On January 22, 1952, J.E. and Esther Eckhardt (defendants) conveyed a parcel of land to George and Yvonne Fransen (plaintiffs), but reserved a one-fourth interest in minerals in the land for 30 years and as long thereafter as minerals were “being produced from said land in paying quantities.” In September 1981, a well was completed on the land. On September 17, 1981, gas was determined to be available in paying quantities. In December 1981, the well operator signed a gas-purchase contract covering gas that was to be produced on the property. At that point, construction of a pipeline commenced, but the construction was not completed until April 1982. Gas was produced for the first time on May 5, 1982. The Fransens brought suit in state trial court to quiet title to the land, seeking a judgment that the Eckhardts’ term interest had expired on January 22, 1982. The Eckhardts removed the case to the United States District Court for the Western District of Oklahoma. The federal district court granted the Eckhardts’ motion for summary judgment. The United States Court of Appeals for the Tenth Circuit certified to the Supreme Court of Oklahoma the question of what constitutes production in paying quantities under a conveyed term mineral interest.