It has been said that possession is nine-tenths of the law. Recently the Pennsylvania Supreme Court agreed to hear the appeal of a case that involves the other one-tenth, which seems unremarkable enough. Except that this one-tenth has the potential to affect hundreds of millions of dollars’ worth of oil and gas leases in Pennsylvania.

In 1881, Charles Powers possessed a large tract of land in Susquehanna County. He wanted to sell it, but to keep the right to some of the value hidden below the surface. He executed a deed that forever reserved for himself and his heirs “one half of the minerals and Petroleum Oils on the property.”