The Supreme Court on Monday issued a significant ruling for ongoing legal battles around climate change by declining to hear oil giant Exxon Mobil’s appeal in its suit with the state of Massachusetts. In the appeal, the company was attempting to block the release of records of its knowledge of how burning fossil fuels changes the climate.

Massachusetts Attorney General Maura Healey filed suit against the company in 2016 alleging that Exxon, the world’s largest investor-owned oil company, violated state consumer protection rules and misled investors about the impacts of fossil fuels on climate change as well as risks of climate change to its business.

Today’s #SCOTUS victory clears the way for our office to investigate Exxon’s conduct toward consumers and investors. The public deserves answers from this company about what it knew about the impacts of burning fossil fuels, and when. https://t.co/BljXQzcY49 — Maura Healey (@MassAGO) January 7, 2019

The Massachusetts Supreme Judicial Court decided last April that Exxon would have to start turning over internal documents about its knowledge about the impacts of fossil fuel combustion on the global climate. Exxon appealed the decision to the Supreme Court, arguing that the Massachusetts attorney general doesn’t have jurisdiction to compel the company to release documents.

But the high court declined to hear the appeal — a blow to Exxon that may lead to more damaging revelations about the company. The company has not yet responded to a request for comment, but the company website says it has followed the scientific consensus on climate change.

Healy’s suit was filed after reporting from InsideClimate News and the Los Angeles Times in 2015 found that Exxon Mobil’s in-house scientists warned top executives that fossil fuels were leading to more greenhouse gases in the atmosphere that were warming the planet with research dating to 1977.

Despite this, the company publicly sowed doubt about whether humans could warm the planet through advertising campaigns, as well as funding think tanks and institutions that outright denied climate change was occurring.

The company has since changed its tune. Last year, Exxon announced it was backing a campaign for a carbon tax. But in exchange for a tax, the company wants immunity from lawsuits like the one Healy filed.

Among the other lawsuits the company is facing is one filed by New York Attorney General Barbara Underwood in October. Interestingly, the claim in that suit is that Exxon misled investors about the risks of future climate change regulations on its business.

Exxon is also a defendant in lawsuits initiated by several cities, one county, and a state alleging that the company contributed to climate change, which poses a public nuisance. The cases filed by the cities of San Francisco and Oakland were dismissed last year, but other suits are still underway.

Meanwhile, the Supreme Court is keeping a close eye on other climate change litigation. The court stepped in to pause the Juliana v. US lawsuit last year just before the trials was set to begin. The case involves children suing the federal government for undertaking policies that contribute to climate change. The Supreme Court’s stay was lifted last year, but now the trial is now under a temporary stay from the Ninth Circuit Court of Appeals. That court is hearing an appeal of the case from the US government.