MR Montage Resources Corporation

CUSIP No. 27890G 100

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CUSIP No. 27890G 100

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CUSIP No. 27890G 100

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CUSIP No. 27890G 100

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CUSIP No. 27890G 100

EnCap Energy Capital Fund VIII, L.P., a Texas limited partnership (“EnCap Fund VIII”), EnCap Energy Capital Fund VIII Co-Investors, L.P., a Texas limited partnership (“EnCap Fund VIII Co-Invest” and together with EnCap Fund VIII and EnCap Fund IX, the “EnCap Funds”), collectively directly hold the 11,530,331 remaining shares of Common Stock. EnCap Partners GP, LLC (“EnCap Partners GP”) is the sole general partner of EnCap Partners, LP (“EnCap Partners”), which is the managing member of EnCap Investments Holdings, LLC (“EnCap Holdings”), which is the sole member of EnCap Investments GP, L.L.C. (“EnCap Investments GP”), which is the sole general partner of EnCap Investments L.P. (“EnCap Investments LP”). EnCap Investments LP is the sole general partner of EnCap Equity Fund VIII GP, L.P. (“EnCap Fund VIII GP”) and EnCap Equity Fund IX GP, L.P. (“EnCap Fund IX GP”). EnCap Fund VIII GP is the sole general partner of each of EnCap Fund VIII and EnCap Fund VIII Co-Invest. EnCap Fund IX GP is the sole general partner of EnCap Fund IX. Therefore, EnCap Partners GP may be deemed to share the right to direct the disposition of the Common Stock held by the EnCap Funds. EnCap Partners GP disclaims beneficial ownership of the reported Common Stock except to the extent of its pecuniary interest therein, and this statement shall not be deemed an admission that it is the beneficial owner of the reported Common Stock for the purposes of Section 13(d) of the Exchange Act or any other purpose.

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Explanatory Note

This Amendment No. 9 (this “Amendment”) amends the information provided in the Schedule 13D (the “Original Schedule 13D”) filed with the SEC by Eclipse Resources Holdings, L.P. (“Eclipse Holdings”), EnCap Fund VIII, EnCap Fund VIII Co-Invest, EnCap Fund IX, David B. Miller, D. Martin Phillips, Gary R. Petersen and Robert L. Zorich on July 7, 2014, as amended by that certain Amendment No. 1 filed on January 13, 2015, that certain Amendment No. 2 filed on February 2, 2015, that certain Amendment No. 3 filed on July 15, 2016, that certain Amendment No. 4 filed on September 30, 2016 (“Amendment No. 4”), that certain Amendment No. 5 filed on January 18, 2018, that certain Amendment No. 6 filed on September 2, 2018, that certain Amendment No. 7 filed on February 6, 2019 (“Amendment No. 7”) and that certain Amendment No. 8 filed on March 1, 2019 (“Amendment No. 8”). This Amendment amends the Original Schedule 13D on behalf of the undersigned to furnish the information set forth herein and relates to the beneficial ownership of the shares of common stock, $0.01 par value per share, of Montage Resources Corporation (formerly known as Eclipse Resources Corporation), a Delaware corporation (the “Issuer”). Except as otherwise specified in this Amendment, all items left blank remain unchanged in all material respects and any items that are reported are deemed to amend and restate the corresponding items in the Original Schedule 13D in their entirety. Capitalized terms used herein but not defined herein have the respective meanings ascribed to them in the Original Schedule 13D.

This Amendment is being filed on behalf of the reporting persons identified on the cover pages of this Amendment. Capitalized terms used in this Amendment and not otherwise defined shall have the same meanings ascribed to them in the Original Schedule 13D.

