Background and Procedural Posture

This appeal arises from a trespass action brought by oil and gas lessor Elton Goodwin against XTO Energy Inc. concerning subsurface wellbore intrusions on Goodwin's property in San Augustine County. The 273rd Judicial District Court granted partial summary judgment to Goodwin on the trespass claim and, following a jury trial, entered judgment in his favor. XTO appealed multiple aspects of the trial court's rulings, including the recognition of subsurface trespass, the admission and sufficiency of damages evidence, alleged breaches of implied covenants, and XTO's unjust enrichment counterclaim.

Subsurface Trespass: Ownership Rights at Depth

The Tyler Court of Appeals affirmed that Goodwin possessed a legally protected ownership interest in the subsurface of his property at the depth of XTO's cased wellbore intrusion. Applying foundational property principles, the court emphasized that

"The surface overlying a leased mineral estate is the surface owner's property, and those ownership rights include the geological structures beneath the surface."

The court further clarified that

"the surface owner, not the mineral owner, owns all non-mineral molecules of the land, that is, the mass that undergirds the surface estate."

This holding reaffirms that unauthorized subsurface intrusions—even by cased wellbores that do not extract minerals from the trespassed property—constitute actionable trespass regardless of the depth at which the intrusion occurs.

Damages Evidence: Reliability Standards for Expert Testimony

Despite affirming the trespass liability, the court reversed the damages award, finding the expert testimony legally insufficient under Texas Rule of Evidence 702. Goodwin's expert had calculated damages based on values XTO projected in its SEC filings for the wellbore. The court held this methodology fundamentally flawed, finding that the expert's testimony was unreliable and thus constituted legally no evidence to support the damages verdict. The expert assumed as true that the wellbore had the value projected by XTO in its Securities and Exchange Commission filings, which was unwarranted as the values were merely a forecast and were not supported by reliable data, and no evidence of actual production from the wellbore intrusion was presented. The court emphasized that expert opinion testimony on damages must be supported by objective facts, figures, or data from which the amount may be ascertained with reasonable certainty, and that unreliable expert testimony constitutes legally no evidence.

Implied Covenant to Protect Against Drainage

The court rejected Goodwin's claim that XTO breached an implied duty to prevent drainage from his tracts. The court held that XTO did not have any implied duty to prevent potential drainage from Goodwin's tracts from wells drilled on adjoining non-owned leased properties.

Voluntary Payment Rule Bars Unjust Enrichment Claim

The court applied the voluntary payment rule to preclude XTO's unjust enrichment counterclaim. XTO had sought recovery of payments made to Goodwin, but the court held that the voluntary payment rule barred this claim.