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 *
OEP AC Holdings, LLC
  2. Issuer Name and Ticker or Trading Symbol
ARTHROCARE CORP [ARTC]
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)
C/O ONE EQUITY PARTNERS, 320 PARK AVENUE, 18TH FLOOR
3. Date of Earliest Transaction (Month/Day/Year)
05/24/2012
(Street)

NEW YORK, NY 10022
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
Restricted Stock Units (1) 05/24/2012   A   8,624     (2)   (2) Common Stock 8,624 $ 0 8,624 I (3) (4) By One Equity Partners III, L.P. See Footnote (3) (4)

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
OEP AC Holdings, LLC
C/O ONE EQUITY PARTNERS
320 PARK AVENUE, 18TH FLOOR
NEW YORK, NY 10022
    X    
One Equity Partners III, L.P.
320 PARK AVENUE
18TH FLOOR
NEW YORK, NY 10022
    X    
OEP General Partner III, L.P.
320 PARK AVENUE
18TH FLOOR
NEW YORK, NY 10022
    X    
OEP Parent LLC
320 PARK AVENUE, 18TH FLOOR
NEW YORK, NY 10022
    X    

Signatures

 /s/ Christian P. Ahrens Vice-President & Treasurer of OEP AC Holdings, LLC   05/29/2012
**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) Each restricted stock unit represents a contingent right to receive one share of ArthoCare Corporation (the "Issuer") common stock.
(2) The restricted stock units vest over a three year period, with an initial 33.33% of such award vesting on May 24, 2013 (the "Initial Vesting Date") and 33.33% of such award vesting on each of the successive two anniversaries of the Initial Vesting Date. Vested restricted stock units will be delivered to Messrs. Belinfanti and Ahrens upon their respective retirements.
(3) Each of Mr. Gregory A. Belinfanti and Mr. Christian P. Ahrens serves as a director of the Issuer and as an officer of OEP AC Holdings, LLC, a Delaware limited liability company ("OEP"). The managing member of OEP is One Equity Partners III, L.P., a Cayman Islands limited partnership ("OEP III"), of which the sole general partner is OEP General Partner III, L.P., a Cayman Islands limited partnership ("OEP GP III"), of which the sole general partner is OEP Parent LLC, a Delaware limited liability company ("OEP Parent"), of which the sole member is OEP Holding Corporation, a Delaware corporation ("OEP Holding") of which the sole stockholder is JPMorgan Capital Corporation, a Delaware corporation ("JPM CC"), of which the sole stockholder is Banc One Financial LLC, a Delaware limited liability company ("BOF LLC"), of which the sole member is JPMorgan Chase & Co., a Delaware corporation.
(4) The reported shares consist of (i) 4,312 restricted stock units granted to Mr. Belinfanti and held by him on behalf of OEP III and (ii) 4,312 restricted stock units granted to Mr. Ahrens and held by him on behalf of OEP III, pursuant to the Issuer's Amended and Restated 2003 Incentive Stock Plan in consideration of Mr. Belinfanti's and Mr. Ahrens' service on the Board of Directors of the Issuer.
 
Remarks:
Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein except to the extent of its pecuniary interest therein. Exhibit List Exhibit 99 - Joint Filer Information

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