403              51.43
------------------- ------------------- -------------------------------------
Icahn Partners          August 4, 2008           159,953              50.13
------------------- ------------------- -------------------------------------
Icahn Partners          August 5, 2008             7,013              50.08
------------------- ------------------- -------------------------------------
Icahn Partners          August 6, 2008            62,819              50.19
------------------- ------------------- -------------------- ----------------
Icahn Partners          August 7, 2008            79,965              49.98
------------------- ------------------- -------------------------------------
Icahn Partners          August 8, 2008            12,282              49.97
------------------- ------------------- -------------------------------------
Icahn Partners         August 11, 2008               992              49.98
------------------- ------------------- -------------------------------------
Icahn Partners         August 11, 2008           145,534              50.51
------------------- ------------------- -------------------------------------

Item 6. Contracts, Arrangements,  Understandings or Relationship with Respect to
        Securities of the Issuer

     Except as otherwise described herein, there are no contracts, arrangements,
understandings or relationships  (legal or otherwise) among the persons named in
Item 2 and between such persons and any person with respect to any securities of
the  Issuer,  including  but not  limited  to  transfer  or voting of any of the
securities,  finder's fees, joint ventures, loan or option arrangements, puts or
calls,  guarantees  of profits,  division  of profits or loss,  or the giving or
withholding of proxies.

Item 7. Material to be Filed as Exhibits

     1    Joint Filing Agreement of the Reporting Persons






                                    SIGNATURE

     After  reasonable  inquiry  and to the  best  of  each  of the  undersigned
knowledge and belief, each of the undersigned certifies that the information set
forth in this statement is true, complete and correct.

Dated: August 11, 2008

HIGH RIVER LIMITED PARTNERSHIP
         By: Hopper Investments LLC, general partner

         By:  /s/ Edward Mattner
              ------------------
         Name: Edward Mattner
         Title: Authorized Signatory

HOPPER INVESTMENTS LLC

         By:  /s/ Edward Mattner
              ------------------
         Name: Edward Mattner
         Title: Authorized Signatory

BARBERRY CORP.

         By:  /s/ Edward Mattner
              ------------------
         Name: Edward Mattner
         Title: Authorized Signatory

ICAHN PARTNERS MASTER FUND LP

         By:  /s/ Edward E. Mattner
              ---------------------
         Name: Edward E. Mattner
         Title: Authorized Signatory

ICAHN PARTNERS MASTER FUND II LP

         By:  /s/ Edward E. Mattner
              ---------------------
         Name: Edward E. Mattner
         Title: Authorized Signatory

ICAHN PARTNERS MASTER FUND III LP

         By:  /s/ Edward E. Mattner
              ---------------------
         Name: Edward E. Mattner
         Title: Authorized Signatory





ICAHN OFFSHORE LP

         By:  /s/ Edward E. Mattner
              ---------------------
         Name: Edward E. Mattner
         Title: Authorized Signatory

ICAHN PARTNERS LP

         By:  /s/ Edward E. Mattner
              ---------------------
         Name: Edward E. Mattner
         Title: Authorized Signatory

ICAHN ONSHORE LP

         By:  /s/ Edward E. Mattner
              ---------------------
         Name: Edward E. Mattner
         Title: Authorized Signatory

ICAHN CAPITAL LP
         By: IPH GP LLC, its general partner
         By: Icahn Enterprises Holdings L.P., its sole member
         By: Icahn Enterprises G.P. Inc., its general partner

         By:  /s/ Dominick Ragone
              -------------------
         Name: Dominick Ragone
         Title: Chief Financial Officer

IPH GP LLC
         By: Icahn Enterprises Holdings L.P., its sole member
         By: Icahn Enterprises G.P. Inc., its general partner

         By:  /s/ Dominick Ragone
              -------------------
         Name: Dominick Ragone
         Title: Chief Financial Officer

ICAHN ENTERPRISES HOLDINGS L.P.
         By: Icahn Enterprises G.P. Inc., its general partner

         By:  /s/ Dominick Ragone
              -------------------
         Name: Dominick Ragone
         Title: Chief Financial Officer






ICAHN ENTERPRISES G.P. INC.

