Form: SCHEDULE 13D

General Statement of Acquisition of Beneficial Ownership






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. Checkbox not checked

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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SCHEDULE 13D




Comment for Type of Reporting Person:
Consists of (i) 19,350,897 shares of Class A common stock (as defined in Item 1(a)) held by FT-B (as defined in Item 2(a)), (ii) 83,355,210 shares of Class B common stock (the "Class B common stock") and 83,355,210 corresponding Class B Units of Enchanted Rock Holdings, LLC ("ER Holdings") held by Flagship (as defined in Item 2(a)) and (iii) 107,739 shares of Class A common stock underlying 111,545 Class M Units of ER Holdings, all of which are vested. The Class B Units are exchangeable, at the holder's option, on a one-for-one basis into shares of Class A common stock of the Issuer (as defined in Item 1(b)). Upon exchange of a Class B Unit, an equivalent number of shares of Class B common stock will be automatically cancelled. Vested Class M Units are convertible, at the holder's option, into a number of Class B Units generally equal to the product of (a) the number of vested Class M Units to be converted, and (b) a fraction, the numerator of which is the amount that would be distributed in respect of the vested Class M Unit (taking into account the applicable threshold amount), and the denominator of which is the amount that would be distributed in respect of a Class B Unit, in each case if, immediately before the exchange, ER Holdings were to sell all of its assets for their fair market values, pay any liabilities, and distribute the proceeds available for distribution, subject to certain adjustments. Class M Units have no expiration date. Each of EIF ER Holdings (as defined in Item 2(a)), as the sole owner of Flagship), FT-D (as defined in Item 2(a)), as owner of EIF ER Holdings) and EIP LLC (as defined in Item 2(a)), as the managing member of EIF ER Holdings and the general partner of FT-D) and Hans Kobler (as managing member of EIP LLC) may be deemed to have voting and dispositive power over the shares held by Flagship. Each of FT-B, EIP LLC (as the general partner of FT-B) and Mr. Kobler, a member of the Issuer's Board and the managing member of EIP LLC, may also be deemed to be the beneficial owners having shared voting power and shared investment power of the securities held by FT-B. Voting and investment decisions with respect to the securities described in this footnote are made by the investment committee of Energy Impact Partners LLC, which comprises seven individuals, including Mr. Kobler, Lindsay Luger ("Ms. Luger") and Sameer Reddy ("Mr. Reddy"), each of whom is a member of the Issuer's Board. Each member of this investment committee disclaims beneficial ownership of all securities described by this footnote except to the extent of his or her pecuniary interest therein. Based on 48,174,023 shares of Class A common stock outstanding as of June 11, 2026, following the closing of the Issuer's initial public offering of its Class A common stock (the "Offering"), as reported by the Issuer in its prospectus filed with the United States Securities and Exchange Commission (the "Commission") on June 10, 2026 (the "Prospectus"), assuming no exercise of the underwriters' option to purchase 4,186,046 additional shares of Class A common stock (the "Underwriters' Option").


SCHEDULE 13D




Comment for Type of Reporting Person:
Consists of 19,350,897 shares of Class A common stock held by FT-B. Each of EIP LLC (as the general partner of FT-B) and Mr. Kobler, a member of the Issuer's Board and the managing member of EIP LLC, may also be deemed to be the beneficial owners having shared voting power and shared investment power of the securities held by FT-B. Voting and investment decisions with respect to the securities described in this footnote are made by the investment committee of Energy Impact Partners LLC, which comprises seven individuals, including Mr. Kobler, Ms. Luger and Mr. Reddy, each of whom is a member of the Issuer's Board. Each member of this investment committee disclaims beneficial ownership of all securities described by this footnote except to the extent of his or her pecuniary interest therein. Based on 48,174,023 shares of Class A common stock outstanding as of June 11, 2026, following the closing of the Offering, as reported by the Issuer in the Prospectus, assuming no exercise of the Underwriters' Option.


