Some of fracking’s biggest skeptics are on Wall Street. They argue that the industry’s financial foundation is unstable: Frackers haven’t proven that they can make money. “The industry has a very bad history of money going into it and never coming out,” says the hedge fund manager Jim Chanos, who founded one of the world’s largest short-selling hedge funds. The 60 biggest exploration and production firms are not generating enough cash from their operations to cover their operating and capital expenses. In aggregate, from mid-2012 to mid-2017, they had negative free cash flow of $9 billion per quarter.