Several big hedge funds that stand to win billions of dollars for their shares in Fannie Mae and Freddie Mac are said to be backing new investors' rights groups airing attacks ads and statements against the Johnson-Crapo housing finance reform legislation. Hedge fund managers oppose the legislation because it would codify a contentious 2012 change to the terms of Fannie and Freddie shareholders' agreement in which Treasury imposed a sweep on all GSE shareholder company profits. Investors are currently fighting that action in more than a dozen lawsuits. Although the advocacy groups portray themselves as working for smaller investors, the anonymous nature of contributions has led to speculation that hedge funds are financing the operations.