SCHEDULE 13D




Comment for Type of Reporting Person:
Consists of (i) 83,355,210 shares of Class B common stock and 83,355,210 corresponding Class B Units held by Flagship and (ii) 107,739 shares of Class A common stock underlying 111,545 Class M Units, all of which are vested. The Class B Units are exchangeable, at the holder's option, on a one-for-one basis into shares of Class A common stock of the Issuer. Upon exchange of a Class B Unit, an equivalent number of shares of Class B common stock will be automatically cancelled. Vested Class M Units are convertible, at the holder's option, into a number of Class B Units generally equal to the product of (a) the number of vested Class M Units to be converted, and (b) a fraction, the numerator of which is the amount that would be distributed in respect of the vested Class M Unit (taking into account the applicable threshold amount), and the denominator of which is the amount that would be distributed in respect of a Class B Unit, in each case if, immediately before the exchange, ER Holdings were to sell all of its assets for their fair market values, pay any liabilities, and distribute the proceeds available for distribution, subject to certain adjustments. Class M Units have no expiration date. Each of EIF ER Holdings (as the sole owner of Flagship), FT-D (as owner of EIF ER Holdings) and EIP LLC (as the managing member of EIF ER Holdings and the general partner of FT-D) and Mr. Kobler, a member of the Issuer's Board and the managing member of EIP LLC, may be deemed to have voting and dispositive power over the shares held by Flagship. Voting and investment decisions with respect to the securities described in this footnote are made by the investment committee of Energy Impact Partners LLC, which comprises seven individuals, including Mr. Kobler, Ms. Luger and Mr. Reddy, each of whom is a member of the Issuer's Board. Each member of this investment committee disclaims beneficial ownership of all securities described by this footnote except to the extent of his or her pecuniary interest therein. Based on 48,174,023 shares of Class A common stock outstanding as of June 11, 2026, following the closing of the Offering, as reported by the Issuer in the Prospectus, assuming no exercise of the Underwriters' Option.


SCHEDULE 13D




Comment for Type of Reporting Person:
Consists of (i) 83,355,210 shares of Class B common stock and 83,355,210 corresponding Class B Units held by Flagship and (ii) 107,739 shares of Class A common stock underlying 111,545 Class M Units, all of which are vested. The Class B Units are exchangeable, at the holder's option, on a one-for-one basis into shares of Class A common stock of the Issuer. Upon exchange of a Class B Unit, an equivalent number of shares of Class B common stock will be automatically cancelled. Vested Class M Units are convertible, at the holder's option, into a number of Class B Units generally equal to the product of (a) the number of vested Class M Units to be converted, and (b) a fraction, the numerator of which is the amount that would be distributed in respect of the vested Class M Unit (taking into account the applicable threshold amount), and the denominator of which is the amount that would be distributed in respect of a Class B Unit, in each case if, immediately before the exchange, ER Holdings were to sell all of its assets for their fair market values, pay any liabilities, and distribute the proceeds available for distribution, subject to certain adjustments. Class M Units have no expiration date. Each of EIF ER Holdings (as the sole owner of Flagship), FT-D (as owner of EIF ER Holdings) and EIP LLC (as the managing member of EIF ER Holdings and the general partner of FT-D) and Mr Kobler, a member of the Issuer's Board and the managing member of EIP LLC, may be deemed to have voting and dispositive power over the shares held by Flagship. Voting and investment decisions with respect to the securities described in this footnote are made by the investment committee of Energy Impact Partners LLC, which comprises seven individuals, including Mr. Kobler, Ms. Luger and Mr. Reddy, each of whom is a member of the Issuer's Board. Each member of this investment committee disclaims beneficial ownership of all securities described by this footnote except to the extent of his or her pecuniary interest therein. Based on 48,174,023 shares of Class A common stock outstanding as of June 11, 2026, following the closing of the Offering, as reported by the Issuer in the Prospectus, assuming no exercise of the Underwriters' Option.


SCHEDULE 13D




Comment for Type of Reporting Person:
Consists of (i) 83,355,210 shares of Class B common stock and 83,355,210 corresponding Class B Units held by Flagship and (ii) 107,739 shares of Class A common stock underlying 111,545 Class M Units, all of which are vested. The Class B Units are exchangeable, at the holder's option, on a one-for-one basis into shares of Class A common stock of the Issuer. Upon exchange of a Class B Unit, an equivalent number of shares of Class B common stock will be automatically cancelled. Vested Class M Units are convertible, at the holder's option, into a number of Class B Units generally equal to the product of (a) the number of vested Class M Units to be converted, and (b) a fraction, the numerator of which is the amount that would be distributed in respect of the vested Class M Unit (taking into account the applicable threshold amount), and the denominator of which is the amount that would be distributed in respect of a Class B Unit, in each case if, immediately before the exchange, ER Holdings were to sell all of its assets for their fair market values, pay any liabilities, and distribute the proceeds available for distribution, subject to certain adjustments. Class M Units have no expiration date. Each of EIF ER Holdings (as the sole owner of Flagship), FT-D (as owner of EIF ER Holdings) and EIP LLC (as the managing member of EIF ER Holdings and the general partner of FT-D) and Mr. Kobler, a member of the Issuer's Board and the managing member of EIP LLC, may be deemed to have voting and dispositive power over the shares held by Flagship. Voting and investment decisions with respect to the securities described in this footnote are made by the investment committee of Energy Impact Partners LLC, which comprises seven individuals, including Mr. Kobler, Ms. Luger and Mr. Reddy, each of whom is a member of the Issuer's Board. Each member of this investment committee disclaims beneficial ownership of all securities described by this footnote except to the extent of his or her pecuniary interest therein. Based on 48,174,023 shares of Class A common stock outstanding as of June 11, 2026, following the closing of the Offering, as reported by the Issuer in the Prospectus, assuming no exercise of the Underwriters' Option.


