On 8 February 2022, the US Court of Appeals for the Tenth Circuit ruled that the climate change lawsuit filed by Boulder County, San Miguel County, and the City of Boulder against ExxonMobil and Suncor can proceed in state court rather than federal court. The plaintiffs accuse the companies of climate change-related harm and ask them to pay to adapt their infrastructure to climate disasters.

The judge dismissed the companies' arguments, among others, that "the case is inherently federal because the Clean Air Act displaces state law."

According to EarthRights International, this decision sets a precedent for similar cases that have been filed in the US.

Exxon's spokesperson said that lawsuit is "wast(ing) millions of dollars of taxpayer money and do(ing) nothing to advance meaningful actions that reduce the risks of climate change."

In March 2023, the federal government field a brief on behalf of Coloradon communities pushing for the case to be held in state court. Six federal appellate courts unanimously agree the case should be tried at the state level, but Exxon and Suncor want it to be held at the federal level, where communities have fewer remedies. The oil companies sought review from the Supreme Court. If the Court declines review, the case will proceed at the state level.

In April 2023, the Supreme Court declined Exxon and Suncor's petition. The case will now proceed in state court.

As of May 2023, the Supreme Court declined seven petitions from energy companies across the company to move climate change litigation cases to the federal level.