The summary of the holding from the court’s opinion:
[W]e conclude: 1) the Endangerment Finding and Tailpipe Rule are neither arbitrary nor capricious; 2) EPA’s interpretation of the governing CAA provisions is unambiguously correct; and 3) no petitioner has standing to challenge the Timing and Tailoring Rules. We thus dismiss for lack of jurisdiction all petitions for review of the Timing and Tailoring Rules, and deny the remainder of the petitions.
The opinion is available here. The court simultaneously ordered the Clerk, consistent with D.C. Circuit Rule 41(b), to “withhold issuance of the mandate herein until seven days after disposition of any timely petition for rehearing or petition for rehearing en banc.”