On July 29, 2025, EPA proposed that the Clean Air Act (CAA) does not authorize the agency to promulgate greenhouse gas (GHG) emission standards to address climate change, thereby rescinding EPA's 2009 "Endangerment Finding" that GHG emissions contribute to air pollution endangering public health or welfare. In doing so, EPA is proposing to repeal all GHG standards for passenger vehicles and trucks in the United States.

EPA's proposal to repeal the Endangerment Finding represents the single most comprehensive attempt to deregulate GHGs at the federal level taken to date. Administrator Zeldin characterized the proposed rule as "the largest deregulatory action in the history of America." The 2009 Endangerment Finding established that emissions of six GHGs (including carbon dioxide and methan

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