Supplemental Indenture No. 1, dated as of September 12, 2018, by and among Talos Production LLC, Talos Production Finance, Inc., Talos Energy Inc. and Wilmington Trust, National Association, as trustee and collateral agent

Exhibit 4.2

SUPPLEMENTAL INDENTURE NO. 1

SUPPLEMENTAL INDENTURE NO. 1 (this “Supplemental Indenture”) dated as of September 12, 2018, among TALOS ENERGY INC. (the “Parent Guarantor”), the parent company of TALOS PRODUCTION LLC, a Delaware limited liability company (“Holdings”), and Wilmington Trust, National Association, as trustee (the “Trustee”) and collateral agent (the “Collateral Agent”) under the indenture referred to below.

W I T N E S S E T H :

WHEREAS, Holdings, Talos Production Finance Inc. (or its successor), a Delaware corporation (the “Co-Issuer” and, together with Holdings, the “Issuers”), certain Subsidiary Guarantors and the Trustee have heretofore executed an indenture, dated as of May 10, 2018 (as amended, supplemented or otherwise modified, the “Indenture”), providing for the issuance of the Issuers’ 11.00% Second-Priority Senior Secured Notes due 2022 ( the “Notes”), initially in the aggregate principal amount of $390,867,820;

WHEREAS, Section 9.01(xii) of the Indenture permits the Issuers, the Trustee and the Collateral Agent to enter into a supplemental indenture, without the consent of any holder of Notes, to make any change that does not adversely affect the rights of any holder of Notes;

WHEREAS, the Parent Guarantor is the parent company of Holdings and the Issuers desire to add the Parent Guarantor as a guarantor of the Notes;

WHEREAS, the Issuers have requested that the Trustee and Collateral Agent execute and deliver this Supplemental Indenture. The Issuers have delivered to the Trustee and Collateral Agent the resolution of the Board of Directors authorizing the execution of this Supplemental Indenture, an Opinion of Counsel and an Officers’ Certificate pursuant to Sections 9.05, 13.04 and 13.05 of the Indenture; and

WHEREAS pursuant to Section 9.01 of the Indenture, the Trustee, the Collateral Agent and the Issuers are authorized to execute and deliver this Supplemental Indenture;

NOW THEREFORE, in consideration of the foregoing and for other good and valuable consideration, the receipt of which is hereby acknowledged, the Parent Guarantor, the Issuers, the Trustee and the Collateral Agent mutually covenant and agree for the equal and ratable benefit of the holders of the Notes as follows:

1.    Defined Terms. As used in this Supplemental Indenture, terms defined in the Indenture or in the preamble or recital hereto are used herein as therein defined, except that the term “holders” in this Supplemental Indenture shall refer to the term “holders” as defined in the Indenture and the Trustee acting on behalf of and for the benefit of such holders. The words “herein,” “hereof” and “hereby” and other words of similar import used in this Supplemental Indenture refer to this Supplemental Indenture as a whole and not to any particular Section hereof.

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2.    Amendments to Section 1.01. Section 1.01 of the Indenture is hereby amended by inserting the following definitions in alphabetical order:

“Guarantee” means any Subsidiary Guarantee and any guarantee of the obligations of the Issuers under this Indenture and the Notes by the Parent Guarantor in accordance with the provisions of this Indenture.

“Guarantor” means any Subsidiary Guarantor and the Parent Guarantor.

“Parent Guarantor” means Talos Energy Inc., a Delaware corporation and the parent company of Holdings.”

3.    Amendments to Article XII. Article XII of the Indenture is hereby deleted and amended and restated to read in its entirety as set forth below:

“ARTICLE XII

GUARANTEE

SECTION 12.01    Guarantee.

