Polymarket Founder Pushes Back on Insider Trading Concerns

Polymarket founder and CEO Shayne Coplan took the stage at Harvard on Monday, dismissing the notion that prediction markets could corrupt sports, adding that concerns over sporting integrity and insider trading were “outlandish and baseless.” 

Coplan was responding to a pointed hypothetical posed by Harvard Law professor Jonathan Zittrain, who raised the possibility of an athlete deliberately losing a game to profit from a prediction market bet. Coplan's rebuttal centered on the dollar figures involved.  

Coplan described this as trivial when compared to the leverage available in oil futures or equity markets. The financial incentive to fix a game on prediction market apps simply does not pencil out at that scale. 

Coplan also used the appearance to take aim at the established legal sportsbook model, arguing that traditional operators track betting histories and restrict winning customers. Polymarket's blockchain infrastructure, he noted, makes every wallet and position publicly visible to regulators. 

That transparency argument has its limits, however. Spain's gambling authority blocked Polymarket and rival platform Kalshi this past Tuesday, citing unlicensed operations and the absence of identity verification standards. The regulator also flagged inadequate protections for minors and self-excluded users. The suspension is expected to last three to four months.  

Meanwhile, scrutiny is building in Washington. House Oversight Chairman James Comer opened a congressional investigation into potential insider trading on prediction platforms after a military officer allegedly cleared $400,000 on a bet tied to US military action in Venezuela. The Justice Department has since filed charges in that case. The soldier has pleaded not guilty. 

At the same time, Polymarket is currently in talks to raise funding at a reported $15 billion valuation despite the pressure. 

Polymarket moves into private company territory

The regulatory heat surrounding Polymarket has done little to slow the platform's product ambitions. Earlier this month, the company announced a partnership with Nasdaq Private Market that extends its prediction contracts beyond public events and into the world of private companies for the first time. 

Starting May 19, users can trade contracts tied to valuation milestones, anticipated IPO timelines, and secondary market activity for select private firms. Nasdaq Private Market, which operates as a secondary trading venue and tracks data on non-public companies, is supplying the underlying information that makes those contracts possible. Additional markets are being added on a rolling basis. 

The structure follows Polymarket's established format: participants take positions on binary yes-or-no outcomes rather than purchasing equity or debt. The idea is that someone could take a position on a company's trajectory before it ever files for an IPO. 

Competitor Kalshi already offers contracts on whether companies such as SpaceX and OpenAI will announce public listings, so Polymarket's move narrows what had been a product gap between the two platforms.