Valley View Angus Ranch (Valley View) (plaintiff) was a 450-acre ranch on which Duke Energy Field Services (Duke) (defendant) possessed an easement. In an Oklahoma state court, Duke sued Valley View on the claim that Valley View had unlawfully restricted Duke from accessing the easement. A jury found in Duke’s favor. Valley View did not appeal. Valley View later filed a lawsuit against Duke in federal district court, alleging that Duke’s gas line through the easement had leaked, polluting the ranch’s soil and groundwater. Valley View sought damages for trespass, nuisance, and unjust enrichment. Duke moved for summary judgment, which the court granted on the ground that Valley View’s claims were barred by the earlier lawsuit. Valley View appealed.