The U.S. Court of Appeals for the District of Columbia Circuit has denied a petition filed by Honeywell, The Chemours Co., and the National Resources Defense Council (NRDC). The petition had asked the court to review its August 2017 decision in an appeal brought by Mexichem Fluor and Arkema (Mexichem Fluor Inc. vs. the Environmental Protection Agency). In that appeal, the court ruled 2-1 that the EPA cannot ban HFCs under Section 612 of the Clean Air Act because that provision was designed only to address ozone-depleting substances.