The Federal Election Commission may unmask the identities of a mystery political donor and trust, known only in public documents as John Doe 1 and John Doe 2, a federal appeals court said Friday.

The case stretches back to an October 2012 $1.71 million donation that ultimately went to a super PAC that at the time supported Missouri Senate candidate Todd Akin, a Republican who ran unsuccessfully against Democrat and then-Sen. Claire McCaskill. Akin was widely criticized for saying women who are victims of “legitimate rape” were unlikely to become pregnant.

“We see this as a big victory for transparency,” said Jordan Libowitz, a spokesman for Citizens for Responsibility and Ethics in Washington, a watchdog group that first lodged a complaint in 2015. “These things tend to take a long time.”

It still may take months, if not longer, before the name of the donor is public as well as the trust used to make the donation, which passed through the American Conservative Union before going to the Now or Never PAC, which FEC documents show has since been shuttered. The U.S. Court of Appeals for the D.C. Circuit decided the case Friday and released a redacted opinion.

The appeals court agreed with a lower court that the FEC may disclose the information, though the John Does may appeal Friday’s decision. A lawyer for the John Does, John P. Elwood of Vinson & Elkins, did not respond to an email or phone call seeking comment.

The John Does “claim that disclosing their identity would ‘chill’ them from engaging in political activity. But this does not distinguish them from others who make campaign contributions. And in any event, the Supreme Court rejected just such a claim of ‘chill’ in Citizens United,” the court wrote, referring to the 2010 landmark decision, Citizens United v. FEC, which helped pave the way for super PACs.

Such PACs can raise and spend unlimited amounts of money from individuals and corporations, but they are not permitted to coordinate electioneering with candidates whom they support or oppose. Super PACs do disclose their donors.

In this case, CREW alleged the John Does worked to keep their identities unknown by giving through the ACU. The ACU did not respond to a request seeking comment, but the group agreed in 2017 to pay a $350,000 fine stemming from its role in the case.

The appeals court dismissed the John Does’ arguments for keeping their identities private, saying they did not qualify for exemptions.

“Information relating to business judgments and relationships does not qualify for exemption,” the court wrote in the Friday opinion. “This is so even if disclosure might tarnish someone’s professional reputation.”

Ellen Weintraub, who currently chairs the FEC, said in December 2017 that the case served as “an egregious example of someone using a web of organizations to hide the true source of a $1.7 million contribution to a super PAC — and getting away with it.”

CREW Executive Director Noah Bookbinder added: “This is one of the clearest cases we’ve seen of laundering money through a dark money nonprofit to conceal the source of a political contribution.”