SGY Stone Energy Corp.

SCHEDULE 13D

SCHEDULE 13D

This Schedule 13D (this “ Schedule 13D ”) is being filed by the undersigned, pursuant to §240.13d-1(a), with respect to the common stock, par value $0.01 per share (the “ Stone Common Stock ”), of Stone Energy Corporation, a Delaware corporation (the “ Issuer ” or “ Stone ”), the principal executive offices of which are located at 625 E. Kaliste Saloom Road, Lafayette, Louisiana, 70508.

This Schedule 13D is filed on behalf of Talos Energy LLC, a Delaware limited liability company (the “ Reporting Person ” or “ Talos ”). Talos is a manager-managed limited liability company with a board of directors.

The principal business of Talos is the exploration, development and acquisition of natural gas and oil properties.

The principal business address of Talos is 500 Dallas Street, Suite 2000, Houston, Texas 77002.

The name, present principal occupation or employment and citizenship of each director and executive officer, as applicable, of the Reporting Person is provided in Annex A to this Schedule 13D, which is incorporated by reference herein.

During the last five years, neither the Reporting Person nor, to the Reporting Person’s knowledge, any of the persons listed in Annex A has (i) been convicted in any criminal proceeding (excluding traffic violations or similar misdemeanors) or (ii) been a party to a civil proceeding of a judicial or administrative body of competent jurisdiction such that, as a result of such proceeding, such person was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activity subject to, federal or state securities laws or finding any violation with respect to such laws.

On November 21, 2017, Talos entered into a Transaction Agreement (the “ Transaction Agreement ”) with the Issuer, Talos Production LLC, a Delaware limited liability company and wholly owned subsidiary of Talos (“ Talos Production ” and together with Talos, the “ Talos Entities ”), Sailfish Energy Holdings Corporation, a Delaware corporation and wholly owned subsidiary of Issuer (“ New Sailfish ”) and Sailfish Merger Sub Corporation, a Delaware corporation and wholly owned subsidiary of New Sailfish (“ Merger Sub ”), that provides, among other things, for the combination of the Talos Entities with the Issuer.

On November 21, 2017, contemporaneously with the execution of the Transaction Agreement, each of Franklin Advisers, Inc. and MacKay Shields LLC (collectively, the “ Specified Stone Stockholders ”) entered into a Voting Agreement (the “ Voting Agreements ”) with Talos and Stone with respect to the Transaction Agreement.

The shares of Stone Common Stock to which this Schedule 13D relates have not been purchased by Talos, and no funds were expended in connection with the execution of either the Transaction Agreement or the Voting Agreements.

The Transaction Agreement provides that, upon the terms and subject to the conditions set forth therein, Merger Sub will be merged with and into the Issuer, with the Issuer continuing as the surviving entity and a wholly owned subsidiary of New Sailfish (the “ Merger ”) and as a result of the Merger, each issued and outstanding share of Stone Common Stock will be converted into the right to receive one share of common stock, par value $0.01 per share, of New Sailfish (the “ New Sailfish Common Stock ”). Immediately following the Merger, in a series of transactions, the Talos Entities will be combined with the Issuer and New Sailfish Common Stock will be issued to the members of Talos and certain other Talos shareholders (together with the Merger, the “ Transactions ”).

The completion of the Transactions is subject to satisfaction or waiver of closing conditions, including (1) the adoption of the Transaction Agreement by Stone stockholders, (2) the effectiveness of the registration statement on Form S-4 pursuant to which the shares of New Sailfish Common Stock issuable in the Transactions are registered with the Securities and Exchange Commission, (3) the authorization for listing of New Sailfish Common Stock

SCHEDULE 13D

issuable pursuant to the Transactions on the New York Stock Exchange, (4) there being no law or injunction prohibiting the consummation of the Transactions, (5) the substantially concurrent consummation of certain debt exchange transactions involving the Talos Entities and Stone, (6) subject to specified materiality standards, the accuracy of the representations and warranties of the other party, (7) compliance by the other party in all material respects with its covenants, and (8) other customary conditions such as expiration of the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended.

The Voting Agreements generally require that each of the Specified Stone Stockholders deliver written consents in respect of, or otherwise vote or cause to be voted, all Stone Common Stock owned by such Specified Stone Stockholder in favor of the Transaction Agreement and against alternative transactions, subject to certain exceptions. Further, in the event that the board of directors of Stone changes its recommendation to the Stone stockholders to vote in favor of the adoption of the Transaction Agreement, as permitted under the Transaction Agreement, the number of shares of Stone Common Stock the Specified Stone Stockholders will be obligated to vote in favor of the Transaction Agreement will be reduced on a pro rata basis such that the total shares of Stone Common Stock required to vote in favor of the Transaction Agreement under the Voting Agreements will not be more than 35% of the total outstanding Stone Common Stock.

