Supreme Court Justice Samuel Alito recused himself Monday from a major climate-change case after facing calls to step aside due to stock holdings in oil companies.

A letter posted in the case did not specify a reason, but the conservative justice has previously recused himself from other cases involving companies where he holds stock.

“Justice Alito has determined that he will not continue to participate in this case,” the letter reads.

The recusal comes shortly before the court hears the case filed by local officials in Boulder, Colorado, against Suncor Energy and ExxonMobil. It’s one of dozens of similar cases alleging companies deceived the public about how fossil fuels contribute to climate change. Billions of dollars in damages could be at stake.

The high court agreed to hear an appeal from the companies, backed by the Trump administration.

The energy companies argue the lawsuits pose a serious threat to the industry and that state courts aren’t the right place to deal with the global issue of climate change.