The alleged insider trading incident involving a Green Beret, who reportedly made a $400,000 bet on a raid in Venezuela, may be just the tip of the iceberg. A new report by the Anti-Corruption Data Collective (ACDC) analyzed over 435,000 Polymarket contracts and $54.4 billion in trading volume from January 2021 to mid-March 2026, revealing that low-probability bets on military and defense outcomes have success rates that cannot be easily explained by skill or luck, with some cases seeing success rates of over 50%.
This is significantly higher than the typical 14% success rate for longshot bets in political markets. The authors of the report suggest that markets related to government policies, such as military and defense, are more susceptible to information asymmetries, including insider trading, due to the difficulty in forecasting outcomes using public information alone.
This creates an environment where a small group of informed traders can consistently outperform others. The report's findings are consistent with existing research, which shows that a small percentage of traders, approximately 3%, account for most price discovery on Polymarket, and that profits are highly concentrated, with less than 1% of wallets capturing around half of all gains. The ACDC report examines the June 2025 U.S. strikes on Iran as a case study, finding that in the hours leading up to the strike, 19 longshot bets totaling $164,292 were placed across contracts that ultimately resolved in favor of the strike, with eight wallets sharing approximately $1.8 million in profits.
The report's authors suggest that some participants may be operating with information advantages that others do not have, and recommend measures such as identity verification for bettors, conditional payouts on suspicious wagers, and restrictions on markets whose outcomes are decided by small groups. The report concludes by calling for an evidence-informed debate on whether the public should be allowed to bet on these outcomes at all.