(a)    Each Guarantor hereby jointly and severally, irrevocably and unconditionally guarantees, on a senior basis, as a primary obligor and not merely as a surety, to each holder, to the Trustee and to the Collateral Agent and its successors and assigns (i) the performance and punctual payment when due, whether at Stated Maturity, by acceleration or otherwise, of all obligations of the Issuers under this Indenture and the Notes, whether for payment of principal of, premium, if any, or interest (or Additional Interest, if any) on the Notes and all other monetary obligations of the Issuers under this Indenture and the Notes and (ii) the full and punctual performance within applicable grace periods of all other obligations of the Issuers whether for fees, expenses, indemnification or otherwise under this Indenture and the Notes (all the foregoing being hereinafter collectively called the “Guaranteed Obligations”). The Guaranteed Obligations of all Guarantors shall be secured by security interests (subject to Permitted Liens and Liens permitted by Section 4.12) in the Collateral owned by such Guarantor pursuant to the terms of the Security Documents (but subject to the terms and conditions of the Security Documents and the Senior Lien Intercreditor Agreement). Each Guarantor further agrees that the Guaranteed Obligations may be extended or renewed, in whole or in part, without notice or further assent from any Guarantor, and that each Guarantor shall remain bound under this Article XII notwithstanding any extension or renewal of any Guaranteed Obligation.

(b)    Each Guarantor waives presentation to, demand of payment from and protest to the Issuers of any of the Guaranteed Obligations and also waives notice of protest for nonpayment. Each Guarantor waives notice of any default under the Notes or the Guaranteed Obligations. The obligations of each Guarantor hereunder shall not be affected by (i) the failure of any holder, the Collateral Agent or the Trustee to assert any claim or demand or to enforce any right or remedy against the Issuers or any other Person under this Indenture, the Notes or any other agreement or otherwise; (ii) any extension or renewal of this Indenture, the Notes or any other agreement; (iii) any rescission, waiver, amendment or modification of any of the terms or provisions of this Indenture, the Notes or any other agreement; (iv) the release of any security held by any holder, the Collateral Agent or the Trustee for the Guaranteed Obligations or each Guarantor; (v) the failure of any holder, the Collateral Agent or the Trustee to exercise any right or remedy against any other guarantor of the Guaranteed Obligations; or (vi) any change in the ownership of each Guarantor, except as provided in Section 12.02(b). Each Guarantor hereby waives any right to which it may be entitled to have its obligations hereunder divided among the Guarantors, such that such Guarantor’s obligations would be less than the full amount claimed.

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(c)    Each Guarantor hereby waives any right to which it may be entitled to have the assets of the Issuers first be used and depleted as payment of the Issuers’ or such Guarantor’s obligations hereunder prior to any amounts being claimed from or paid by such Guarantor hereunder. Each Guarantor hereby waives any right to which it may be entitled to require that the Issuers be sued prior to an action being initiated against such Guarantor.

(d)    Each Guarantor further agrees that its Guarantee herein constitutes a guarantee of payment, performance and compliance when due (and not a guarantee of collection) and waives any right to require that any resort be had by any holder or the Trustee to any security held for payment of the Guaranteed Obligations.

(e)    The Guarantee of each Guarantor is, to the extent and in the manner set forth in Article XII, equal in right of payment to all existing and future Pari Passu Indebtedness (but subject to the terms and conditions of the Security Documents and the Senior Lien Intercreditor Agreement), senior in right of payment to all existing and future Subordinated Indebtedness of such Guarantor.

(f)    Except as expressly set forth in Sections 8.01(b), 12.02 and 12.06, the obligations of each Guarantor hereunder shall not be subject to any reduction, limitation, impairment or termination for any reason, including any claim of waiver, release, surrender, alteration or compromise, and shall not be subject to any defense of setoff, counterclaim, recoupment or termination whatsoever or by reason of the invalidity, illegality or unenforceability of the Guaranteed Obligations or otherwise. Without limiting the generality of the foregoing, the obligations of each Guarantor herein shall not be discharged or impaired or otherwise affected by the failure of any holder, the Collateral Agent or the Trustee to assert any claim or demand or to enforce any remedy under this Indenture, the Notes or any other agreement, by any waiver or modification of any thereof, by any default, failure or delay, willful or otherwise, in the performance of the obligations, or by any other act or thing or omission or delay to do any other act or thing which may or might in any manner or to any extent vary the risk of any Guarantor or would otherwise operate as a discharge of any Guarantor as a matter of law or equity.

(g)    Each Guarantor agrees that its Guarantee shall remain in full force and effect until payment in full of all the Guaranteed Obligations. Each Guarantor further agrees that its Guarantee herein shall continue to be effective or be reinstated, as the case may be, if at any time payment, or any part thereof, of principal of or interest on any Guaranteed Obligation is rescinded or must otherwise be restored by any holder or the Trustee upon the bankruptcy or reorganization of the Issuers or otherwise.

