The unions, liberal interest groups, and their academic allies tried to defund the right by getting the SEC to require disclosure of political campaign donations by corporations. Marc Hodak remarks that:
New SEC Chairpersons tend to bring along new priorities. Mary Shapiro, former FINRA regulator, brought a strong regulatory agenda. Mary Jo White, former United States Attorney, is bringing a strong prosecutorial agenda. This shift in priorities appears to have manifested itself in a new Rule List that, at least for now, drops the push for disclosure of corporate political contributions. The pro-regulatory crowd is not going to be happy. ...
Corporate political spending has been a hot topic since Citizens United in 2010. This ruling gave corporations and unions the ability to spend without limit on political ads, as long as they did not directly contribute to a candidate’s campaign. The people pushing hardest for corporate disclosure of such spending have—no surprise—been those most opposed the policies that corporations are most likely to promote, e.g., less regulation, lower taxes, and reduced trade barriers.
Thankfully the SEC decided that its mandate didn't extend to giving liberals a leg up in the political arena.