The Voting Agreements also prohibit the Specified Stone Stockholders from soliciting alternative acquisition proposals, subject to certain exceptions. The Voting Agreements restrict the Specified Stone Stockholders from selling, transferring or otherwise disposing of Stone Common Stock owned by such Specified Stone Stockholders until the termination of the Voting Agreements, which shall occur upon the earliest to occur of (x) the effective time of the Merger, (y) the termination of the Transaction Agreement in compliance with its terms and (z) by mutual written consent of the parties to the Voting Agreements.

The transactions contemplated by the Transaction Agreement may, if consummated in accordance with its terms, result in any or all of the actions contemplated by subparagraphs (a)-(j) of Item 4 of Schedule 13D, including, without limitation, (i) the Merger, as a result of which the Issuer would become a wholly owned subsidiary of New Sailfish, (ii) the cessation of each existing Issuer director’s role as a director of Issuer, (iii) material changes in the capitalization, dividend policy and corporate structure of the Issuer, (iv) the restatement of the Issuer’s charter and bylaws, (v) the termination of the Issuer’s listing on NYSE and (vi) the termination of the Stone Common Stock’s registration under Section 12(g)(4) of the Exchange Act. Except for the transactions contemplated by the Transaction Agreement, neither the Reporting Person nor, to the Reporting Person’s knowledge, any of the persons listed in Annex A hereto, has any present plan or proposal that would relate to or result in any of the matters set forth in subparagraphs (a)-(j) of Item 4 of Schedule 13D.

The foregoing descriptions of the Transaction Agreement and the Voting Agreements set forth in this Item 4 do not purport to be complete and are qualified in their entirety by reference to the full text of the Transaction Agreement and the Voting Agreements, which are incorporated by reference as Exhibit A, Exhibit B and Exhibit C, respectively.

(a) and (b). The response of the Reporting Person to rows 7 through 13 on the cover page of this Schedule 13D are incorporated by reference herein.

As of the date hereof, the Reporting Person does not own any shares of Stone Common Stock. However, because of the Specified Stone Stockholders’ obligations under the Voting Agreements, Talos may be deemed to have shared voting power to vote up to an aggregate of 10,563,263 shares of Stone Common Stock in favor of the approval of the adoption of the Transaction Agreement and the approval of the Transactions and the other transactions contemplated by the Transaction Agreement. Thus, for purposes of Rule 13d-3 promulgated under the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”), Talos may be deemed to be the beneficial owner of an aggregate of 10,563,263 shares of Stone Common Stock.

The shares of Stone Common Stock subject to the Voting Agreements represent 52.8% of the outstanding shares of the outstanding Stone Common Stock, based on a total of 19,999,112 shares of Stone Common Stock outstanding as of November 21, 2017, as represented to the Reporting Person by the Issuer pursuant to the Transaction Agreement.

SCHEDULE 13D

The filing of this statement on Schedule 13D shall not be construed as an admission that the Reporting Person is, for the purposes of Section 13(d) or 13(g) of the Exchange Act, the beneficial owner of any of the shares of Stone Common Stock. Pursuant to Rule 13d-4, the Reporting Person disclaims all such beneficial ownership.

(c)    Except as set forth in this Schedule 13D with reference to the Transaction Agreement and the Voting Agreements, neither the Reporting Person nor, to the Reporting Person’s knowledge, any of the persons listed in Annex A hereto, has effected any transaction in the shares of Stone Common Stock during the past 60 days.

(d)    The Reporting Person has no right to receive dividends from, or the proceeds from the sale of, any shares of Stone Common Stock subject to the Voting Agreements. The Reporting Person will have no pecuniary interest in shares of Stone Common Stock unless and until the transactions contemplated by the Transaction Agreement are consummated.

(e)    Not applicable.

The description of the Transaction Agreement and the Voting Agreements in Item 4 are hereby incorporated into this Item 6 by reference. The copy of the Transaction Agreement included as Exhibit A and the copy of the Voting Agreements included as Exhibit B and Exhibit C are incorporated by reference herein.

Except as set forth herein, there are no contracts, understandings or relationships between the Reporting Person and any other person with respect to the Stone Common Stock.

SCHEDULE 13D

SIGNATURES

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Date: December 1, 2017

SCHEDULE 13D

Annex A

Directors and Executive Officers of Reporting Person

The name and citizenship of each director and executive officer of the Reporting Person are set forth below. The business address of each person listed below is c/o Talos Energy LLC, 500 Dallas Street, Suite 2000, Houston, Texas 77002. The present principal occupation or employment of each of the listed persons is set forth below.