UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 9)

EARTHSTONE ENERGY, INC.

(Name of Issuer)

Class A Common Stock, $0.001 par value per share

(Title of Class of Securities)

27032D304

(CUSIP Number)

D. Martin Phillips

EnCap Investments L.P.

9651 Katy Freeway Suite 600

Houston, TX 77024

(713) 659-6100

with a copy to:

W. Matthew Strock

Vinson & Elkins L.L.P.

845 Texas Avenue, Suite 4700

Houston, TX 77002 (713) 758-2222

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

April 14, 2022

(Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.  ☐

NOTE: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See Rule 13d-7 for other parties to whom copies are to be sent.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

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Explanatory Note

This Amendment No. 9 (this “Amendment”) amends and supplements the Schedule 13D filed on May 27, 2014 (the “First Schedule 13D”) by Oak Valley Resources, LLC, a Delaware limited liability company (“Oak Valley”), as amended by Amendment No. 1 filed by Oak Valley on November 16, 2016 (the “Second Schedule 13D”), as further amended by Amendment No. 2 filed by Bold Energy Holdings, LLC, a Texas limited liability company (“Bold”), on June 1, 2018 (the “Third Schedule 13D”), as further amended by Amendment No. 3 filed by Bold on October 25, 2018 (the “Fourth Schedule 13D”), as further amended by Amendment No. 4 filed by Bold on October 30, 2019 (the “Fifth Schedule 13D”), as further amended by Amendment No. 5 filed by Bold on December 23, 2020 (the “Sixth Schedule 13D”), as further amended by Amendment No. 6 filed by Bold on January 12, 2021 (the “Seventh Schedule 13D”), as further amended by Amendment No. 7 filed by Bold on October 27, 2021 (the “Eighth Schedule 13D”) and as further amended by Amendment No. 8 filed by Bold on February 7, 2022 (the “Ninth Schedule 13D” and, together with the First Schedule 13D, the Second Schedule 13D, the Third Schedule 13D, the Fourth Schedule 13D, the Fifth Schedule 13D, the Sixth Schedule 13D, the Seventh Schedule 13D and the Eight Schedule 13D, the “Original Schedule 13D” and, the Original Schedule 13D as further amended and supplemented by this Amendment, the “Schedule 13D”), and relates to the beneficial ownership of the shares of Class A common stock, $0.001 par value per share, of Earthstone Energy, Inc., a Delaware corporation (“Earthstone”). 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.

This Amendment amends and restates Item 2 of the Original Schedule 13D in its entirety as set forth below:

This Schedule 13D is being filed by Bold, EnCap Partners GP, LLC, a Delaware limited liability company (“EnCap Partners GP”), EnCap Energy Capital Fund VII, L.P. (“EnCap Fund VII”), EnCap Energy Capital Fund VIII, L.P. (“EnCap Fund VIII”), EnCap Energy Capital Fund IX, L.P. (“EnCap Fund IX”) and EnCap Energy Capital Fund XI, L.P. (“EnCap Fund XI”), each a Texas limited partnership (collectively, the “EnCap Funds”). Bold, the EnCap Funds and EnCap Partners GP (collectively, the “EnCap Entities”) are sometimes referred to in this Schedule 13D individually as a “Reporting Person” and, collectively, they are referred to herein as the “Reporting Persons.”

The principal business of Bold is its investment in the securities of Earthstone. 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 address of the principal office of the EnCap Entities is 9651 Katy Freeway, Suite 600, Houston, Texas 77024.

Information regarding the executive officers, managers or other control persons of Bold, the EnCap Funds and EnCap Partners GP is set forth on Schedule A, Schedule B and Schedule C, respectively, attached hereto. Schedule A, Schedule B and Schedule C attached hereto set forth the following information as to each such person:

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Other than as set forth on Schedule B attached hereto, during the last five years, to the best of the Reporting Person’s knowledge, no person named on Schedule A, Schedule B or Schedule C attached hereto, has been (a) convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors) or (b) a party to 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.