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(h)    In furtherance of the foregoing and not in limitation of any other right which any holder, the Collateral Agent or the Trustee has at law or in equity against any Guarantor by virtue hereof, upon the failure of the Issuers to pay the principal of or interest on any Guaranteed Obligation when and as the same shall become due, whether at maturity, by acceleration, by redemption or otherwise, or to perform or comply with any other Guaranteed Obligation, each Guarantor hereby promises to and shall, upon receipt of written demand by the Trustee or Collateral Agent, forthwith pay, or cause to be paid, in cash, to the holders or the Trustee an amount equal to the sum of (i) the unpaid principal amount of such Guaranteed Obligations, (ii) accrued and unpaid interest on such Guaranteed Obligations (but only to the extent not prohibited by applicable law) and (iii) all other monetary obligations of the Issuers to the holders, the Collateral Agent and the Trustee.

(i)    Each Guarantor agrees that it shall not be entitled to any right of subrogation in relation to the holders in respect of any Guaranteed Obligations guaranteed hereby until payment in full of all Guaranteed Obligations. Each Guarantor further agrees that, as between it, on the one hand, and the holders, the Collateral Agent and the Trustee, on the other hand, (i) the maturity of the Guaranteed Obligations guaranteed hereby may be accelerated as provided in Article VI for the purposes of the Guarantee herein, notwithstanding any stay, injunction or other prohibition preventing such acceleration in respect of the Guaranteed Obligations guaranteed hereby, and (ii) in the event of any declaration of acceleration of such Guaranteed Obligations as provided in Article VI, such Guaranteed Obligations (whether or not due and payable) shall forthwith become due and payable by the Guarantors for the purposes of this Section 12.01.

(j)    Each Guarantor also agrees to pay any and all costs and expenses (including reasonable out-of-pocket attorneys’ fees and expenses) Incurred by the Trustee, the Collateral Agent or any holder in enforcing any rights under this Section 12.01.

(k)    Upon request of the Trustee, each Guarantor shall execute and deliver such further instruments and do such further acts as may be reasonably necessary or proper to carry out more effectively the purpose of this Indenture.

SECTION 12.02    Limitation on Liability.

(a) Any term or provision of this Indenture to the contrary notwithstanding, the maximum aggregate amount of the Guaranteed Obligations guaranteed hereunder by each Subsidiary Guarantor shall not exceed the maximum amount that can be hereby guaranteed by the applicable Subsidiary Guarantor without rendering the Subsidiary Guarantee or this Indenture, as it relates to such Subsidiary Guarantor, voidable under applicable law relating to fraudulent conveyance or fraudulent transfer or similar laws affecting the rights of creditors generally or capital maintenance or corporate benefit rules applicable to guarantees for obligations of affiliates.

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(b)    A Subsidiary Guarantee as to any Restricted Subsidiary that is (or becomes) a party hereto on the date hereof or that executes a supplemental indenture in accordance with Section 4.11 hereof and provides a guarantee shall terminate and be of no further force or effect and such Subsidiary Guarantee shall be deemed to be automatically released from all obligations under this Article XII upon any of the following:

(i)    the sale, disposition, exchange or other transfer (including through merger, consolidation, amalgamation or otherwise) of the Capital Stock (including any sale, disposition or other transfer following which the applicable Subsidiary Guarantor is no longer a Restricted Subsidiary), of the applicable Subsidiary Guarantor if such sale, disposition, exchange or other transfer is made to a person that is not an Issuer or a Restricted Subsidiary of Holdings in a transaction that is permitted by this Indenture;

(ii)    the designation of such Subsidiary Guarantor as an Unrestricted Subsidiary in accordance with the provisions of Section 4.04 and the definition of “Unrestricted Subsidiary”;

(iii)    [reserved];

(iv)    the Issuers’ exercise of their legal defeasance option or covenant defeasance option under Article VIII or if the Issuers’ obligations under this Indenture are discharged in accordance with the terms of this Indenture;

(v)    such Subsidiary ceasing to be a Subsidiary as a result of any foreclosure of any pledge or security interest in favor of First-Priority Lien Obligations or other exercise of remedies in respect thereof, subject to, in each case, the application of the proceeds of such foreclosure or exercise of remedies in the manner described in the Senior Lien Intercreditor Agreement; and

(vi)    as provided in Article IX.

