Primexx Energy Opportunity Fund, LP and Primexx Energy Opportunity Fund II, LP v. Primexx Energy Corporation, M. Christopher Doyle, Angelo Acconcia, Blackstone Inc., Blackstone Holdings III LP, Blackstone EMA II LLC, BMA VII LLC, Blackstone Energy Management Associates II LLC, Blackstone Energy Partners II LP, Blackstone Management Associates VII LLC, Blackstone Capital Partners VII LP, BCP VII/BEP II Holdings Manager LLC, BX Primexx Topco LLC, and BPP Holdco LLC

ACCEPTED 15-25-00120-CV FIFTEENTH COURT OF APPEALS AUSTIN, TEXAS 10/24/2025 3:16 PM No. 15-25-00120-CV CHRISTOPHER A. PRINE CLERK FILED IN IN THE COURT OF APPEALS 15th COURT OF APPEALS AUSTIN, TEXAS FOR THE FIFTEENTH DISTRICT OF TEXAS 10/24/2025 3:16:21 PM CHRISTOPHER A. PRINE Clerk PRIMEXX ENERGY OPPORTUNITY FUND L.P., ET AL., Appellants, V. PRIMEXX ENERGY CORPORATION, ET AL., Appellees.

Appeal From Texas Business Court, First Division Dallas County, Texas Honorable Bill Whitehill NOTICE OF APPEARANCE

TO THE HONORABLE FIFTEENTH COURT OF APPEALS: Please take notice that the following counsel from the law firm of Kirkland & Ellis, LLP, hereby enter their appearance as counsel of record for Appellee, Primexx Energy Corporation pursuant to Texas Rules of Appellate Procedure 6.1 and 6.2: Jeremy A. Fielding, P.C. – Lead Counsel State Bar No. 24040895 [email protected] Kasdin M. Mitchell, P.C.

State Bar No. 24135030 [email protected] KIRKLAND & ELLIS LLP 4550 Travis Street Dallas, Texas 75205 Telephone: (214) 972-1770 Facsimile: (214) 972-1771 Zack C. Ewing State Bar No. 24113650 [email protected] KIRKLAND & ELLIS LLP W. 4th Street Austin, Texas 78701 Telephone: (512)-678-9050 Facsimile: (512) 678-9101

Appellee respectfully requests that the Court, Clerk and all counsel of record take notice and direct all future correspondence and other papers filed in this matter to the counsel identified above.

Respectfully submitted, By: /s/ Jeremy A. Fielding, P.C.

Jeremy A. Fielding, P.C.

State Bar No. 24040895 [email protected] Kasdin M. Mitchell, P.C.

State Bar No. 24135030 [email protected] KIRKLAND & ELLIS LLP 4550 Travis Street Dallas, Texas 75205 Telephone: (214) 972-1770 Facsimile: (214) 972-1771

Zack C. Ewing State Bar No. 24113650 [email protected] KIRKLAND & ELLIS LLP W. 4th Street Austin, Texas 78701 Telephone: (512)-678-9050 Facsimile: (512) 678-9101 Attorneys For Appellee, Primexx Energy Corporation

CERTIFICATE OF SERVICE I certify that on October 24, 2025, a true and correct copy of the foregoing was served on all counsel of record through the electronic filing system in accordance with the Texas Rules of Appellate Procedure.

/s/ Jeremy A. Fielding, P.C.

Jeremy A. Fielding, P.C.

Automated Certificate of eService This automated certificate of service was created by the efiling system.

The filer served this document via email generated by the efiling system on the date and to the persons listed below. The rules governing certificates of service have not changed. Filers must still provide a certificate of service that complies with all applicable rules.

Gary Vogt on behalf of Jeremy Fielding Bar No. 24040895 [email protected] Envelope ID: 107273935 Filing Code Description: Other Document Filing Description: Notice of Appearance Status as of 10/24/2025 3:28 PM CST Case Contacts Name BarNumber Email TimestampSubmitted Status Roger Cowie 783886 [email protected] 10/24/2025 3:16:21 PM SENT Christopher Patton 24083634 [email protected] 10/24/2025 3:16:21 PM SENT NATALIE STALLBOHM [email protected] 10/24/2025 3:16:21 PM SENT SCOTT SMOOT [email protected] 10/24/2025 3:16:21 PM SENT Gary Vogt [email protected] 10/24/2025 3:16:21 PM SENT Griffin Vail [email protected] 10/24/2025 3:16:21 PM SENT Yaman Desai [email protected] 10/24/2025 3:16:21 PM SENT Austin Lesch [email protected] 10/24/2025 3:16:21 PM SENT Michael Patton [email protected] 10/24/2025 3:16:21 PM SENT Taylor Levesque [email protected] 10/24/2025 3:16:21 PM SENT Louisa Karam [email protected] 10/24/2025 3:16:21 PM SENT Kasdin Mitchell 24135030 [email protected] 10/24/2025 3:16:21 PM SENT Jeremy Fielding 24040895 [email protected] 10/24/2025 3:16:21 PM SENT Zack Ewing [email protected] 10/24/2025 3:16:21 PM SENT Nicholas Perrone [email protected] 10/24/2025 3:16:21 PM SENT Stephen Shackelford 24062998 [email protected] 10/24/2025 3:16:21 PM SENT

Associated Case Party: Primexx Energy Opportunity Fund, LP Name BarNumber Email TimestampSubmitted Status Sarah Hannigan [email protected] 10/24/2025 3:16:21 PM SENT Bryan Caforio [email protected] 10/24/2025 3:16:21 PM SENT Michelle Williams [email protected] 10/24/2025 3:16:21 PM SENT Automated Certificate of eService This automated certificate of service was created by the efiling system.

The filer served this document via email generated by the efiling system on the date and to the persons listed below. The rules governing certificates of service have not changed. Filers must still provide a certificate of service that complies with all applicable rules.

Gary Vogt on behalf of Jeremy Fielding Bar No. 24040895 [email protected] Envelope ID: 107273935 Filing Code Description: Other Document Filing Description: Notice of Appearance Status as of 10/24/2025 3:28 PM CST Associated Case Party: Primexx Energy Opportunity Fund, LP Michelle Williams [email protected] 10/24/2025 3:16:21 PM SENT Josephine Wang [email protected] 10/24/2025 3:16:21 PM SENT