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 *
STACK DAVID M
  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
__X__ Officer (give title below) _____ Other (specify below)
CEO and Chairman
(Last)
(First)
(Middle)
C/O PACIRA PHARMACEUTICALS, INC., 5 SYLVAN WAY, SUITE 300
3. Date of Earliest Transaction (Month/Day/Year)
06/13/2018
(Street)

PARSIPPANY, NJ 07054
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 06/13/2018   A   28,375 (1) A $ 0 110,415 D  
Common Stock               18,596 I By Stack Schroon Mohawk FLP (2)
Common Stock               1,208 I By LCK Investment LLC (2)

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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 Option (Right to Buy) $ 38.35 06/13/2018   A   170,250     (3) 06/13/2028 Common Stock 170,250 $ 0 170,250 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
STACK DAVID M
C/O PACIRA PHARMACEUTICALS, INC.
5 SYLVAN WAY, SUITE 300
PARSIPPANY, NJ 07054
  X     CEO and Chairman  

Signatures

 /s/ Kristen Williams, Attorney-in-Fact   06/15/2018
**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) Represents restricted stock units that vest in four equal annual installments beginning on June 3, 2019, provided that the reporting person remains in continuous service with the issuer as of each vesting date. Each restricted stock unit represents the contingent right to receive one share of the issuer's common stock.
(2) Mr. Stack is the general partner of Stack Schroon Mohawk FLP. Mr. Stack and his wife are the owners of LCK Investment LLC.
(3) The stock option vests and becomes exercisable as to 25% of the option shares on the first anniversary of the grant date, and vests as to the remaining shares in successive equal quarterly installments over the subsequent three years, provided that the reporting person remains in continuous service with the issuer as of each vesting date.

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