Billionaire conservative megadonor Charles Koch is backing a group behind a Supreme Court case seeking to keep charitable donations secret

The case features a petition from a charitable nonprofit, the Americans for Prosperity Foundation (AFPF), and amicus briefs from 22 other groups. AFPF and 15 of the amicus brief filers have received more than $35.3 million from Koch family foundations and two donor-advised funds known to be used by the Koch family since 2015, according to an analysis of IRS tax records by the Center for Media and Democracy. (AFPF is connected to the Charles Koch-backed Americans for Prosperity, or AFP.)