UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   FORM 12b-25

                           NOTIFICATION OF LATE FILING

                          SEC File Number: 001 - 16107

 (Check one) [ ]Form 10-K [ ]Form 20-F [ ]Form 11-K [X]Form 10-Q [ ]Form N-SAR

                      For Period Ended: September 30, 2002

[ ] Transition Report on Form 10-K
[ ] Transition Report on Form 20-F
[ ] Transition Report on Form 11-K
[ ] Transition Report on Form 10-Q
[ ] Transition Report on Form N-SAR
For the Transition Period Ended: ___________________

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Read Instruction (on back page) Before Preparing Form, Please Print or Type
Nothing in this form shall be construed to imply that the Commission has
verified any information contained herein.

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If the notification relates to a portion of the filing checked above, identify
the Item(s) to which the notification relates: N/A
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PART I -- REGISTRANT INFORMATION

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Full Name of Registrant: Mirant Corporation
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Former Name if Applicable: Southern Energy Inc.

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Address of Principal Executive Office (Street and Number, City)
1155 Perimeter Center West, Atlanta, Georgia 30338-5414

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PART II -- RULES 12b-25(b) AND (c)

If the subject report could not be filed without unreasonable effort or expense
and the registrant seeks relief pursuant to Rule 12b-25(b), the following should
be completed. (Check box if appropriate)

      (a) The reasons described in reasonable detail in Part III of this form
      could not be eliminated without unreasonable effort or expense; (b) The
      subject annual report, semi-annual report, transition report on Form 10-K,
      Form 20-F,11-K or Form N-SAR, or portion thereof, will be filed
[     ] on or before the fifteenth calendar day following the prescribed due
      date; or the subject quarterly report of transition report on Form 10-Q,
      or portion thereof will be filed on or before the fifth calendar day
      following the prescribed due date; and (c) The accountant's statement or
      other exhibit required by Rule 12b-25(c) has been attached if applicable.

PART III - NARRATIVE

As a result of our focus on addressing the accounting issues discussed in our
Form 10-Q for the period ended June 30, 2002, which was filed with the SEC on
November 7, 2002, we are unable to timely complete the filing of our quarterly
report on Form 10-Q for the period ended September 30, 2002.


PART IV-- OTHER INFORMATION

(1) Name and telephone number of person to contact in regard to this
notification


Douglas L. Miller                  678                          579-5000
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      (Name)                   (Area Code)                (Telephone Number)

(2) Have all other periodic reports required under Section 13 or 15(d) of the
Securities Exchange Act of 1934 or Section 30 of the Investment Company Act of
1940 during the preceding 12 months or for such shorter period that the
registrant was required to file such report(s) been filed? If answer is no,
identify report(s). [X]Yes  [ ]No
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(3) Is it anticipated that any significant change in results of operations from
the corresponding period for the last fiscal year will be reflected by the
earnings statements to be included in the subject report or portion thereof? [
]Yes [X]No

If so, attach an explanation of the anticipated change, both narratively and
quantitatively, and, if appropriate, state the reasons why a reasonable estimate
of the results cannot be made.



                               Mirant Corporation
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                  (Name of Registrant as Specified in Charter)

has caused this notification to be signed on its behalf by the undersigned
hereunto duly authorized.


Date: November 15, 2002                       By /s/ Douglas L. Miller
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                                              Douglas L. Miller, General Counsel