Who is Jeff Yass, Pennsylvania’s billionaire investor and political funder?

Jeff Yass, Main Line resident and the richest man in Pennsylvania, continues to draw attention for the millions he gives politicians and school causes from the multibillion-dollar fortune he made.

On Tuesday, the nonprofit newsroom ProPublica published an article recapping Yass’ career and the $100 million it says he has given politicians in recent years — including such failed efforts as a 2020 super-PAC campaign against Joe Biden, Democratic State Rep. Anthony Williams’ runs for top Pennsylvania and Philadelphia offices, and Andrew Yang’s bid for New York City mayor, and William McSwain’s bid for governor in Pennsylvania’s GOP primary last month.

ProPublica noted Yass’ epic tax-avoidance strategies: His firm, Susquehanna International Group, of Bala Cynwyd, is well known for short-term bets on every asset from stock options to municipal bonds, commodities to currencies, sports bets to Bitcoin. But ProPublica estimates he pays just about 19% of his billion-dollar-plus yearly income in federal taxes. That’s close to the U.S. rate for long-term capital gains but only about half the usual rate on high personal incomes. (There are billionaires who pay more, and less.)

» READ MORE: Meet the billionaire and rising GOP mega-donor who’s gaming the tax system

Yass, 63, is among the most successful of a coterie of proprietary traders — that means they bet their own money — who have become billionaires through fast, large trades and investment of the resulting flood of capital.

A longtime supporter of the Libertarian Party, Yass also champions private and charter schools, and has showered millions on politicians who agree to uphold these and other conservative causes. His school advocacy has drawn the ire of public-school teachers’ unions. His support for conservative groups in Israel has also made Yass a target of Jewish liberals, who have protested outside his office on City Avenue and his nearby home.

Forbes, in its annual list of the richest people, estimates Yass’ fortune at around $12 billion, citing his early investments in TikTok and other successful companies. ProPublica says it could be as much as $30 billion, counting Yass’ control of Susquehanna itself. It’s hard to value private assets, which might not be publicly appraised or sold for years.

The son of two New York accountants, Yass graduated the State University of New York at Binghamton and used the math he learned to bet on racehorses and poker. In 1987, with partners, he set up Susquehanna on the Philadelphia Stock Exchange (PHLX) options-trading floor — cheapest to join of the nation’s stock markets — later moving to Bala Cynwyd in Montgomery County, which offered lower labor and wealth taxes.

During Susquehanna’s first summer, Yass’ group bet the stock market was overpriced; they collected big when it crashed that fall. As Susquehanna grew, it added outposts in New York and around the world.

Yass and his colleagues focused first on stock and currency options trading, where money could be bet for a fraction of the shares’ value, with less up-front capital than traditional stock trading.

Susquehanna recruited chess masters, engineers, and math grads, and taught them to play casino poker, among other skills. Its traders became a fixture in the PHLX basement trading floor at 19th and Market Streets (now Nasdaq’s options business at Philadelphia’s FMC tower) before expanding worldwide.

Susquehanna and its rivals, such as Citadel Securities, Timber Hill, and King of Prussia-based Cooper Neff, became “market makers,” taking bets from other traders, as well as making their own. Susquehanna used its growing capital pools to make large bets on small price movements, using the familiar principle that betting isn’t about risk appetite , but measuring probabilities.

Starting in the late 1990s, Yass, his top partners, and a team of tech investors also began pouring the firm’s trading profits into private companies in the U.S., Southeast Asia, Europe, Israel, and especially China, where its best-known hit is ByteDance, the still-private company that owns TikTok, whose total value has been estimated at more than $50 billion.

Yass has backed a string of political losers. In 2016 he supported both Sen. Rand Paul (R., Ky.) and Libertarian Gary Johnson against Trump for President. People close to Yass say he took out bets on a European market against Trump’s 2020 reelection, and didn’t give Donald Trump money, but donated to anti-Biden efforts. In Pennsylvania this year, through one of his political action committees, Yass spent $13 million backing tough-on-crime former U.S. Attorney William McSwain for governor. As McSwain faded, the political committee Yass had funded switched to Lou Barletta, a former U.S. representative and anti-immigration and anti-tariff activist, who lost the GOP primary to State Sen. Doug Mastriano.

Forbes Magazine only began listing Yass among the richest Americans after TikTok’s 2020 disclosure that he had been a major investor. The company that summer planned an initial public offering (IPO). Yass stood to collect billions — until President Trump demanded American companies be given a controlling share. Oracle and Walmart stepped up to offer the needed capital, but the proposal got stuck in court. The company still hasn’t gone public, amid U.S. tensions with China.

Next, on Aug. 4, 2020 Yass gave $4 million to a political committee aligned with the conservative Club for Growth. Two days later, ProPublica reported, the group bought $5 million in ads attacking Trump’s Democratic rival, Biden, and announcing support for Yass’ pet cause, charter schools. In all, Yass has donated $32 million to the Club, which works to cut taxes on the rich, and millions more to PACs he controls.

Yass is a relentless supporter of privately managed education. He and his wife, Janine, have endowed the Yass Prize, formerly the STOP Award for Sustainable, Transformational Outstanding and Permissionless education, given to private, charter, and public school operators they believe orient children toward success.

In an email blast sent last month appealing for support, Janine Yass complained that charter school applications and private-school scholarship funding have been made “too difficult” by government. So, she explains, the prize plans to offer $10 million this year to charter and private schools, including a $1 million Yass Prize, which she calls “the Pulitzer Prize of education.”

Like many rich people, Yass and his partners have fought the Internal Revenue Service, paying over $121 million in a 2019 settlement after the Supreme Court refused an appeal.

According to ProPublica, an affiliate, Susquehanna Fundamental Investments, balances short-term trading gains with long-term losses to wipe out tax liabilities.

The IRS has questioned the strategy, according to ProPublica.