A McMullen County jury awarded $41.8 million against Energy Transfer affiliate ETC Field Services, LLC in 2023. Jurors determined that the company had trespassed on the subsurface mineral rights of two exploration and production companies, each of which held mineral leases in South Texas that the defendant’s injection operations had disrupted. Todd Mensing, litigator and AZA Law partner, served as lead trial counsel for SilverBow Resources, one of the two plaintiff companies. El Dorado Gas & Oil, Inc. was the second plaintiff, represented by co-counsel from Hogan Thompson. Mensing, a commercial litigator who has tried more than sixty cases in Texas courts, led an AZA team that included partners Taylor Freeman, Jane Robinson, and Cameron Byrd, along with associates Harrison Scheer, Hilary Greene, and Thomas Cooke.
Case No. M-14-0029-CV-C proceeded before Judge Janna Whatley in the 343rd District Court of McMullen County. The verdict ranked among the 15 largest in Texas that year. Later, the National Law Journal included it among the country’s top 100 verdicts for 2023.
What Oil and Gas Trespass Means in Texas
Trespass in oil and gas law differs materially from surface property disputes. Under Texas law, a subsurface trespass claim requires proof that a party entered, or caused something to enter, another party’s property without authorization, and that the unauthorized entry caused actual, cognizable injury.
Courts have repeatedly examined how Texas’s rule of capture interacts with trespass doctrine. Under that doctrine, a producer may capture oil and gas that has flowed from neighboring tracts into its own wells, without owing compensation to those neighboring landowners. That protection created decades of cover for producers who drained common formations through their own wells, and it raised persistent questions about where lawful production ends and actionable interference begins.
Subsurface injection cases occupy a different legal position. When a midstream operator introduces foreign material into the subsurface, the migrating substance is not oil or gas moving under natural geological pressure. It is material placed there by deliberate human action. Courts have recognized that the rule of capture does not shield a party from trespass liability simply because injected material later migrated underground. Liability can attach when injected material interferes with a lessee’s right to develop its own minerals.
Todd Mensing, a litigator who has won substantial verdicts in Texas energy disputes, built the SilverBow case around proving two core facts: that ETC Field Services’ injections physically entered the plaintiffs’ mineral estate, and that those injections measurably impaired each company’s production.
What the Plaintiffs Alleged
The dispute traces back to 2014, when surface and mineral rights owners in McMullen County sued Regency Field Services, a midstream company that Energy Transfer later acquired. Swift Energy Co., which renamed itself SilverBow Resources, intervened in 2015 with its own claims. El Dorado Gas & Oil, which also held acreage in the area, joined as a plaintiff alongside SilverBow.
At the core of the case was a specific factual claim: Energy Transfer operated an underground injection well and used it to dispose of hydrogen sulfide and carbon dioxide, the gaseous byproducts of natural gas processing. Both gases traveled farther through subsurface formations than Energy Transfer’s own predictive modeling had indicated. SilverBow and El Dorado contended the migration extended onto their leased acreage, disrupted planned drilling activity, and added costs to operations neither company had projected.
Proving that claim before a South Texas jury required precision at every stage. Todd Mensing, the lead litigator for SilverBow, had to establish the physical path of injected gas through subsurface formations, demonstrate that the migration overlapped with the plaintiffs’ mineral estate, and connect each dollar of claimed damages to a specific operational impact. Geological experts, petroleum engineers, and economic damage witnesses each played a defined role. Oil and gas trespass trials built around subsurface injection require expert testimony spanning geology, reservoir engineering, and economics, a combination that distinguishes them from standard commercial disputes.
Getting the Case to Trial
Before a single witness testified, the case had already moved through multiple appellate proceedings on the venue question. Energy Transfer sought to relocate the litigation out of McMullen County. After the 4th Court of Appeals in San Antonio declined to transfer venue, Energy Transfer filed a petition for writ of mandamus at the Texas Supreme Court in June 2017. Subsequent proceedings kept the case in McMullen County, where the disputed acreage sat, before Judge Janna Whatley in the 343rd District Court.
For Todd Mensing litigator and co-counsel from Hogan Thompson, the outcome of that venue fight shaped the terms for how the trial would unfold. Venue in oil and gas litigation affects jury composition, witness logistics, and which appellate court receives the trial record on appeal. McMullen County, located in the heart of South Texas oil country, placed the case before a jury with firsthand familiarity with the producing formations at issue.
The Verdict and Its Record
After deliberating in February 2023, the McMullen County jury awarded SilverBow Resources $24.5 million and El Dorado Gas & Oil $17.3 million, for a combined recovery of $41.8 million. Jurors found that ETC Field Services had violated both companies’ mineral development rights through its underground injection operations. AZA identified the result as among the 15 largest verdicts in Texas for 2023. The National Law Journal listed it among the country’s top 100 verdicts that year, and a second industry publication independently placed it on a parallel national list.
For Todd Mensing, a Texas litigator whose practice focuses on complex energy disputes, the result reflected what the case demanded from the beginning: scientific rigor presented in a form accessible to a lay jury, paired with a damages framework precise enough to withstand challenge on appeal. Subsurface injection claims require a trial team that can convert geological modeling data into concrete proof of interference. Most commercial litigation involves harm that is visible and documented at the surface; these cases require proving damage that accumulated underground, invisibly, over years of field operations.
After Trial
A verdict of this magnitude against a major midstream operator nearly always produces an appellate challenge. Energy Transfer’s pre-trial effort to move the case out of McMullen County, which reached the Texas Supreme Court in 2017, signaled a litigation posture that would persist beyond the jury’s decision. McMullen County verdicts appealing through the Texas court system fall within the jurisdiction of the 4th Court of Appeals in San Antonio, the same intermediate court that had declined to transfer venue before trial.
Mensing, a litigator whose courtroom experience extends into appellate proceedings, continued with the case as it moved beyond the trial court. Post-verdict litigation in oil and gas trespass cases commonly involves motions for new trial, challenges to damages methodology, and disputes over prejudgment interest, each a separate front that trial counsel must hold while the appellate record takes shape.
The SilverBow and El Dorado case offers a detailed account of what oil and gas trespass litigation looks like when a midstream operator’s subsurface activity intrudes on neighboring E&P rights. Energy companies using underground injection wells face exposure that cannot be fully measured during operations, and this case shows what that exposure looks like when plaintiffs have years to document and quantify it.