By:  /s/ Dominick Ragone
     -------------------
         Name: Dominick Ragone
         Title: Chief Financial Officer

BECKTON CORP.

By:  /s/ Edward E. Mattner
     ---------------------
         Name: Edward E. Mattner
         Title: Authorized Signatory

/s/ Carl C. Icahn
-----------------
CARL C. ICAHN



               [Signature Page of Schedule 13D - Biogen Idec Inc.]






                                                                       EXHIBIT 1
                             JOINT FILING AGREEMENT

     In accordance with Rule  13d-1(k)(1)  under the Securities  Exchange Act of
1934, as amended, the persons named below agree to the joint filing on behalf of
each of them of a statement on Schedule 13D (including  amendments thereto) with
respect to the Common  Stock of Biogen  Idec Inc.  and  further  agree that this
Joint  Filing  Agreement  be  included as an Exhibit to such joint  filings.  In
evidence  thereof,  the undersigned,  being duly authorized,  have executed this
Joint Filing Agreement this 11th day of August, 2008.

HIGH RIVER LIMITED PARTNERSHIP
         By: Hopper Investments LLC, general partner

         By:      /s/ Edward Mattner
         ---------------------------
         Name: Edward Mattner
         Title: Authorized Signatory

HOPPER INVESTMENTS LLC


         By:      /s/ Edward Mattner
         ---------------------------
         Name: Edward Mattner
         Title: Authorized Signatory

BARBERRY CORP.

         By:      /s/ Edward Mattner
         ---------------------------
         Name: Edward Mattner
         Title: Authorized Signatory

ICAHN PARTNERS MASTER FUND LP

         By:      /s/ Edward E. Mattner
         ------------------------------
         Name: Edward E. Mattner
         Title: Authorized Signatory

ICAHN PARTNERS MASTER FUND II LP

         By:      /s/ Edward E. Mattner
         ------------------------------
         Name: Edward E. Mattner
         Title: Authorized Signatory

ICAHN PARTNERS MASTER FUND III LP

         By:      /s/ Edward E. Mattner
         ------------------------------
         Name: Edward E. Mattner
         Title: Authorized Signatory

ICAHN OFFSHORE LP

         By:      /s/ Edward E. Mattner
         ------------------------------
         Name: Edward E. Mattner
         Title: Authorized Signatory

ICAHN PARTNERS LP

         By:      /s/ Edward E. Mattner
         ------------------------------
         Name: Edward E. Mattner
         Title: Authorized Signatory

ICAHN ONSHORE LP

         By:      /s/ Edward E. Mattner
         ------------------------------
         Name: Edward E. Mattner
         Title: Authorized Signatory

ICAHN CAPITAL LP
         By: IPH GP LLC, its general partner
         By: Icahn Enterprises Holdings L.P., its sole member
         By: Icahn Enterprises G.P. Inc., its general partner

         By:      /s/ Dominick Ragone
         ----------------------------
         Name: Dominick Ragone
         Title: Chief Financial Officer

IPH GP LLC
         By: Icahn Enterprises Holdings L.P., its sole member
         By: Icahn Enterprises G.P. Inc., its general partner

         By:      /s/ Dominick Ragone
         ----------------------------
         Name: Dominick Ragone
         Title: Chief Financial Officer

ICAHN ENTERPRISES HOLDINGS L.P.
         By: Icahn Enterprises G.P. Inc., its general partner

         By:      /s/ Dominick Ragone
         ----------------------------
         Name: Dominick Ragone
         Title: Chief Financial Officer






ICAHN ENTERPRISES G.P. INC.

By:      /s/ Dominick Ragone
----------------------------
         Name: Dominick Ragone
         Title: Chief Financial Officer

BECKTON CORP.

By:      /s/ Edward E. Mattner
------------------------------
         Name: Edward E. Mattner
         Title: Authorized Signatory

/s/ Carl C. Icahn
-----------------
CARL C. ICAHN







  [Signature Page of Joint Filing Agreement to Schedule 13D - Biogen Idec Inc.]





