Hammons P. Hepner

Biography

Hammons is a trial and appellate attorney with experience in multiple trials and briefing issues and appeals at many state and federal courts. His practices area include class actions and complex litigation focused on agriculture, antitrust, consumer protection, and oil-and-gas law. In addition to his practice, Hammons spearheads the firm’s summer associate recruitment program.

Hammons graduated from the University of Oklahoma College Law in May 2021. During law school, his article examining the definition of “waters of the United States” under the Clean Water Act and its impact on agriculture was published in January 2021 in the Oklahoma Law Review. Before attending law school, Hammons received degrees in agricultural economics and finance from Oklahoma State University.

Hammons is the membership chair for the Kansas and Western District of Missouri chapter Federal Bar Association, a member of the American Bar Association, the American Agricultural Law Association, and the Foundation for Natural Resources and Energy Law, and is the secretary for the Oklahoma State University Alumni Association – Kansas City chapter. Since 2021, Hammons has also co-authored the Kansas Chapter of the American Bar Association’s The Law of Class Action: Fifty-State Survey.

Recent Cases

Settlements

  • Cook Children’s Health Foundation v. Diamondback E&P, LLC, No. CIV-21-359 (W.D. Okla.) (part of team that secured $12 million settlement for alleged breach of off-lease use of gas royalty clause for royalty owners in Texas wells)
  • Sagacity, Inc. v. Cimarex Energy Co., No. CIV-17-101 (E.D. Okla.) (part of team that secured combined $20.5 million class action settlement alleged underpayment of royalties)
  • Radcliff v. Southern Star Cent. Gas Pipeline, Inc., No. 23-cv-00909-J (W.D. Okla.) (lead counsel securing confidential settlement for clients related to nuisance, negligence, and property damage associated with natural gas flaring)
  • CTF, Ltd., et al v. Encino Energy, LLC, et al., No. CJ-2018-26-A (Beaver Cty., Okla.) (part of team that secured $6.4 million trial judgment for underpayment of oil and gas royalties)
  • Hoog v. PetroQuest Energy, LLC, No. 16-cv-00463 (E.D. Okla.) (part of team that secured $45 million class action settlement for alleged underpayment of gas royalties)

Published Cases

  • Spence v. American Airlines, Inc., No. 23-cv-00552-O, 2025 WL 225127 (N.D. Tex. Jan. 10, 2025) (findings of facts and conclusions of law supporting Plaintiffs’ claims that Defendants breached fiduciary duty of loyalty)
  • Spence v. American Airlines, Inc., No. 23-cv-00552-O, 2024 WL 3092453 (N.D. Tex. June 20, 2024) (order denying Defendants’ motion for summary judgment)
  • Spence v. American Airlines, Inc., No. 23-cv-00552-O, ECF No. 122 (N.D. Tex. May 22, 2024) (order granting class certification) 
  • Carl v. Hilcorp Energy Co., 689 S.W.3d 894 (Tex. 2024) (certified question before Supreme Court of Texas related to market value of gas at the well used off lease)
  • Spence v. American Airlines, Inc., No. 23-cv-00552-O, 2024 WL 733640 (N.D. Tex. Feb. 21, 2024) (order denying motion to dismiss). 
Admissions & Qualifications
  • Kansas
  • Missouri
  • Oklahoma
  • Texas
  • U.S. District Court, District of Kansas
  • U.S. District Court, Western District of Missouri
  • U.S. District Court, Western District of Oklahoma
  • U.S. District Court, Eastern District of Oklahoma
  • U.S. District Court, Northern District of Oklahoma
  • U.S. Court of Appeal for the Fifth Circuit
  • U.S. Court of Appeal for the Tenth Circuit
Distinctions
  • American Jurisprudence Award (highest grade): 
    • Torts II
  • Best Lawyers: Ones to Watch – Mass Tort Litigation/Class Actions – Plaintiffs (2025)
  • Oklahoma Law Review
    • Published Author and Editorial Board Member
  • Oklahoma State University
    • Homecoming Executive Committee – Executive Director
    • Outstanding Senior (one of 14 selected university-wide for the class of 2018)
    • Senior of Distinction (awarded to top 1% of college of agriculture graduates)
    • Senior of Significance (awarded to top 1% of class of 2018)
    • Truman Scholarship – Institutional Nominee
Professional Memberships
  • American Bar Association 
    • Young Lawyers Division; Litigation Section
  • American Agricultural Law Association 
  • Earl E. O’Connor American Inn of Court
    • 2022-23: Mentorship Committee
  • Federal Bar Association – Kansas and Western District of Missouri Chapter
    • 2022-Present: Membership Chair
  • Kansas Bar Association 
    • 2022-23: Membership Committee
    • 2023-24: Young Lawyer Section – Social Committee Co-Vice Chair 
  • Kansas City Metropolitan Bar Association
    • Ross. T. Roberts Trial Academy – 2022-2023
    • Bar Leadership Academy – 2024-2025 
  • Oklahoma Bar Association
  • Oklahoma State University Alumni Association
    • Kansas City Metro Area – Board Member
    • Life Member
  • The Foundation for Natural Resources and Energy Law
  • The Sirloin Club of Oklahoma
Selected Publications
  • Author, Survey on State Class Action Law (Kansas), American Bar Association, 2021-Present 
  • The Shifting Definition: The Clean Water Act, Waters of the United States, and the Impact on Agriculture, 73 Okla. L. Rev. 337 (2021).