Two Sigma co-founders John Overdeck and David Siegel decided to step down as Chief Executive Officers in August. : Hedge fund Two Sigma is likely to have to pay as much as $100 million to resolve a Securities and Exchange Commission probe into a trading scandal at the firm, the Wall Street Journal reported Thursday. The hedge fund is likely to be held accountable for how it oversaw an ex-employee at the center of the misconduct, which led to hundreds of millions of dollars in unexplained losses and profits, the report added citing people familiar with the matter.