The U.S. Supreme Court determined that it would decline to review a ruling that invalidated an Environmental Protection Agency (EPA) rule banning hydrofluorocarbons. Environmental groups and two companies sought review of a U.S. Court of Appeals for the District of Columbia Circuit decision vacating portions of a 2015 rule under Title VI of the Clean Air Act that prohibited the use of hydrofluorocarbons because they are greenhouse gases (GHGs). Title VI, the court ruled, gave EPA the power only to ban chemicals that deplete ozone, not because they are greenhouse gases. Because the hydrofluorocarbons subject to the rule had no ozone-depleting potential, EPA lacked the power under the Clean Air Act to ban them as GHGs. The Department of Justice urged the Supreme Court to deny certiorari, stating that the ruling below was correct.