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
OMB APPROVAL
OMB Number: 3235-0287
Expires: January 31, 2005
Estimated average burden hours per response... 0.5

(Print or Type Responses)
1. Name and Address of Reporting Person *
EVNIN LUKE
  2. Issuer Name and Ticker or Trading Symbol
Pacira Pharmaceuticals, Inc. [PCRX]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
C/O MPM ASSET MANAGEMENT, 200 CLARENDON STREET, 54TH FLOOR
3. Date of Earliest Transaction (Month/Day/Year)
04/12/2013
(Street)

BOSTON, MA 02116
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ 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 04/12/2013   X   37,192 (1) A $ 2.69 1,317,671 I See Footnote (2) (3)
Common Stock 04/12/2013   S(4)   3,416 (4) D $ 29.3 1,314,255 I See Footnote (3) (5)
Common Stock               22,746 D  

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number. SEC 1474 (9-02)

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
Common Stock Warrants (Right to Buy) $ 2.69 04/12/2013   X     37,192 (1) 01/22/2009 01/21/2014 Common Stock 37,192 $ 0 0 I See Footnote (1)

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
EVNIN LUKE
C/O MPM ASSET MANAGEMENT
200 CLARENDON STREET, 54TH FLOOR
BOSTON, MA 02116
  X      

Signatures

 /s/ Luke Evnin   05/08/2013
**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) The warrants were held and exercised as follows: 34,858 by MPM BioVentures IV-QP, L.P. ("BV IV QP"), 1,343 by MPM BioVentures IV GmbH & Co. Beteiligungs KG ("BV IV KG") and 991 by MPM Asset Management Investors BV4 LLC ("AM BV4"). MPM BioVentures IV GP LLC and MPM BioVentures IV LLC ("BV LLC") are the direct and indirect general partners of BV IV QP and BV IV KG and BV LLC is the manager of AM BV4. The Reporting Person is a member of BV LLC.
(2) The shares are held as follows: 1,234,997 by BV IV QP, 47,582 by BV IV KG and 35,092 by AM BV4. The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein.
(3) Does not reflect previously reported transactions that occurred after April 12, 2013 and the Form 4s filed by the Reporting Person reporting such transactions failed to take into account the transactions reported hereby. Accordingly, the Form 4s filed by the Reporting Person on April 18, 2013 and April 29, 2013 understated the number of shares beneficially owned following the transactions reported therein by an aggregate of 33,776 shares.
(4) On April 12, 2013, the following warrants to purchase shares of PCRX common stock were exercised for $2.69 per share: 34,858 by BV IV QP, 1,343 by BV IV KG and 991 by AM BV4. The exercise price was paid on a cashless basis, resulting in PCRX's withholding of the following warrant shares to pay the exercise price: 3,201 for BV IV QP, 124 for BV IV KG and 91 for AM BV4.
(5) The shares are held as follows: 1,231,796 by BV IV QP, 47,458 by BV IV KG and 35,001 by AM BV4. The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein.

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.