Schwartzenberger v. Hunt Trust Estate

The Schwartzenbergers (plaintiffs) leased oil and gas rights to Trust Estate (defendant) under a lease requiring drilling within one year or payment of a per-acre delay rental to avoid termination. During negotiations, Mr. Schwartzenberger mistakenly understated the leased acreage, and Trust Estate, without checking the deed, calculated and paid its delay rental based on that mistaken, smaller acreage rather than the property's actual size when it failed to drill within the year. After the Schwartzenbergers pointed out the shortfall, Trust Estate denied owing the difference; the Schwartzenbergers then gave notice terminating the lease, but Trust Estate never filed a release. The Schwartzenbergers sued for a judgment that the lease had terminated, and the trial court instead reformed the lease for mutual mistake, keeping it in effect so long as Trust Estate paid the deficient rental amount; the Schwartzenbergers appealed.