I have recently been reading "The Big Rich: the Rise and Fall of the Greatest Texas Oil Fortunes," by Bryan Burrough. It has reminded me of a fascinating chapter in the history of Texas oil and gas law that arose out of the Texas oil boom in the early years of the 20th century, and that still affects mineral titles to more than 7.4 million acres of land in Texas. It could also be seen as an early example of judicial activism in Texas.
Texas entered the Union retaining all of its public domain - all land not already sold by Spain or Mexico to private citizens. Under Spanish and Mexican laws, when the sovereign sold land it retained all mineral rights under those lands. When Texas became an independent nation, it recognized the titles of landowners who had acquired their lands by Spanish and Mexican grants, including the state's retention of mineral rights under those lands. In its constitution of 1876, Texas set aside more than 42,500,000 acres of unsold land as "public free school land," and provided that the sales of those lands would be set aside in a permanent fund to finance the provision of schools in Texas. That constitution also provided that the State released to the owners of lands previously sold "all mines and mineral substances" under their lands. This same provision was included as an article in the Revised Statutes of 1895. Thus, Texas decided that, unlike Spain and Mexico, it would not retain title to minerals under lands it sold for settlement and development.