Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
ATLAS VENTURE FUND V LP
  2. Issuer Name and Ticker or Trading Symbol
ALNYLAM PHARMACEUTICALS, INC. [ALNY]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
890 WINTER STREET, SUITE 320
3. Date of Earliest Transaction (Month/Day/Year)
02/23/2006
(Street)

WALTHAM, MA 02451
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
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 02/23/2006   S   9,960 D $ 15.1416 0 D (1)  
Common Stock 02/24/2006   S   18,971 D $ 14.797 393,956 D (1)  
Common Stock 02/23/2006   S   2,474 D $ 15.1416 0 D (2)  
Common Stock 02/24/2006   S   4,713 D $ 14.797 97,871 D (2)  
Common Stock 02/23/2006   S   166 D $ 15.1416 0 D (3)  
Common Stock 02/24/2006   S   316 D $ 14.797 6,557 D (3)  
Common Stock 02/23/2006   S   18,081 D $ 15.1416 0 D (4)  
Common Stock 02/24/2006   S   34,439 D $ 14.797 715,171 D (4)  
Common Stock 02/23/2006   S   488 D $ 15.1416 0 D (5)  
Common Stock 02/24/2006   S   930 D $ 14.797 19,314 D (5)  
Common Stock 02/23/2006   S   331 D $ 15.1416 0 D (6)  
Common Stock 02/24/2006   S   631 D $ 14.797 13,095 D (6)  
Common Stock 02/23/2006   S   12,600 D $ 15.1416 0 I See Footnote (7)
Common Stock 02/24/2006   S   24,000 D $ 14.797 498,384 I See Footnote (7)
Common Stock 02/23/2006   S   18,900 D $ 15.1416 0 I See Footnote (8)
Common Stock 02/24/2006   S   36,000 D $ 14.797 747,580 I See Footnote (8)

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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 Underlying Securities
(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 of Derivative Security: 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

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
ATLAS VENTURE FUND V LP
890 WINTER STREET
SUITE 320
WALTHAM, MA 02451
    X    
ATLAS VENTURE PARALLEL FUND V-A C V
890 WINTER STREET
SUITE 320
WALTHAM, MA 02451
    X    
ATLAS VENTURE ENTREPRENEURS FUND V LP
890 WINTER STREET
SUITE 320
WALTHAM, MA 02451
    X    
ATLAS VENTURE FUND VI LP
890 WINTER STREET
SUITE 320
WALTHAM, MA 02451
    X    
Atlas Venture Fund VI GmbH & Co KG
890 WINTER STREET
SUITE 320
WALTHAM, MA 02451
    X    
ATLAS VENTURE ENTREPRENEURS FUND VI LP
890 WINTER STREET
SUITE 320
WALTHAM, MA 02451
    X    
ATLAS VENTURE ASSOCIATES V LP
890 WINTER STREET
SUITE 320
WALTHAM, MA 02451
    X    
Atlas Venture Associates VI, L.P.
890 WINTER STREET
SUITE 320
WALTHAM, MA 02451
    X    

Signatures

 Atlas Venture Fund V, L.P.   02/27/2006
**Signature of Reporting Person Date

 Atlas Venture Parallel Fund V-A, C.V.   02/27/2006
**Signature of Reporting Person Date

 Atlas Venture Entrepreneurs' Fund V, L.P.   02/27/2006
**Signature of Reporting Person Date

 Atlas Venture Fund VI, L.P.   02/27/2006
**Signature of Reporting Person Date

 Atlas Venture Fund VI GmbH & Co. KG   02/27/2006
**Signature of Reporting Person Date

 Atlas Venture Entrepreneurs' Fund VI, L.P.   02/27/2006
**Signature of Reporting Person Date

 Atlas Venture Associates V, L.P.   02/27/2006
**Signature of Reporting Person Date

 Atlas Venture Associates VI, L.P.   02/27/2006
**Signature of Reporting Person Date

 /s/ Jeanne Larkin Henry (Vice-President)   02/27/2006
**Signature of Reporting Person Date

Explanation of Responses:

* 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).
(1) Sale of shares of the Issuer's Common Stock by Atlas Venture Fund V, L.P. These shares are owned directly by Atlas Venture Fund V, L.P.
(2) Sale of shares of the Issuer's Common Stock by Atlas Venture Parallel Fund V-A, C.V. These shares are owned directly by Atlas Venture Parallel Fund V-A, C.V.
(3) Sale of shares of the Issuer's Common Stock by Atlas Venture Entrepreneurs' Fund V, L.P. These shares are owned directly by Atlas Venture Entrepreneurs' Fund V, L.P.
(4) Sale of shares of the Issuer's Common Stock by Atlas Venture Fund VI, L.P. These shares are owned directly by Atlas Venture Fund VI, L.P.
(5) Sale of shares of the Issuer's Common Stock by Atlas Venture Entrepreneurs' Fund VI, L.P. These shares are owned directly by Atlas Venture Entrepreneurs' Fund VI, L.P.
(6) Sale of shares of the Issuer's Common Stock by Atlas Venture Fund VI GmbH & Co. KG. These shares are owned directly by Atlas Venture Fund VI GmbH & Co. KG.
(7) Sale of shares of the Issuer's Common Stock by Atlas Venture Fund V, L.P., Atlas Venture Parallel Fund V-A, C.V. and Atlas Venture Entrepreneurs' Fund V, L.P. These shares are owned directly by Atlas Venture Fund V, L.P., Atlas Venture Paraellel Fund V-A, C.V. and Atlas Venture Entrepreneurs' Fund V, L.P. Atlas Venture Associates V, L.P. disclaims beneficial ownership as to such shares except to the extent of its proportionate pecuniary interest therein.
(8) Sale of shares of the Issuer's Common Stock by Atlas Venture Fund VI, L.P., Atlas Venture Fund VI GmbH & Co. KG and Atlas Venture Entrepreneurs' Fund VI, L.P. These shares are owned directly by Atlas Venture Fund VI, L.P., Atlas Venture Fund VI GmbH & Co. KG and Atlas Venture Entrepreneurs' Fund VI, L.P. Atlas Venture Associates VI, L.P. disclaims beneficial ownership as to such shares except to the extent of its proportionate pecuniary interest therein.

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