Former Sullivan & Cromwell partner Jay Clayton is returning to the Wall Street firm following his three-and-a-half-year term as chairman of the U.S. Securities and Exchange Commission, the firm announced Thursday.

Clayton, who was SEC chairman from May 2017 through December 2020, returns to Sullivan & Cromwell as a senior policy adviser and of counsel in its New York office. According to the firm’s announcement, he has also been appointed to the new role of lead independent director at private equity titan Apollo Global Management, and will also return to his role as adjunct professor at the University of Pennsylvania Carey Law School.