Stephen Luparello, director of the SEC's division of trading and markets, will leave the agency by Dec. 31.
Heather Seidel, the division's chief counsel, will become the acting director upon Mr. Luparello's departure, the Securities and Exchange Commission said Monday in a news release.
Mr. Luparello has been director of the SEC division since February 2014. He serves on the agency's Equity Market Structure Advisory Committee, which is reviewing U.S. stock market structure. The SEC also credited him with helping create Regulation Systems Compliance and Integrity, or Reg SCI, which requires equity trading venues to disclose their backup operational plans to the agency, and the consolidated audit trail database approved by the SEC Nov. 15.
Mr. Luparello's departure announcement comes one week after SEC Chairwoman Mary Jo White announced she would step down at the end of the Obama administration in January.