Item 2 of the Original Schedule 13D is amended and restated in its entirety as follows:

This statement is jointly filed by EnCap Energy Capital Fund VIII, L.P., a Texas limited partnership (“EnCap Fund VIII”), EnCap Energy Capital Fund VIII Co-Investors, L.P., a Texas limited partnership (“EnCap Fund VIII Co-Invest”), EnCap Energy Capital Fund IX, L.P., a Texas limited partnership (“EnCap Fund IX” and collectively with EnCap Fund VIII and EnCap Fund VIII Co-Invest, the “EnCap Funds”), EnCap Partners GP, LLC, a Delaware limited liability company (“EnCap Partners GP”), and TPR Residual Assets, LLC, a Delaware limited liability company and a wholly owned subsidiary of EnCap Fund IX (“TPR Residual,” and collectively with the EnCap Funds and EnCap Partners GP, the “Reporting Persons”). As a result of the dissolution of Eclipse Resources Holdings, L.P. (“Eclipse Holdings”), Eclipse Holdings is no longer a joint filer and ceased to be a Reporting Person immediately after the filing of Amendment No. 4. As a result of the TPR Contribution (as defined in Item 3), Travis Peak Resources, LLC, a Delaware limited liability company, ceased to be a Reporting Person immediately after the filing of Amendment No. 7. The remaining Reporting Persons will continue to file as a group statements on Schedule 13D with respect to their beneficial ownership of securities of the Issuer to the extent required by applicable law. Further, on April 6, 2017, EnCap Partners, LLC converted into a limited partnership with the name EnCap Partners, LP (“EnCap Partners”). In connection with the conversion, EnCap Partners GP was formed as the sole general partner of EnCap Partners. EnCap Partners GP replaced EnCap Partners, LLC as a Reporting Person and a joint filer.

The principal office and business address of each of the EnCap Funds, EnCap Partners GP and TPR Residual is 1100 Louisiana Street, Suite 4900, Houston, Texas 77002. The principal business of each of the EnCap Funds is investing in securities of energy companies and related assets. The principal business of EnCap Partners GP is indirectly managing the EnCap Funds. The principal business of TPR Residual is investing in the securities of energy companies and oil and gas interests ancillary thereto.

EnCap Partners GP is the sole general partner of EnCap Partners, which is the managing member of EnCap Investments Holdings, LLC (“EnCap Holdings”), which is the sole member of EnCap Investments GP, L.L.C. (“EnCap Investments GP”), which is the sole general partner of EnCap Investments L.P. (“EnCap Investments LP”). EnCap Investments LP is the sole general partner of EnCap Equity Fund VIII GP, L.P. (“EnCap Fund VIII GP”) and EnCap Equity Fund IX GP, L.P. (“EnCap Fund IX GP”). EnCap Fund VIII GP is the sole general partner of each of EnCap Fund VIII and EnCap Fund VIII Co-Invest. EnCap Fund IX GP is the sole general partner of EnCap Fund IX.

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None of the Reporting Persons or the Control Persons (as defined below) has, during the last five years, been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors). Other than as set forth on Schedule 5 attached hereto, to the best of the Reporting Persons’ knowledge, no Reporting Person or Control Person has, during the last five years, been a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws. Information regarding the executive officers, managers or other persons controlling EnCap Fund VIII, EnCap Fund VIII Co-Invest, EnCap Fund IX, EnCap Partners GP and TPR Residual is set forth on Schedule 1, Schedule 2, Schedule 3 and Schedule 5 (collectively, the “Control Persons”), which are attached hereto and hereby incorporated by reference. All such persons are citizens of the United States.

Item 3 of the Original Schedule 13D is amended to include the following after the final paragraph:

The description of the transactions as set forth in Item 4 below is incorporated by reference herein in its entirety.

Item 4 of the Original Schedule 13D is amended to include the following after the final paragraph:

The Reporting Persons acquired the Common Stock reported herein for investment purposes and the Reporting Persons intend to review on a continuing basis the investments in the Issuer by the Reporting Persons. Depending upon market conditions and other factors that they may deem relevant, the Reporting Persons or their affiliates may seek to acquire additional securities of the Issuer or other financial instruments related to the Issuer or its securities (which may include debt securities or other rights or securities exercisable or convertible into securities of the Issuer) and/or sell or otherwise dispose of some or all of the Issuer securities or financial instruments owned from time to time, in each case, in open market or private transactions, block sales or otherwise, including in connection with extraordinary corporate transactions such as a tender offer, merger or consolidation.

