Who is Jeff Yass? The billionaire donor with investments in TikTok’s parent company

In the pitched battle between TikTok and Washington, few people stand to lose more than Jeff Yass, an American billionaire options trader who has emerged in recent years as a major donor to Republican candidates and causes. 

Yass co-founded the Philadelphia-based trading firm Susquehanna International Group, which owns a 15% stake in TikTok's China-based parent company, ByteDance. Yass' personal share is 7%, worth roughly $21 billion.

Yass' investment is under threat today, and the typicallypress-shy billionaire is taking fire from both the left and the right. Critics accuse Yass of bankrolling an army of lobbyists and orchestrating a bare-knuckle pressure campaign to protect TikTok — including by leveraging his nascent relationship with former President Donald Trump.

Through a spokesperson, Yass declined to comment on this story.

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On Wednesday, the House is expected to pass bipartisan legislation that would force ByteDance to divest TikTok within a matter of months. President Joe Biden said that he would sign it into law if the bill wins Senate approval.

"It would be a gut punch to the valuation and future of TikTok if a ban and forced sale came to fruition," Dan Ives, a managing director and senior equity research analyst at Wedbush Securities, said in an email.

"This would be a nightmare for Yass, given the major investment in TikTok, if a forced ban hit the company under the Biden administration," Ives said. The impact would "likely be a