DENVER – Opponents of some Obama-era oil and gas regulations say a decision by a federal appeals court in Denver could allow those rules to go into effect temporarily, even though the Trump administration plans to revoke them.

Four states, two industry groups and a Native American tribe filed documents Friday and Monday asking the 10th U.S. Circuit Court of Appeals to reconsider a decision it issued in September.

That decision said it would be a waste of time to rule on whether the regulations are legal because the new administration has already begun to overturn them. But the decision cast doubt on whether the regulations are in force in the meantime.

Colorado, North Dakota, Utah and Wyoming asked the court reconsider. Two industry groups – the Independent Petroleum Association of America and the Western Energy Alliance – filed another request, as did the Ute Indian Tribe of the Uintah and Ouray Reservation in Utah.

The industry groups said that unless the September decision is changed, the federal government could be forced to enact the rules until they are formally revoked. Energy companies would have to spend time and money complying or risk getting sued, the groups said.

The Ute tribe said it would suffer economic losses if the rules take effect because energy companies might hold off drilling on tribal land until the Trump administration revokes them. The states said they too would be harmed.

The appeals court did not immediately say whether it would reconsider. It told six environmental groups that are parties to the case to respond to the requests by Nov. 20.

The 2015 rules require drilling companies to disclose what chemicals they used in hydraulic fracturing on federal and tribal land. Hydraulic fracturing boosts oil and gas production by injecting a high-pressure mix of water, sand and chemicals underground to break open rock formations.

A federal judge in Wyoming overturned the regulations last year, saying the government had no authority to impose them. The Obama administration – which was still in office – and environmentalists appealed.

Before the appeals court could rule, the Trump administration took office and announced it would revoke the regulations. That process is underway but not yet complete.

The 10th Circuit, citing the uncertain future of the regulations, dismissed the appeals in its September decision but also reversed the Wyoming judge’s decision that overturned the regulations in the first place. That left confusion about whether the regulations are in force.