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): April 13, 2012

DUKE ENERGY CORPORATION

(Exact Name of Registrant as Specified in its Charter)

550 South Tryon Street, Charlotte, North Carolina  28202

(Address of Principal Executive Offices, including Zip code)

(704) 382-3853

(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 April 10, 2012, Duke Energy Corporation (the “Company”) and Progress Energy, Inc. (together with the Company, the “Companies”) received a request for additional information (“RAI”) from the Federal Energy Regulatory Commission (the “FERC”) in connection with their second wholesale market power mitigation plan filed on March 26, 2012 with the FERC as part of the Companies’ proposed merger.   On April 13, 2012, the Companies responded to the FERC’s RAI.  The Companies continue to target the closing of the merger on July 1, 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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