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 *
INVESTOR AB
   2. Issuer Name and Ticker or Trading Symbol
ACHILLION PHARMACEUTICALS INC [ACHN] 		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)
ARSENALSGATAN 8C S-103, 		 3. Date of Earliest Transaction (Month/Day/Year)
12/08/2008
(Street)

STOCKHOLM, V7 		 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 (1) 12/08/2008   P   25,000 A $ 1.01 2,573,360 I See Footnote (1)
Common Stock (2) 12/09/2008   P   50,000 A $ 1 2,623,360 I See Footnote (2)
Common Stock (3) 12/08/2008   P   17,500 A $ 1.01 1,801,362 D  
Common Stock (3) 12/09/2008   P   35,000 A $ 1 1,836,362 D  

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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
INVESTOR AB
ARSENALSGATAN 8C S-103
STOCKHOLM, V7 		     X    
INVESTOR GROWTH CAPITAL LTD
CANADA COURT
UPLAND ROAD, ST. PETER PORT
GUERNSEY, CHANNEL ISLANDS, X0 GY1 3BQ		     X    

Signatures

 /s/ Michael Oporto   12/10/2008
**Signature of Reporting Person Date
 /s/ Henry Gooss   12/10/2008
**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) 17,500 shares of Common Stock, par value $0.001 (the "Common Stock"), were acquired by Investor Growth Capital Limited and 7,500 shares of Common Stock were acquired by Investor Group, L.P. The shares of Common Stock reported in Column 5 are held directly by Investor Growth Capital Limited and Investor Group, L.P. Investor Growth Capital Limited is an indirect wholly-owned subsidiary of Investor AB. Investor Group, L.P. is a limited partnership of which Investor AB is the indirect general partner. Investor AB may be deemed to beneficially own the securities held by Investor Growth Capital Limited and Investor Group, L.P. Investor AB disclaims beneficial ownership of such securities except to the extent of its pecuniary interest in such securities.
(2) 35,000 shares of Common Stock were acquired by Investor Growth Capital Limited and 15,000 shares of Common Stock were acquired by Investor Group, L.P. The shares of Common Stock reported in Column 5 are held directly by Investor Growth Capital Limited and Investor Group, L.P. Investor Growth Capital Limited is an indirect wholly-owned subsidiary of Investor AB. Investor Group, L.P. is a limited partnership of which Investor AB is the indirect general partner. Investor AB may be deemed to beneficially own the securities held by Investor Growth Capital Limited and Investor Group, L.P. Investor AB disclaims beneficial ownership of such securities except to the extent of its pecuniary interest in such securities.
(3) These shares of Common Stock are held directly by Investor Growth Capital Limited.

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