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 * CASON THOMAS W   2. Issuer Name and Ticker or Trading Symbol MIRANT CORP [MIR] 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) 1155 PERIMETER CENTER WEST 3. Date of Earliest Transaction (Month/Day/Year) 12/03/2010 (Street) ATLANTA, GA 30338 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   D   18,272 D (1) 0 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

Stock Option

$ 45.77

12/03/2010

D

1,821

(2)

05/15/2012

Common Stock

1,821

(2)

0

D

Stock Option

$ 24.37

12/03/2010

D

5,129

(3)

05/10/2016

Common Stock

5,129

(3)

0

D

Stock Option

$ 24.64

12/03/2010

D

5,073

(4)

01/13/2016

Common Stock

5,073

(4)

0

D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
CASON THOMAS W 1155 PERIMETER CENTER WEST ATLANTA, GA 30338	X

Signatures

/s/ David E. Howard, Attorney-in-Fact		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)	Disposed of pursuant to merger agreement between issuer, RRI Energy Holdings, Inc., and RRI Energy, Inc. ("RRI") in exchange for 51,801 shares of RRI common stock having a market value of $3.62 per share on the effective date of the merger plus cash consideration for a fractional share of RRI common stock.
(2)	Upon completion of the merger, this fully-vested option was converted into an option to purchase 5,162 shares of RRI common stock at $16.15 per share. The reporting person also received cash consideration for that portion of the option relating to a fractional share of RRI common stock.
(3)	Upon completion of the merger, this fully-vested option was converted into an option to purchase 14,540 shares of RRI common stock at $8.60 per share. The reporting person also received cash consideration for that portion of the option relating to a fractional share of RRI common stock.
(4)	Upon completion of the merger, this fully-vested option was converted into an option to purchase 14,381 shares of RRI common stock at $8.70 per share. The reporting person also received cash consideration for that portion of the option relating to a fractional share of RRI common stock.

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.