Since the first leases for drilling on the Marcellus Shale formation were sold in 2008, hundreds of millions of dollars of that revenue has been tapped to shore up the state's operating budgets under Corbett and Rendell. The foundation will continue to press an appeal on its argument that the leasing violates a state constitutional provision that says public natural resources are "the common property of all the people including generations yet to come" and that the state's role is to conserve and maintain them, Childe said. Wolf also campaigned on a pledge to seek legislative approval for a 5 percent extraction tax on natural gas to raise additional revenue for public schools and other programs.