UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): January 8, 2012

DUKE ENERGY CORPORATION

(Exact Name of Registrant as Specified in its Charter)

526 South Church Street, Charlotte, North Carolina  28202

(Address of Principal Executive Offices, including Zip code)

(704) 594-6200

(Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

x          Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o            Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o            Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o            Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240. 13e-4(c))

ITEM 8.01.                                    OTHER EVENTS

On January 8, 2012, Duke Energy Corporation (“Duke Energy”) and Progress Energy, Inc. (“Progress Energy”) mutually agreed to extend the Initial Termination Date, as defined in the Agreement and Plan of Merger dated as of January 8, 2011 by and among Duke Energy, Progress Energy and Diamond Acquisition Corporation, from January 8, 2012 to July 8, 2012.

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SIGNATURE

Pursuant to the requirements of the Securities and Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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