Mealey's (July 11, 2016, 8:12 AM EDT) -- DENVER — A man who has filed several qui tam lawsuits against a group of gas companies for allegedly mismeasuring the volume of natural gas and providing wrongful analysis of its heating content as part of a plan to substantially underpay royalties to the U.S. government on July 6 filed a brief in the 10th Circuit U.S. Court of Appeals contending that his case is not frivolous or “clearly vexatious;” rather, he says, evidence supports his claim of fraud (In re: Natural Gas Royalties Qui Tam Litigation, No. 15-8054, 10th Cir.)....