The Philanthropy Roundtable filed an amicus brief Friday in a case challenging the California attorney general’s requirement that nonprofits disclose major donors in their annual registration filings. The 34-page brief was filed Friday in Americans for Prosperity Foundation v. Becerra. The roundtable asks the U.S. Court of Appeals for the 9th Circuit to uphold a federal district court’s earlier ruling that the attorney general’s office attempt to force nonprofits to disclose donor lists is an unconstitutional burden on its 1st Amendment rights.