the government restoration. In 2004, Congress passed legislation to restore sovereignty to the Osage Nation and enable them to make their own decisions about government and membership qualifications for their people. In March 2010, the United States Court of Appeals for the Tenth Circuit held that the 1906 Allotment Act had disestablished the Osage reservation established in 1872. This ruling potentially affected the legal status of three of the seven Osage casinos, including the largest one in Tulsa, as it meant the casino was not on federal trust land. Federal Indian gaming law allows tribes to operate casinos only on trust land. The Osage Nation's largest economic enterprise, Osage Casinos, officially opened newly constructed casinos, hotels and convenience stores in Skiatook and Ponca City in December 2013. Natural resources and headrights Before having a vote within the tribe on the question of allotment, the Osage demanded that the government purge their tribal rolls of people who were not legally Osage. The Indian agent had been adding names of persons who were not approved by the tribe, and the Osage submitted a list of more than 400 persons to be investigated. Because the government removed few of the fraudulent people, the Osage had to share their land and oil rights with people who did not belong. But, the Osage had negotiated keeping communal control of the mineral rights. The act stated that all persons listed on tribal rolls prior to January 1, 1906 or born before July 1907 (allottees) would be allocated a share of the reservation's subsurface natural resources, regardless of blood quantum. The headright could be inherited by legal heirs. This communal claim to mineral resources was due to expire in 1926. After that, individual landowners would control the mineral rights to their plots. This provision heightened the pressure for those whites who were eager to gain control of Osage lands before the deadline. Although the Osage Allotment Act protected the tribe's mineral rights for two decades, any adult "of a sound mind" could sell surface land. In the time between 1907 and 1923, Osage individuals sold or leased thousands of acres to non-Indians of formerly restricted land. At the time, many Osage did not understand the value of such contracts and often were taken advantage of by unscrupulous businessmen, con artists, and others trying to grab part of their wealth. Non-Native Americans also tried to cash in on