David Siegel is a computer scientist and co-founder of Two Sigma, the New York quantitative investment firm, where he has been co-chairman since stepping down as co-chief executive in September 2024.
David Siegel is a computer scientist and co-founder of Two Sigma, the New York quantitative investment firm, where he has been co-chairman since stepping down as co-chief executive in September 2024.
Siegel was born in the Bronx in 1961. He studied electrical engineering and computer science at Princeton University and earned a PhD in computer science at MIT, where he worked at the Artificial Intelligence Laboratory. He was the first chief information officer at D.E. Shaw & Co., founded FarSight Financial Services, which Merrill Lynch later acquired, and was chief technology officer and a managing director at Tudor Investment Corporation. In 1999 he founded Blink.com, a bookmarking service.
He co-founded Two Sigma in 2001 with John Overdeck. The firm applies data and computing to investing, and its largest business is a hedge fund; it manages more than $75 billion. Two Sigma Investments, LP's 13F for June 2026 listed about $138 billion of US-listed securities, including options. In August 2024 Siegel and Overdeck said they would step down as co-CEOs, handing the role to Carter Lyons and Scott Hoffman on 30 September 2024, while staying on as co-chairmen.
The two founders have since disagreed over how the firm is run, and Two Sigma has described the dispute as a material risk in regulatory filings. Hoffman resigned in early 2026, citing governance challenges. In March 2026 Siegel designated Seth Platt as his executive manager on the firm's two-person management committee; whether Platt also became co-CEO, and his move to remove Lyons, went to dispute resolution, according to the firm's Form ADV. In October 2026 Platt said he would leave once a successor is named. Siegel's family office has said he does not plan to return to day-to-day management.
Outside the firm, Siegel founded the Siegel Family Endowment in 2011 and co-founded the Scratch Foundation in 2014, where he is vice chairman. He sits on the MIT Corporation's executive committee and chairs the Board of Overseers at Cornell Tech. Forbes put his net worth at about $9.3 billion in October 2026.
Sources · written 23 October 2026