Prediction Market Giants Polymarket and Kalshi Face Congressional Insider Trading Investigation

Table of Contents James Comer, who chairs the House Oversight Committee, is requesting comprehensive internal documentation from executives at two prominent prediction market platforms amid growing concerns that individuals with access to classified government information may be exploiting it for financial gain. LATEST: 🇺🇸 House Oversight Committee Chair James Comer has opened an insider trading probe into Kalshi and Polymarket, asking both CEOs to hand over records on identity checks and suspicious trade detection by June 5. pic.twitter.com/DPfGTFRKWR — CoinMarketCap (@CoinMarketCap) May 22, 2026 Correspondence dispatched on Friday to Shayne Coplan, Chief Executive of Polymarket, and Tarek Mansour, who leads Kalshi, requested comprehensive information regarding each platform’s user verification procedures, geographical access controls, and systems for detecting abnormal betting patterns. “Concerns have emerged that congressional representatives, administration officials, and any category of federal employee could leverage privileged insider information to generate substantial returns on government-related prediction markets,” Comer stated during an interview on CNBC’s Squawk Box. The investigation focuses on over 80 transactions identified as suspiciously coordinated with the timing of United States military operations directed at Iran. A May 13 investigation by The New York Times documented multiple instances involving wagers related to Israeli military actions against Iran, a ceasefire announcement from Trump, and political election markets. Nicolas Vaiman, who co-founded the blockchain intelligence platform Bubblemaps, revealed that his research team discovered 80 Polymarket transactions achieving a 98% profitability rate. “Pure chance cannot account for such consistent winning outcomes,” he stated. This congressional investigation emerged following criminal indictment proceedings initiated in April against Master Sergeant Gannon Ken Van Dyke of the United States Army. Federal prosecutors contend he exploited classified intelligence obtained from a military operation connected to Venezuelan President Nicolás Maduro, generating more than $400,000 in profits through Polymarket event contract trading. Van Dyke entered a not guilty plea to multiple charges, including commodities fraud and unauthorized disclosure of confidential governmental information. He secured release following posting of $250,000 bail. Both prediction market platforms rejected the allegations and defended their practices. Polymarket emphasized it “operates a thorough market integrity system” and pledged full cooperation with congressional investigators. Kalshi expressed pride in its “extensive safeguards preventing insider trading” and committed to working with legislative authorities. The House inquiry emerged merely 48 hours following a Senate Commerce Committee session during which legislators across party lines questioned prediction market platform representatives. Ted Cruz, chairing the Senate Commerce Committee, condemned the industry for facilitating cheating incidents within sports betting, while Senator John Hickenlooper accused these companies of predatory marketing tactics aimed at younger demographics through social media channels. Polymarket revised its insider trading prevention protocols in March. Kalshi prohibited three American political candidates from its platform in April after they wagered on their own electoral contests. Comer announced he may introduce legislative proposals specifically prohibiting congressional members, executive branch personnel, and additional government workers from engaging with prediction market platforms. According to research published by Wall Street firm Bernstein, prediction market trading volumes attained $51 billion during 2025, with projections indicating potential growth to $240 billion throughout 2026. Industry analysts forecast the sector could expand to approximately $1 trillion in total value by 2030. Vaiman cautioned that irregular trading patterns detectable by independent researchers remain equally visible to foreign adversaries of the United States, creating national security vulnerabilities extending beyond standard financial oversight considerations. Discover top-performing stocks in AI, Crypto, and Technology with expert analysis.