SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
X	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* MPM BioVentures IV QP LP (Last) (First) (Middle) C/O MPM ASSET MANAGEMENT 200 CLARENDON STREET, 54TH FLOOR (Street) BOSTON MA 02116 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol Pacira Pharmaceuticals, Inc. [ PCRX ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director 10% Owner Officer (give title below) X Other (specify below) Former 10% Owner
	3. Date of Earliest Transaction (Month/Day/Year) 03/11/2013
	4. If Amendment, Date of 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

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	03/11/2013		S		500,000(1)	D	$27.86	2,790,479	I	See Footnote(2)

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 Securities Underlying Derivative Security (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: 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

1. Name and Address of Reporting Person* MPM BioVentures IV QP LP (Last) (First) (Middle) C/O MPM ASSET MANAGEMENT 200 CLARENDON STREET, 54TH FLOOR (Street) BOSTON MA 02116 (City) (State) (Zip)

1. Name and Address of Reporting Person* Scopa James Paul (Last) (First) (Middle) C/O MPM ASSET MANAGEMENT 601 GATEWAY BLVD., SUITE 350 (Street) SOUTH SAN FRANCISCO CA 94080 (City) (State) (Zip)

1. Name and Address of Reporting Person* MPM BioVentures IV GP LLC (Last) (First) (Middle) C/O MPM ASSET MANAGEMENT 200 CLARENDON STREET, 54TH FLOOR (Street) BOSTON MA 02116 (City) (State) (Zip)

1. Name and Address of Reporting Person* MPM BioVentures IV LLC (Last) (First) (Middle) C/O MPM ASSET MANAGEMENT 200 CLARENDON STREET, 54TH FLOOR (Street) BOSTON MA 02116 (City) (State) (Zip)

1. Name and Address of Reporting Person* MPM Asset Management Investors BV4 LLC (Last) (First) (Middle) C/O MPM ASSET MANAGEMENT 200 CLARENDON STREET, 54TH FLOOR (Street) BOSTON MA 02116 (City) (State) (Zip)

1. Name and Address of Reporting Person* MPM BioVentures IV GmbH & Co. Beteiligungs KG (Last) (First) (Middle) C/O MPM ASSET MANAGEMENT 200 CLARENDON STREET, 54TH FLOOR (Street) BOSTON MA 02116 (City) (State) (Zip)

1. Name and Address of Reporting Person* Foley Todd (Last) (First) (Middle) C/O MPM ASSET MANAGEMENT 200 CLARENDON STREET, 54TH FLOOR (Street) BOSTON MA 02116 (City) (State) (Zip)

1. Name and Address of Reporting Person* Vander Vort John (Last) (First) (Middle) C/O MPM ASSET MANAGEMENT 200 CLARENDON STREET, 54TH FLOOR (Street) BOSTON MA 02116 (City) (State) (Zip)

Explanation of Responses:

1. The shares were sold as follows: 468,621 by MPM BioVentures IV-QP, L.P. ("BV IV QP"), 18,054 by MPM BioVentures IV GmbH & Co. Beteiligungs KG ("BV IV KG") and 13,325 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. Vaughn M. Kailian, Ansbert Gadicke, Luke Evnin, James Paul Scopa, Todd Foley and John Vander Vort are the members of BV LLC.

2. The shares are held as follows: 2,615,352 by BV IV QP, 100,758 by BV IV KG and 74,369 by AM BV4. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of his, her or its respective pecuniary interest therein.

Remarks:

See Form 4 for Vaughn M. Kailian for additional members of this joint filing.

	By Vaughn Kailian, member of MPM BioVentures IV LLC, the managing member of MPM BioVentures IV GP LLC, the general partner of MPM BioVentures IV-QP, L.P. /s/ Vaughn Kailian	03/13/2013
	/s/ James Paul Scopa	03/13/2013
	By Vaughn Kailian, member of MPM BioVentures IV LLC, the managing member of MPM BioVentures IV GP LLC /s/ Vaughn Kailian	03/13/2013
	By Vaughn Kailian, member of MPM BioVentures IV LLC /s/ Vaughn Kailian	03/13/2013
	By Vaughn Kailian, member of MPM BioVentures IV LLC, the manager of MPM Asset Management Investors BV4 LLC /s/ Vaughn Kailian	03/13/2013
	By Vaughn Kailian, member of MPM BioVentures IV LLC, the managing member of MPM BioVentures IV GP LLC, the managing limited partner of MPM BioVentures IV GmbH & Co. Beteiligungs KG /s/ Vaughn Kailian	03/13/2013
	/s/ Todd Foley	03/13/2013
	/s/ John Vander Vort	03/13/2013
	** Signature of Reporting Person	Date
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