SCHEDULE A

            DIRECTORS AND EXECUTIVE OFFICERS OF THE REPORTING PERSONS

     The following sets forth the name,  position,  and principal  occupation of
each director and executive officer of each of the Reporting Persons.  Each such
person  is a  citizen  of the  United  States of  America.  Except as  otherwise
indicated,  the  business  address  of each  director  and  officer is c/o Icahn
Associates Corp., 767 Fifth Avenue, 47th Floor, New York, New York 10153. To the
best of the Reporting Persons' knowledge,  except as set forth in this statement
on Schedule 13D,  none of the  directors or executive  officers of the Reporting
Persons own any Shares.

HIGH RIVER LIMITED PARTNERSHIP
Name                                Position
----                                --------
Hopper Investments LLC              General Partner


HOPPER INVESTMENTS LLC
Name                                Position
----                                --------
Edward E. Mattner                   Authorized Signatory


BARBERRY CORP.
Name                                Position
----                                --------
Carl C. Icahn                       Chairman of the Board; President
Jordan Bleznick                     Vice President/Taxes
Edward E. Mattner                   Vice President; Authorized Signatory
Gail Golden                         Vice President; Authorized Signatory
Vincent J. Intrieri                 Vice President; Authorized Signatory
Keith Cozza                         Secretary; Treasurer
Irene March                         Authorized Signatory


ICAHN PARTNERS MASTER FUND LP
ICAHN PARTNERS MASTER FUND II LP
ICAHN PARTNERS MASTER FUND III LP
Name                                Position
----                                --------
Icahn Offshore LP                   General Partner
Carl Icahn                          Chief Executive Officer
Keith A. Meister                    Managing Director
Vincent J. Intrieri                 Managing Director
Rupal Doshi                         Chief Operating Officer
Irene March                         Chief Financial Officer
Edward E. Mattner                   Authorized Signatory
Gail Golden                         Authorized Signatory
Dana Witkin                         Director of Investor Relations
Keith Cozza                         Chief Compliance Officer
Anthony Canova                      Controller


ICAHN PARTNERS LP
Name                                Position
----                                --------
Icahn Onshore LP                    General Partner
Carl Icahn                          Chief Executive Officer
Keith A. Meister                    Managing Director
Vincent J. Intrieri                 Managing Director
Rupal Doshi                         Chief Operating Officer
Irene March                         Chief Financial Officer
Edward E. Mattner                   Authorized Signatory
Gail Golden                         Authorized Signatory
Dana Witkin                         Director of Investor Relations
Keith Cozza                         Chief Compliance Officer
Anthony Canova                      Controller


ICAHN ONSHORE LP
ICAHN OFFSHORE LP

Name                                Position
----                                --------
Icahn Capital LP                    General Partner
Carl Icahn                          Chief Executive Officer
Keith A. Meister                    Managing Director
Vincent J. Intrieri                 Managing Director
Rupal Doshi                         Chief Operating Officer
Irene March                         Chief Financial Officer
Edward E. Mattner                   Authorized Signatory
Gail Golden                         Authorized Signatory
Dana Witkin                         Director of Investor Relations
Keith Cozza                         Chief Compliance Officer
Anthony Canova                      Controller


ICAHN CAPITAL LP
Name                                Position
----                                --------
IPH GP LLC                          General Partner


IPH GP LLC
Name                                Position
----                                --------
Icahn Enterprises                   Sole Member
Holdings L.P.


ICAHN ENTERPRISES HOLDINGS L.P.
Name                                Position
----                                --------
Icahn Enterprises                   General Partner
G.P. Inc.


ICAHN ENTERPRISES G.P. INC.
Name                                Position
----                                --------
Carl C. Icahn                       Chairman
Keith A. Meister                    Vice Chairman; Principal Executive Officer
William A. Leidesdorf               Director
Jack G. Wasserman                   Director
James L. Nelson                     Director
Vincent J. Intrieri                 Director
Peter K. Shea                       President
Dominick Ragone                     Chief Financial Officer
Andrew Skobe                        Treasurer
John P. Saldarelli                  Vice President; Secretary
Felicia P. Buebel                   Assistant Secretary
Craig Petit                         Vice President/Taxes


BECKTON CORP.
Name                                Position
----                                --------
Carl C. Icahn                       Chairman of the Board; President
Jordan Bleznick                     Vice President/Taxes
Edward E. Mattner                   Authorized Signatory
Keith Cozza                         Secretary; Treasurer