As part of building a transcontinental railroad, the Congress chartered the Union Pacific Railroad Company (U.P.) and gave it large portions of federally-owned land on either side of the planned route between Nebraska and Utah. In the late 1800s and early 1900s, the U.P. began to sell some of the land to farmers, ranchers, loggers and homesteaders via deeds that conveyed only the surface estate but retained the mineral rights to U.P. and a right of ingress and egress to prospect for, mine and remove minerals. When U.P. sought to exploit minerals on a particular tract, it would negotiate a "surface owners agreement" (SOA) with the owner of the surface estate and U.P. would pay the surface owner 2.5% of the value of minerals extracted. Around year 2000, the defendant acquired U.P.'s mineral interests with respect to the land at issue in the case. The defendant discontinued the practice of entering into an SOA with the landowners and ceased paying royalties to them as well. The plaintiffs (1,300 surface owners) sued, claiming that the defendant's use of the surface of their land exceeded the scope of the surface reservations in the deeds and that the defendant was committing a trespass. The plaintiffs moved for class certification. The court certified the class on a restricted basis simply to answer the question of whether the defendant exceeded the surface owner's rights by using vertical drilling rather than directional drilling because vertical drilling requires the drilling of more wells than would directional drilling. A-W Land Co., et al. v. Anadarko E&P Company LP, No. 09-cv-02293-MSK-MJW, 2015 U.S. Dist. LEXIS 95480 (D. Colo. Jul. 22, 2015).