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 *
BAKER FELIX
  2. Issuer Name and Ticker or Trading Symbol
ACADIA PHARMACEUTICALS INC [ACAD]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
667 MADISON AVENUE, 21ST FLOOR
3. Date of Earliest Transaction (Month/Day/Year)
01/18/2013
(Street)

NEW YORK, NY US 10065
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

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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
Stock Options (right to buy) $ 5.22 01/18/2013   A   15,000     (1) 01/17/2023 Common Stock 15,000 $ 0 15,000 I See footnote (1) (2)

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
BAKER FELIX
667 MADISON AVENUE, 21ST FLOOR
NEW YORK, NY US 10065
  X   X    
BAKER JULIAN
667 MADISON AVENUE, 21ST FLOOR
NEW YORK, NY US 10065
  X   X    
BAKER BROS ADVISORS LLC
667 MADISON AVENUE, 21ST FLOOR
NEW YORK, NY US 10065
  X   X    
667, L.P.
667 MADISON AVENUE 21ST FLOOR
NEW YORK, NY US 10065
  X   X    
14159, L.P.
667 MADISION AVENUE, 21ST FLOOR
NEW YORK, NY US 10065
  X   X    
Baker Brothers Life Sciences LP
667 MADISON AVENUE, 21ST FLOOR
NEW YORK, NY US 10065
  X   X    

Signatures

 /s/ Felix J. Baker   01/23/2013
**Signature of Reporting Person Date

 /s/ Julian C. Baker   01/23/2013
**Signature of Reporting Person Date

 Title: President /s/ Scott L. Lessing   01/23/2013
**Signature of Reporting Person Date

 Baker Bros. Advisors, LLC, Mgmt. Co. and Inv. Adviser to 667, L.P., pursuant to authority granted by Baker Biotech Capital, L.P., GP to 667, L.P. Name: Scott L. Lessing, Title: President /s/ Scott L. Lessing   01/23/2013
**Signature of Reporting Person Date

 Baker Bros. Advisors, LLC, Mgmt. Co. and Inv. Adviser to 14159, L.P., pursuant to authority granted by 14159 Capital, L.P., GP to 14159, L.P. Name: Scott L. Lessing, Title: President /s/ Scott L. Lessing   01/23/2013
**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) On January 18, 2013, Dr. Stephen R. Biggar was elected to ACADIA Pharmaceuticals Inc.'s (the "Issuer") Board of Directors (the "Board"). Upon his appointment to the Board, Dr. Biggar was granted options to purchase 15,000 shares of the Issuer's common stock at $5.22 per share expiring 10 years from the date of the grant (the "Options"). The Options vest in equal tranches on January 18, 2014 and January 18, 2015. Dr. Biggar serves on the Issuer's Board as a representative of Baker Brothers Life Sciences, L.P., ("Life Sciences"), 667, L.P. ("667"), and 14159, L.P. ("14159" and together with Life Sciences and 667, the "Funds"). Due to the agreements and policies of the Funds and Dr. Biggar's agreement to follow those agreements and policies, Dr. Biggar does not have any right to receive pecuniary interest in securities as compensation for serving as a director of the Issuer and therefore has no pecuniary interest in the Options. Dr. Biggar, however, retains the right to vote and dispose of any shares of common stock underlying the Options. The Funds are entitled to pecuniary interest in the Options and each holds an indirect proportionate pecuniary interest. Felix J. Baker and Julian C. Baker, solely as a result of their ownership interest in the general partner of the general partners of the Funds, may be deemed to have an indirect proportionate pecuniary interest in the Options (ie. no direct pecuniary interest).
(2) Baker Bros. Advisors, LLC (the "Adviser") serves as the Investment Adviser to the Funds. In connection with the services provided by the Adviser, the Adviser receives an asset-based management fee that does not confer any pecuniary interest in the securities held by the Funds. Julian C. Baker and Felix J. Baker are principals of the Adviser. The Adviser has complete and unlimited discretion and authority with respect to the investment and voting power of the securities held by the Funds. The general partners of the Funds relinquished to the Adviser all discretion and authority with respect to the investment and voting power of the securities held by the Funds. Julian C. Baker, Felix J. Baker and the Adviser disclaim beneficial ownership of the securities held directly by the Funds except to the extent of their pecuniary interest therein, and this report shall not be deemed an admission that any of Julian C. Baker, Felix J. Baker or the Adviser is a beneficial owner of such securities for purposes of Section 16 or any other purpose.
 
Remarks:
Dr. Stephen R. Biggar is a Partner of Baker Bros. Advisors LLC and a director of ACADIA Pharmaceuticals, Inc. For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, the reporting persons are deemed directors by deputization by virtue of their representation on the Board of Directors of ACADIA Pharmaceuticals. Inc.

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