This Amendment amends and restates the sections entitled “Earthstone Securities Purchase Agreement” and “Post Oak Securities Purchase Agreement” contained in Item 4 of the Original Schedule 13D in their entirety as follows:

Earthstone Securities Purchase Agreement

On January 30, 2022, Earthstone entered into a securities purchase agreement (the “Earthstone SPA”) with EnCap Fund XI, an affiliate of EnCap Investments, and Cypress Investments, LLC, a fund managed by Post Oak Energy Capital, LP (“Post Oak”), to sell, in a private placement (the “Private Placement”), 280,000 shares of newly authorized Series A Convertible Preferred Stock, $0.001 par value per share (the “Preferred Stock”), each share of which will be convertible into 90.0900900900901 shares of Class A Common Stock for anticipated gross proceeds of $280.0 million, at a price of $1,000.00 per share of Preferred Stock (or $11.10 per share of Class A Common Stock on an as-converted basis). On April 14, 2022, immediately following the consummation of the transactions contemplated by that certain Purchase and Sale Agreement, dated as of January 30, 2022, by and among Bighorn Asset Company, LLC, EEH and Earthstone (the “Bighorn Acquisition”), the Private Placement was consummated in accordance with the terms of the Earthstone SPA, and, in connection therewith, Earthstone sold and issued 220,000 shares of Preferred Stock to EnCap Fund XI for an aggregate purchase price of $220.0 million.

The Earthstone SPA contains customary representations and warranties by Earthstone, Post Oak and EnCap Fund XI, and Earthstone has agreed to indemnify each investor for losses resulting from Earthstone’s breach of any representations, warranties or covenants. As of the date of the Earthstone SPA, EnCap Investments and its affiliates beneficially owned approximately 46.75% of the outstanding voting power of Earthstone. Two of Earthstone’s directors are employed by EnCap Investments. The Earthstone SPA and the Private Placement were evaluated and approved by the audit committee of the board of directors of Earthstone.

In connection with the closing of the Earthstone SPA, EnCap Fund XI, Post Oak and Earthstone entered into a Registration Rights Agreement, dated April 14, 2022 (the “Earthstone RRA”). Pursuant to the terms of the Earthstone RRA, Earthstone will, among other things, file a registration statement on Form S-3 with the Securities and Exchange Commission within 75 days after the closing of the Earthstone SPA providing for the registration of the shares of Class A Common Stock underlying the Preferred Stock and cooperate in certain underwritten offerings thereof.

In connection with the closing of the Earthstone SPA, Warburg, EnCap Investments, Post Oak and Earthstone entered into a Voting Agreement (the “Post Oak Voting Agreement”), dated as of April 14, 2022, containing provisions by which Post Oak has the right to nominate one director to the Board so long as Post Oak and its affiliates, in the aggregate, own 5.5% of the outstanding shares of Common Stock. Post Oak nominated Frost W. Cochran pursuant to the Post Oak Voting Agreement, and the Board appointed Mr. Cochran as Class II director to hold officer until Earthstone’s the 2023 annual meeting of its stockholders and the election of his successor.

In connection with the closing of the Earthstone SPA, on April 14, 2022, EEH amended and restated the First Amended and Restated Limited Liability Company Agreement of EEH pursuant to the Second Amended and Restated Limited Liability Company Agreement of EEH (the “Second LLC Agreement”) in order to provide for preferred units and update certain tax provisions therein.

The foregoing description of the Earthstone SPA, the Earthstone RRA, the Post Oak Voting Agreement and the Second LLC Agreement does not purport to be complete and is qualified in its entirety by the actual Earthstone SPA, Earthstone RRA, Post Oak Voting Agreement and Second LLC Agreement, copies of which are filed as Exhibit 10.10 to the Ninth Schedule 13D and Exhibits 10.12, 10.13 and 10.14 to this Amendment, respectively, and incorporated herein by reference.

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Post Oak Securities Purchase Agreement

On January 30, 2022, Post Oak and EnCap Fund VII entered into a Securities Purchase Agreement (the “Post Oak SPA”) providing for, among other things, the acquisition by Post Oak of 4,611,808 shares of Class A Common Stock of Earthstone from EnCap Fund VII at a purchase price of $11.10 per share of Class A Common Stock (the “Post Oak Acquisition”) and the making of customary representations and warranties by Post Oak and EnCap Fund VII in connection therewith. On April 14, 2022, the Post Oak Acquisition was consummated in accordance with the terms of the Post Oak SPA and, as a result thereof, EnCap Fund VII ceased to beneficially own any shares of Class A Common Stock.

