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 *
Myres Albert H.
  2. Issuer Name and Ticker or Trading Symbol
GenOn Energy, Inc. [GEN]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
SVP, Govmt & Public Affairs
(Last)
(First)
(Middle)
1000 MAIN STREET, 12TH FLOOR
3. Date of Earliest Transaction (Month/Day/Year)
12/03/2010
(Street)

HOUSTON, TX 77002
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 12/03/2010   F   22,091 (1) D $ 3.515 34,132 (2) 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
Time-Based Cash Units (3) 12/03/2010   M     20,000   (3)   (3) Common Stock 20,000 $ 0 0 D  
Performance-Based Cash Units (4) 12/03/2010   M     8,391   (4)   (4) Common Stock 8,391 $ 0 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Myres Albert H.
1000 MAIN STREET
12TH FLOOR
HOUSTON, TX 77002
      SVP, Govmt & Public Affairs  

Signatures

 /s/ Albert H. Myres   12/07/2010
**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 reporting person disposed of these shares to satisfy tax withholding obligations related to the vesting of restricted stock units in connection with the merger (the "Merger") involving Mirant Corporation and GenOn Energy, Inc., formerly known as RRI Energy, Inc.
(2) Includes 1,571 shares acquired under the RRI Energy, Inc. Employee Stock Purchase Plan since the reporting person's last report.
(3) Each time-based cash unit is the economic equivalent of one share of common stock of GenOn Energy, Inc. The time-based cash units were paid in cash in connection with the Merger based on the fair market value per share of GenOn Energy, Inc. common stock on the date immediately preceding the closing date of the Merger.
(4) Each performance-based cash unit is the economic equivalent of one share of common stock of GenOn Energy, Inc. The performance-based cash units were paid in cash in connection with the Merger based on the fair market value per share of GenOn Energy, Inc. common stock on the date immediately preceding the closing date of the Merger.

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.