As USX Corp. sees it, federal appellate courts should get out of the business of predicting state law and instead should certify questions to state supreme courts whenever a case hinges on an unanswered question of state law. In an unusual petition for certiorari, lawyers for USX are asking the U.S. Supreme Court to "implement a presumption in favor of certifying substantial unanswered questions of state law." The petition in USX Corp. v. Liberty Mutual Insurance Co. comes on the heels of a decision in June by the 3rd U.S. Circuit Court of Appeals that overturned a lower court's $2.2 million judgment in USX's favor. In reaching its decision, the 3rd Circuit predicted a question of Pennsylvania law and ruled that occupational asbestos exposure does not meet Pennsylvania's traditional definition of a workplace "accident," but instead must be treated as a "disease." But USX argues that, in doing so, the 3rd Circuit ignored a 1993 decision of the Pennsylvania Supreme Court and instead relied on a half-century-old decision of the Pennsylvania Superior Court.