SECTION 12.03    [Reserved].

SECTION 12.04    Successors and Assigns. This Article XII shall be binding upon each Guarantor and its successors and assigns and shall inure to the benefit of the successors and assigns of the Trustee and the holders and, in the event of any transfer or assignment of rights by any holder or the Trustee, the rights and privileges conferred upon that party in this Indenture and in the Notes shall automatically extend to and be vested in such transferee or assignee, all subject to the terms and conditions of this Indenture.

SECTION 12.05    No Waiver. Neither a failure nor a delay on the part of either the Trustee or the holders in exercising any right, power or privilege under this Article XII shall operate as a waiver thereof, nor shall a single or partial exercise thereof preclude any other or further exercise of any right, power or privilege. The rights, remedies and benefits of the Trustee and the holders herein expressly specified are cumulative and not exclusive of any other rights, remedies or benefits which either may have under this Article XII at law, in equity, by statute or otherwise.

SECTION 12.06    Modification. No modification, amendment or waiver of any provision of this Article XII, nor the consent to any departure by any Guarantor therefrom, shall in any event be effective unless the same shall be in writing and signed by the Trustee, and then such waiver or consent shall be effective only in the specific instance and for the purpose for which given. No notice to or demand on any Guarantor in any case shall entitle any Guarantor to any other or further notice or demand in the same, similar or other circumstances.

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SECTION 12.07    Execution of Supplemental Indenture for Future Subsidiary Guarantors. Each Subsidiary which is required to become a Subsidiary Guarantor of the Notes pursuant to Section 4.11 shall promptly execute and deliver to the Trustee a supplemental indenture in the form of Exhibit C hereto pursuant to which such Subsidiary shall become a Subsidiary Guarantor under this Article XII and shall guarantee the Notes. Concurrently with the execution and delivery of such supplemental indenture, Holdings shall deliver to the Trustee an Opinion of Counsel and an Officers’ Certificate certifying that such supplemental indenture has been duly authorized, executed and delivered by such Subsidiary and that, subject to the application of bankruptcy, insolvency, moratorium, fraudulent conveyance or transfer and other similar laws relating to creditors’ rights generally and to the principles of equity, whether considered in a proceeding at law or in equity, the Subsidiary Guarantee of such Subsidiary Guarantor is a valid and binding obligation of such Subsidiary Guarantor, enforceable against such Subsidiary Guarantor in accordance with its terms and/or to such other matters as the Trustee may reasonably request.

SECTION 12.08    Non-Impairment. The failure to endorse a Guarantee on any Note shall not affect or impair the validity thereof.

4.    Agreement to Guarantee. The Parent Guarantor hereby agrees, jointly and severally with all existing Subsidiary Guarantors, to unconditionally guarantee the Issuers’ Obligations under the Notes and the Indenture on the terms and subject to the conditions set forth in Article XII of the Indenture and to be bound by all other applicable provisions of the Indenture and the Notes and to perform all of the obligations and agreements of a Guarantor under the Indenture.

5.    Notices. All notices or other communications to the Parent Guarantor shall be given as provided in Section 13.02 of the Indenture.

6.    Ratification of Indenture; Supplemental Indentures Part of Indenture. Except as expressly amended hereby, the Indenture is in all respects ratified and confirmed and all the terms, conditions and provisions thereof shall remain in full force and effect. This Supplemental Indenture shall form a part of the Indenture for all purposes, and every holder of Notes heretofore or hereafter authenticated and delivered shall be bound hereby.

7.    Governing Law. THIS SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO PRINCIPLES OF CONFLICTS OF LAW.

8.    Trustee and Collateral Agent Make No Representation. Neither the Trustee nor the Collateral Agent makes any representation as to the validity or sufficiency of this Supplemental Indenture.

9.    Counterparts. The parties may sign any number of copies of this Supplemental Indenture. Each signed copy shall be an original, but all of them together represent the same agreement.

10.    Effect of Headings. The Section headings herein are for convenience only and shall not affect the construction thereof.

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IN WITNESS WHEREOF, the parties have caused this Indenture to be duly executed as of the date first written above.

[Signature Page to Supplemental Indenture]