The U.S. Environmental Protection Agency (EPA) yesterday announced its intent to rescind the 2009 Endangerment and Cause or Contribute Finding for Greenhouse Gases (the Finding) later this week. The Finding, issued under the Clean Air Act (the Act) and preceded by confirmation of the EPA’s regulatory authority by the U.S. Supreme Court in a landmark 2007 decision, has served as the legal foundation for almost all climate regulations under the Act, including auto standards. Once rescinded, the EPA is expected to repeal all GHG emission standards for light-, medium-, and heavy-duty vehicles and engines. The EPA previously indicated that engine and vehicle manufacturers would no longer have any future obligations for the measurement, control, and reporting of GHG emissions for any highway engine and vehicle. The EPA has stated, however, that it would maintain regulations necessary for criteria pollutant and air toxic measurement and standards, Corporate Average Fuel Economy testing, and associated fuel economy labeling requirements. Background. On December 7, 2009, the Obama Administration signed two distinct findings regarding GHGs under section 202(a) of the Act: Endangerment Finding. Current and projected concentrations of the six key well-mixed greenhouse gases – carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6) – in the atmosphere threaten the public health and welfare of current and future generations. Cause or Contribute Finding. The combined emissions of the well-mixed GHGs from new motor vehicles and new motor vehicle engines contribute to the GHG pollution that threatens public health and welfare. On January 20, 2025, President Trump signed an Executive Order directing the EPA to submit recommendations regarding the legality and continuing applicability of the Finding. Following that directive, the EPA announced last summer that it was reconsidering the Finding, culminating in this week’s anticipated formal rescinding of the Finding.   For further information or to discuss the contents…