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): November 3, 2014

ATHLON ENERGY INC.

(Exact Name of Registrant as Specified in its Charter)

Registrant’s telephone number, including area code: (817) 984-8200

Not Applicable

(Former Name or Former Address, if Changed Since Last Report)

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:

o                 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 1.01    Entry into a Material Definitive Agreement.

Amendment to Agreement and Plan of Merger

As previously announced, on September 27, 2014, Athlon Energy Inc., a Delaware corporation (the “Company”), Encana Corporation, a Canadian corporation (“Parent”), and Alenco Acquisition Company Inc., a Delaware corporation and indirect, wholly owned subsidiary of Parent (“Purchaser”), entered into a definitive Agreement and Plan of Merger (the “Merger Agreement”), pursuant to which Parent, through Purchaser, commenced an offer (the “Offer”) to acquire all of the outstanding shares of the Company’s common stock, par value $0.01 per share (the “Shares”), for $58.50 per share in cash, without interest.

On November 3, 2014, the Company entered into an amendment to the Merger Agreement with Parent and Purchaser (the “Amendment to Merger Agreement”) to:  (a) amend the definition of “Material Adverse Effect” such that no change, event, circumstance or development that occurs after 12:00 midnight, New York City time, on November 7, 2014 (one minute after 11:59 p.m., New York City time, on November 7, 2014) shall be deemed to be, or taken into account in determining whether there has been or would reasonably be expected to be, a Material Adverse Effect, (b) reduce the amount of the Company Termination Fee from $207.5 million to $59.3 million, (c) waive the Company’s obligations to provide prior written notice to Parent for the Notice Period and to negotiate in good faith with Parent with respect to a Superior Proposal or Change of Board Recommendation, (d) require the Company to publicly disclose, within 24 hours, the fact of any bona fide and written Acquisition Proposal having been made, provided such Acquisition Proposal would result in any person or entity becoming the beneficial owner (as such term is defined in Rule 13d-3 promulgated under the Securities Exchange Act of 1934, as amended) of 100% of the outstanding Shares or all or substantially all of the assets of the Company and its subsidiaries, taken as a whole, regardless of whether the Company’s Board of Directors affirmatively deems it a Superior Proposal, and (e) extend the initial expiration date of the Offer until 12:00 midnight, New York City time, on November 12, 2014 (one minute after 11:59 P.M., New York City time, on November 12, 2014).

The foregoing description of the Amendment to Merger Agreement does not purport to be complete and is qualified in its entirety by reference to the Amendment to Merger Agreement, which is attached hereto as Exhibit 2.1.  Capitalized terms used and not defined herein shall have the meanings assigned to such terms in the Merger Agreement, as amended.  Please read the Company’s Current Report on Form 8-K filed with the Securities and Exchange Commission (the “SEC”) on October 2, 2014 for a more detailed summary of the Merger Agreement.

Release of Tender Support Agreement

As previously announced, on September 27, 2014, in connection with the Offer, each of (A) Robert C. Reeves, Nelson K. Treadway, Bud W. Holmes, David B. McClelland, James R. Plemons, Jennifer L. Palko, John Souders, Melvyn E. Foster, Jr. and William B. D. Butler (the “Officers”), (B) J. Barton Kalsu, Ted A. Gardner and Mark A. Stevens (the “Independent Directors”), and (C) Apollo Athlon Holdings, L.P. and AP Overseas VII (Athlon FC) Holdings, L.P. (“Apollo” and, together with the Officers and the Independent Directors, the “Supporting Stockholders”), solely in his/her/its capacity as a stockholder of the Company, entered into a Tender Support Agreement with Parent and Purchaser (each, a “Tender Support Agreement”). Under the terms of each Tender Support Agreement, the Supporting Stockholders agreed, among other things, to tender all Shares held or thereafter acquired by them in the Offer, which on a combined basis represented approximately 35.8 percent of the Shares on a fully diluted basis.

On November 3, 2014, Parent and Purchaser executed letters addressed to each Supporting Stockholder to the Tender Support Agreements, wherein Parent and Purchaser agreed to waive and release such Supporting Stockholder from all of their respective covenants and obligations under the Tender Support Agreements.

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Item 9.01.                                        Financial Statements and Exhibits.

(d) Exhibits.

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

Date: November 7, 2014

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