Mark, a former chief of the New York office of the U.S. Securities and Exchange Commission’s Division of Broker-Dealer Enforcement, focuses his practice on complex securities-related litigation and enforcement. He has over 20 years' experience as a private practitioner representing investment banks, corporations, investment advisers, hedge funds, and directors and officers in many high-profile matters, from SEC, DOJ, state attorneys general and self regulatory organization investigations to national securities class actions.

Mark has consistently been involved in significant securities industry cases, including, among others, high frequency trading, the CDO investigations, structured and complex products investigations, the Squawk Box investigations, auction-rate securities, student loan investigations, options back-dating, NYSE and SEC specialist investigations, and the Salomon Brothers treasury bond investigation.