Polymarket referred dozens of accounts showing potential military insider trading to the Department of Justice before outside researchers recently publicly identified suspicious betting activity on war-related markets, CNN first reported.
The disclosure is a test of Polymarket’s integrity posture at a time when prediction markets face mounting questions about whether they can prevent users with access to nonpublic government information from turning that information into trading profits.
The company itself has not been accused of wrongdoing. Still, CNN’s report arrives after a DOJ prosecution involving a U.S. soldier’s alleged use of classified information for Polymarket wagers and an ongoing Commodity Futures Trading Commission investigation into the platform.
What Polymarket flagged
The referrals predated an analysis by the nonpartisan Anti-Corruption Data Collective, which identified 152 accounts that earned about $8 million across war-related markets, including markets tied to the Iran conflict, and found multiple indicators of possible insider activity.
According to CNN, Polymarket uses internal surveillance tools that monitor approximately 150 additional signals and trading patterns to look for suspicious activity.
The company did not publicly detail those indicators, which is unsurprising given that releasing them could help traders evade detection.
A response to scrutiny
The timing is not accidental, as Polymarket has already faced a Commodity Futures Trading Commission investigation, congressional scrutiny over prediction-market insider trading, and political blowback from reports that it paid creators to post videos of fabricated betting wins.
The platform’s decision to send cases to the DOJ suggests it is not waiting for outside reports or regulators to identify every potentially compromised market. Still, referrals after suspicious activity occurs are not the same as stopping a trade before it happens, particularly where national security information may be involved.
That distinction will matter for policymakers. The DOJ’s April indictment of Army soldier Gannon Ken Van Dyke alleged he used classified, nonpublic military information to make profitable Polymarket bets, charging him with commodities fraud, wire fraud, theft of nonpublic government information and other offenses.
Kalshi’s monitoring contrast
Kalshi has spent much of 2026 publicly building out its own integrity infrastructure. In February, it announced an independent surveillance advisory committee, a head of enforcement, expanded third-party monitoring and a relationship with the Wharton Forensic Analytics Lab.
Kalshi said it had conducted more than 200 investigations, frozen relevant accounts and referred several matters to law enforcement.
In June, Kalshi added market risk scoring, employment verification for traders in certain high-risk markets, enhanced whistleblower reporting and national security risk as a specific factor in evaluating markets. Its systems also monitor trading around the clock, freeze accounts when suspicious activity cannot be quickly resolved, and use third-party intelligence from IC360.
Polymarket’s newly disclosed referrals show it has its own monitoring capability, but Kalshi has been more public and granular about its controls. That difference could matter as regulators look beyond claims of federal jurisdiction and ask whether prediction market operators are actually equipped to police insider trading.
What comes next for Polymarket
CNN reported that the DOJ is investigating the referrals, but the status of specific accounts was not disclosed.
The DOJ has already shown that it is willing to prosecute alleged insider trading in prediction markets, undermining any argument that these platforms are a legal gray zone free from traditional fraud enforcement.
For Polymarket, the next challenge is proving that integrity monitoring is not a reactive public relations tool but a system capable of finding, freezing and escalating suspect activity before sensitive information is monetized or revealed through the market itself.
