States, environmental groups, and industry representatives challenged the EPA's announcement that it would reconsider the appropriateness of, and conduct a rulemaking to potentially alter, greenhouse gas emission standards adopted in 2012 for model year 2022 to 2025 motor vehicles (Revised Determination).

The DC Circuit dismissed the petitions for review based on lack of jurisdiction, holding that the EPA has not engaged in final action under the Clean Air Act. The court held that the Revised Determination was akin to an agency's grant of a petition for reconsideration of a rule. In this case, the Revised Determination neither determines rights or obligations or imposes any legal consequences, nor alters the baseline upon which any departure from the currently effective 2012 emission standards must be explained.

Read the attached decision.