The alleged $400,000 insider bet by a Green Beret on a Venezuela raid initially seemed like an isolated incident, but new findings suggest it may be just the tip of the iceberg. The Anti-Corruption Data Collective, a nonprofit research organization, analyzed over 435,000 Polymarket contracts and $54.4 billion in cumulative volume from January 2021 to mid-March 2026. The results show that low-probability bets on military and defense outcomes have success rates that are difficult to explain by skill or luck alone, with some cases reaching 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 note that markets related to government policies, such as military and defense, are particularly challenging to forecast using public information, making them more susceptible to information asymmetries, including insider trading. The gap between informed and uninformed traders may be widest in these markets, creating an environment where a small group can consistently outperform others. The report's findings add to a growing body of research indicating that a small percentage of traders account for most price discovery on Polymarket, with roughly 3% of traders driving prices and fewer than 1% of wallets capturing about half of all gains. The report examines the June 2025 U.S.
strikes on Iran as a case study, where 19 longshot bets totaling $164,292 were placed in the hours leading up to the strike, with eight wallets sharing about $1.8 million in profits. The pattern of winning longshot bets extends beyond this single event, with the report finding that in five of the six two-hour windows before market resolution, winning longshot bets outnumbered losing ones in Polymarket's military and defense category. While longshot bets can outperform due to various reasons, including mispricing or shifts in public expectations, the consistency of the patterns suggests that some participants may be operating with information advantages. The report recommends identity verification for bettors, conditional payouts on suspicious wagers, restrictions on markets whose outcomes are decided by small groups, and limits on how granular contracts can become.
Ultimately, the report concludes that there should be an evidence-informed debate about whether the public should be betting on these outcomes at all.