The foregoing description of the Post Oak SPA does not purport to be complete and is qualified in its entirety by the actual Post Oak SPA, a copy of which is filed as Exhibit 10.11 to the Ninth Schedule 13D and incorporated herein by reference.

This Amendment amends Item 4 of the Original Schedule 13D to include the following after the final paragraph:

Certificate of Designation

On April 13, 2022, Earthstone filed with the Secretary of State of the State of Delaware a Certificate of Designation, Preferences, Rights and Limitations of Series A Convertible Preferred Stock (the “Certificate of Designations”), which created the Preferred Stock issued by Earthstone at the consummation of the transactions contemplated by the Earthstone SPA on April 14, 2022.

Each share of Preferred Stock will be convertible into a number of shares of Class A Common Stock determined by dividing the liquidation preference of the Preferred Stock, which is equal to the liquidation price plus the amount of any accrued and unpaid dividends through the date of conversion, by the conversion price. No dividend will be paid on the Preferred Stock if it converts into Class A Common Stock on or before October 1, 2022. Accordingly, until such date each share of Preferred Stock will automatically convert into 90.0900900900901 shares of Class A Common Stock at an initial conversion price of $11.10 per share of Class A Common Stock. The Preferred Stock will convert automatically on the 20th calendar day after Earthstone mails a definitive information statement to holders of its Common Stock notifying them that holders of a majority of the outstanding Common Stock have consented to the conversion feature of the Preferred Stock and the issuance of Class A Common Stock upon conversion of the Preferred Stock. As of January 30, 2022, Earthstone had received written consent for the conversion feature of the Preferred Stock and the issuance of the Class A Common Stock issuable upon conversion of the Preferred Stock from stockholders representing more than 50% of Earthstone’s outstanding Common Stock. The initial conversion price is subject to adjustment in certain circumstances, including stock splits, stock dividends, rights offerings, or combinations of Class A Common Stock.

If the Preferred Stock has not automatically converted into Class A Common Stock on or before October 1, 2022, then each holder of Preferred Stock will be entitled to receive dividends at an annual rate of 8% of the initial liquidation preference per share from the date of issuance. If a cash dividend is not declared and paid on any dividend payment date, then the liquidation preference per share of Preferred Stock will be increased by the amount of the unpaid dividend.

Earthstone will be required to redeem all of the outstanding shares of Preferred Stock if the Preferred Stock has not been converted into Class A Common Stock on or before November 22, 2025.

Except as expressly required by law, the holders of Preferred Stock have no voting rights, including the right to elect directors, and their consent is not required for taking corporate action.

The foregoing description of the Certificate of Designations does not purport to be complete and is qualified in its entirety by the actual Certificate of Designations, a copy of which is filed as Exhibit 10.15 to this Amendment and incorporated herein by reference.

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This Amendment amends and restates Item 5 of the Original Schedule 13D in its entirety as set forth below:

(a) The aggregate number and percentage of Class A 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 Schedule 13D relating to such Reporting Person and is incorporated by reference herein. The Reporting Persons, Post Oak and the Warburg Entities comprise a group within the meaning of Section 13(d)(3) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). See Item 2 above.

(b) For purposes of Rule 13d-3 promulgated under the Exchange Act, EnCap Partners GP has the shared power to vote or to direct the vote and to dispose or to direct the disposition of the Class A Common Stock held by the EnCap Funds. The shares held by the EnCap Funds represent approximately 41.89% of the outstanding shares of Class A Common Stock (an assumed combined total of 133,886,110 shares of Class A Common Stock outstanding, which (a) consists of 73,301,255 shares of Class A Common Stock outstanding as of March 3, 2022, as reported by Earthstone in its Annual Report, (b) consists of 6,808,511 shares of Class A Common Stock issued in connection with the Bighorn Acquisition and (c) assumes that (i) all 33,956,524 shares of Class B Common Stock beneficially owned by the Reporting Persons (along with an equivalent number of EEH Units, but no other shares of Class B Common Stock or EEH Units) were exchanged for newly-issued shares of Class A Common Stock on a one-for-one basis and (ii) all 220,000 shares of Preferred Stock beneficially owned by the Reporting Persons were automatically converted into 19,819,820 newly-issued shares of Class A Common Stock pursuant to the Earthstone SPA). Neither the filing of this Schedule 13D nor any of its contents shall be deemed to constitute an admission by any Reporting Person that it is the beneficial owner of any shares of Class A Common Stock for purposes of Section 13(d) of the Exchange Act, or for any other purpose, and such beneficial ownership is expressly disclaimed.

