Fraternity brothers at the University of Miami may have used insider knowledge about Jeff Bezos’ weekend plans to bet against his Super Bowl attendance on Kalshi’s celebrity attendance market.

According to a Wall Street Journal investigation published Thursday, the tip originated from within the fraternity, which counts Bezos’ stepson as a member, and spread by text to other campuses within days.

The odds of Bezos attending plummeted from 70% to under 30%.

“We know this shouldn’t be allowed,” one brother told the Journal. “It feels like someone should stop you.”

Kalshi told the Journal it is investigating the Bezos bets for possible insider trading.

Paying Frats To Sign Up Bettors

The insider trading is one symptom of a broader campus arms race. Polymarket paid a Columbia University fraternity $30,510 in two weeks through a referral program.

Some of that funded an “epic end-of-the-semester party.” The company also seeded a University of Chicago prediction markets club with $20,000.

Kalshi sponsored Duke Poker Club prize pools and a Yale hedge fund competition.

Both platforms have paid student influencers and athletes to promote betting on TikTok and Instagram, often without disclosing the sponsorship.

Because prediction markets are regulated as financial derivatives by the CFTC, users as young as 18 can trade.

Most state sportsbooks require bettors to be 21, giving Kalshi and Polymarket a three-year window to hook young users that DraftKings Inc (NASDAQ:DKNG) and Flutter Entertainment (NYSE:FLUT) cannot legally reach.

A Rivalry Turning Personal

NPR reported Friday that the feud between Kalshi CEO Tarek Mansour, 29, and Polymarket CEO Shayne Coplan, 27, has escalated.

Mansour reportedly refuses to say the word “Polymarket” in public. After the FBI raided Coplan’s apartment in 2024, Kalshi staffers promoted memes mocking him.

Both companies have filed competing trademark applications for “the world’s largest prediction market.” A former Kalshi employee called the rivalry “existential.”

When Kalshi gave away $50 in free groceries per shopper in New York’s East Village last month, Polymarket opened its own ‘free’ grocery store in Manhattan.

Why DKNG Is Watching

The campus gold rush matters for DraftKings, which is down over 30% year to date.

CEO Jason Robins has called prediction markets a $10 billion revenue opportunity, but DraftKings Predictions finished far behind Kalshi in Super Bowl app downloads.

Insider trading controversies are drawing increasing regulatory scrutiny, with multiple bills now moving through Congress to restrict prediction market trading by federal officials.

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