The Reporting Persons intend to communicate with the Issuer’s management and Company Board about a broad range of operational and strategic matters and may communicate with other shareholders or third parties regarding the foregoing. The Reporting Persons may in the future formulate, consider, explore, develop or make plans or proposals regarding the Issuer or its securities, including related to operational or financial matters or any other potential strategic alternative intended to maximize shareholder value, including but not limited to a take private transaction. Such discussions and actions may be preliminary and exploratory in nature and not rise to the level of a plan or a proposal.

Except as set forth herein, the Reporting Persons have no present plans or proposals that would relate to or result in any of the matters set forth in clauses (a) through (j) of Item 4 of Schedule 13D. Although the foregoing reflects activities presently contemplated by such persons with respect to the Issuer, the foregoing is subject to change at any time.

Subparagraphs (a), (b), (c) and (e) of Item 5 of the Original Schedule 13D are amended and restated in their entirety as follows:

(a) The aggregate number and percentage of Common Stock beneficially owned by each Reporting Person is set forth in Items 7, 8, 9, 10, 11 and 13 of the cover pages to this Amendment relating to such Reporting Person and is incorporated by reference herein.

(b) EnCap Partners GP is the sole general partner of EnCap Partners, which is the managing member of EnCap Holdings, which is the sole member of EnCap Investments GP, which is the sole general partner of EnCap Investments LP. EnCap Investments LP is the sole general partner of EnCap Fund VIII GP and EnCap Fund IX GP. EnCap Fund VIII GP is the sole general partner of each of EnCap Fund VIII and EnCap Fund VIII Co-Invest. EnCap Fund IX GP is the sole general partner of EnCap Fund IX. EnCap Partners GP has the shared power to vote or to direct the vote and to dispose or to direct the disposition of Common Stock held by the EnCap Funds.

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TPR Residual is member-managed by EnCap Fund IX. As a result, EnCap Fund IX may be deemed to have the shared power to vote or direct the vote or to dispose or direct the disposition of the shares owned by TPR Residual.

(c) No Reporting Person has effected any transactions in the shares of Common Stock during the past sixty (60) days.

(e) Not applicable.

Item 7 of the Original Schedule 13D is amended and restated in its entirety as follows:

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SIGNATURE

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: October 30, 2019

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Schedule 1

CONTROL PERSONS OF

ENCAP FUND VIII AND ENCAP FUND VIII CO-INVEST

The name, business address, present principal occupation or employment and the name, principal business and address of any corporation or other organization in which such employment is conducted, of each of the general partner and other control persons of EnCap Fund VIII and EnCap Fund VIII Co-Invest are set forth below:

EnCap Fund VIII and EnCap Fund VIII Co-Invest:

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Schedule 2

CONTROL PERSONS OF

ENCAP FUND IX

The name, business address, present principal occupation or employment and the name, principal business and address of any corporation or other organization in which such employment is conducted, of each of the general partner and other control persons of EnCap Fund IX are set forth below:

EnCap Fund IX:

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Schedule 3

CONTROL PERSONS OF

ENCAP PARTNERS GP

The name, business address, present principal occupation or employment and the name, principal business and address of any corporation or other organization in which such employment is conducted, of the general partner and each of the other control persons of EnCap Partners GP are set forth below:

EnCap Partners GP:

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Schedule 5

CONTROL PERSONS OF

TPR RESIDUAL

The name, business address, present principal occupation or employment and the name, principal business and address of any corporation or other organization in which such employment is conducted, of the sole member and each of the other control persons of TPR Residual are set forth below:

TPR Residual:

On July 10, 2018, EnCap Investments L.P. entered into a settlement with the U.S. Securities and Exchange Commission (“SEC”) under which EnCap Investments L.P. consented to the entry of an order (the “Order”) that found that EnCap Investments L.P. violated Section 206(4) under the Investment Advisers Act of 1940 (the “Advisers Act”) and Rule 206(4)-5 thereunder. Solely for the purpose of settling the proceedings, EnCap Investments L.P. admitted to the SEC’s jurisdiction, the subject matter of these proceedings and consented to the Order. The Order required EnCap Investments L.P. to cease and desist from committing or causing any violations and any future violations of Section 206(4) of the Advisers Act and Rule 206(4)-5 thereunder, to be censured, and to pay a civil monetary penalty in the amount of $500,000 to the SEC.

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