By virtue of the arrangements of the Reporting Persons with Warburg under the Warburg Voting Agreement, as amended, and with Warburg and Post Oak under the Post Oak Voting Agreement, including the mutual agreement to vote their voting stock for the election of the persons named in Earthstone’s proxy statement as its board of directors’ nominees for election as directors, and against any other nominees, the Reporting Persons may be deemed to be members of a “group” with Warburg and Post Oak. The Reporting Persons expressly disclaim any beneficial ownership of shares of Class A Common Stock held of record by Warburg and Post Oak and the numbers of shares reported in the cover pages as shared voting power do not include those shares of Class A Common Stock. As of the date of this Amendment, the Reporting Persons are the record holders of an aggregate of 2,303,000 shares of Class A Common Stock, 33,956,524 shares of Class B Common Stock and 220,000 shares of Preferred Stock and, to the knowledge of the Reporting Persons, Warburg is the record holder of 26,389,956 shares of Class A Common Stock and Post Oak is the record holder of 4,611,808 shares of Class A Common Stock and 60,000 shares of Preferred Stock. In the aggregate any group formed thereby would beneficially own 92,486,513 shares of Class A Common Stock in the aggregate, or approximately 66.40% of Earthstone’s outstanding shares of Class A Common Stock (calculated on the basis of an assumed combined total of 139,291,515 shares of Class A Common Stock outstanding, which (a) consists of 73,301,255 shares of Class A Common Stock outstanding as of March 3, 2022, as reported by Earthstone in its Annual Report, (b) consists of 6,808,511 shares of Class A Common Stock issued in connection with the Bighorn Acquisition and (c) assumes that (i) all 33,956,524 shares of Class B Common Stock beneficially owned by the Reporting Persons (along with an equivalent number of EEH Units, but no other shares of Class B Common Stock or EEH Units) were exchanged for newly-issued shares of Class A Common Stock on a one-for-one basis and (ii) all (A) 220,000 shares of Preferred Stock beneficially owned by the Reporting Persons and (B) 60,000 shares of Preferred Stock beneficially owned by Post Oak were automatically converted into 25,225,225 newly-issued shares of Class A Common Stock in the aggregate pursuant to the Earthstone SPA).

Each of Warburg and Post Oak has filed, or from time to time may file, separate statements of beneficial ownership on Schedule 13D pursuant to Rule 13d-1(k)(2) under the Act containing information required of Warburg or Post Oak, as applicable, with respect to the voting agreements described in this Item 5 or related matters. The Reporting Persons assume no responsibility for the information contained in any filings by any other person, including Warburg and Post Oak.

(c) Except as set forth in this Schedule 13D, none of the Reporting Persons or, to their knowledge, any of its directors, executive officers or other control persons named on Schedule A, Schedule B or Schedule C, attached hereto, has effected any transaction in the shares of Class A Common Stock during the past 60 days.

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(d) No person other than the Reporting Persons have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the shares of Class A Common Stock reported on this Schedule 13D.

(e) On April 14, 2022, EnCap Fund VII ceased to be the beneficial owner of more than five percent of the Class A Common Stock.

This Amendment amends and restates Item 7 of the Original Schedule 13D in its entirety as set forth below:

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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: April 20, 2022

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Schedule A

CONTROL PERSONS OF BOLD

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 Bold are set forth below:

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Schedule B

CONTROL PERSONS OF THE ENCAP FUNDS

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 the EnCap Funds are set forth below:

On July 10, 2018, EnCap Investments L.P. (“EnCap”) entered into a settlement with the Securities and Exchange Commission (“SEC”) under which EnCap consented to the entry of an order (the “Order”) that finds that EnCap 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 these proceedings, EnCap admitted to the SEC’s jurisdiction, the subject matter of these proceedings and consented to the Order. The Order required EnCap 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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Schedule C

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 each of the general partner and other control persons of EnCap Partners GP are set forth below. Except as indicated below, all members of the Board of Managers of EnCap Partners GP listed below are citizens of the United States.