SCHEDULE 13D




Comment for Type of Reporting Person:
Consists of (i) 19,350,897 shares of Class A common stock (as defined in Item 1(a)) held by FT-B (as defined in Item 2(a)), (ii) 83,355,210 shares of Class B common stock and 83,355,210 corresponding Class B Units held by Flagship (as defined in Item 2(a)) and (iii) 107,739 shares of Class A common stock underlying 111,545 Class M Units, all of which are vested. The Class B Units are exchangeable, at the holder's option, on a one-for-one basis into shares of Class A common stock of the Issuer (as defined in Item 1(b)). Upon exchange of a Class B Unit, the corresponding share of Class B common stock will be automatically cancelled. Vested Class M Units are convertible, at the holder's option, into a number of Class B Units generally equal to the product of (a) the number of vested Class M Units to be converted, and (b) a fraction, the numerator of which is the amount that would be distributed in respect of the vested Class M Unit (taking into account the applicable threshold amount), and the denominator of which is the amount that would be distributed in respect of a Class B Unit, in each case if, immediately before the exchange, ER Holdings were to sell all of its assets for their fair market values, pay any liabilities, and distribute the proceeds available for distribution, subject to certain adjustments. Class M Units have no expiration date. Each of EIF ER Holdings (as the sole owner of Flagship), FT-D (as owner of EIF ER Holdings), EIP LLC (as the managing member of EIF ER Holdings and the general partner of FT-D) and Mr. Kobler, a member of the Issuer's Board and the managing member of EIP LLC, may be deemed to have voting and dispositive power over the shares held by Flagship. Each of FT-B, EIP LLC (as the general partner of FT-B) and Mr. Kobler, a member of the Issuer's Board and the managing member of EIP LLC, may also be deemed to be the beneficial owners having shared voting power and shared investment power of the securities held by FT-B. Voting and investment decisions with respect to the securities described in this footnote are made by the investment committee of Energy Impact Partners LLC, which comprises seven individuals, including Mr. Kobler, Ms. Luger and Mr. Reddy, each of whom is a member of the Issuer's Board. Each member of this investment committee disclaims beneficial ownership of all securities described by this footnote except to the extent of his or her pecuniary interest therein. Based on 48,174,023 shares of Class A common stock outstanding as of June 11, 2026, following the closing of the Offering, as reported by the Issuer in the Prospectus, assuming no exercise of the Underwriters' Option.


SCHEDULE 13D


 
Energy Impact Partners LLC
 
Signature:/s/ Joshua J. Feldman
Name/Title:Joshua J. Feldman, Authorized Signatory
Date:06/18/2026
 
Energy Impact Fund (FT-B) LP
 
Signature:/s/ Joshua J. Feldman
Name/Title:Joshua J. Feldman, Authorized Signatory
Date:06/17/2026
 
EIP Flagship Fund I ER Holdings LLC
 
Signature:/s/ Joshua J. Feldman
Name/Title:Joshua J. Feldman, Authorized Signatory
Date:06/18/2026
 
EIF ER Holdings LLC
 
Signature:/s/ Joshua J. Feldman
Name/Title:Joshua J. Feldman, Authorized Signatory
Date:06/18/2026
 
Energy Impact Fund (FT-D) LP
 
Signature:/s/ Joshua J. Feldman
Name/Title:Joshua J. Feldman, Authorized Signatory
Date:06/18/2026
 
Hans Kobler
 
Signature:/s/ Joshua J. Feldman
Name/Title:Joshua J. Feldman, as attorney in fact for Hans Kobler
Date:06/18/2026