[3] He and his wife Janine Yass are supporters of school choice, a cause to which they have donated tens of millions of dollars.
[5] He is the co-founder and managing director of the Philadelphia-based trading and technology firm Susquehanna International Group (SIG) and a major investor in TikTok.
[10] Yass was born in 1958 in Queens, New York City, and grew up there in a middle-class Jewish family.
While at the State University of New York at Binghamton in the 1970s, Yass and five fellow students became friends and later co-founded Susquehanna International Group (SIG), the largest trader of liquid stocks in the US.
[13][21] In the 1970s and early 1980s, before establishing his trading firm, Yass was a professional gambler, winning sums from poker and horse betting.
[13] As of 2021, SIG generates almost one-tenth of the market making trade volume in exchange-traded funds.
In 2015, Yass donated $2.3 million to a super PAC supporting Rand Paul's presidential candidacy.
[26] He donated approximately $100M during the 2024 US election cycle to Republican groups and campaigns,[27] including $6 million in political contributions via the Commonwealth Leaders Fund PAC, supporting Republican Dave Sunday over Democrat Eugene DePasquale in the 2024 Pennsylvania Attorney General election.
[28] In March 2021, the Israeli newspaper Haaretz reported that Jeff Yass and Arthur Dantchik were behind a large portion of the donations to the Kohelet Policy Forum in Israel.
[29] In April 2024, The Guardian reported that Jeff Yass donated $16 million to anti-Muslim and pro-Israel groups.
[40] In December 2001, following the aftermath of the September 11 attacks, he announced a donation to the charitable fund established by the Port Authority of New York and New Jersey to assist the victims.