An alleged $400,000 insider bet by a Green Beret on a Venezuela raid initially seemed like an isolated incident. However, a new report by the Anti-Corruption Data Collective (ACDC) suggests it may be just the tip of the iceberg.
The nonprofit research group analyzed over 435,000 Polymarket contracts from January 2021 to mid-March 2026, totaling $54.4 billion in volume, and found that low-probability bets on military and defense outcomes have success rates that are difficult to explain by skill or luck alone, sometimes exceeding 50%. Typically, such 'longshot' bets succeed around 14% of the time across political markets.
The authors note that markets tied to government policies, such as military and defense, are harder to forecast using public information, making them more susceptible to insider trading or specialized knowledge. This creates conditions where a small group can consistently outperform others, not just by reacting faster, but by having more information. Polymarket emphasizes its market surveillance and cooperation with the Department of Justice, especially in the Venezuela case, where trading on confidential knowledge is prohibited.
The ACDC report adds to existing research indicating that roughly 3% of traders account for most price discovery on Polymarket, with 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. Despite the operation being designed to avoid detection, a small number of traders placed large, well-timed bets on the outcome.
The pattern extends beyond this single event, with winning longshot bets outnumbering losing ones in five of the six two-hour windows before market resolution in Polymarket's military and defense category. While longshot bets can outperform due to mispricing or shifts in public expectations, the consistency of these patterns, especially in markets tied to military decisions, suggests some participants may have information advantages. The ACDC recommends identity verification for bettors, conditional payouts on suspicious wagers, restrictions on markets decided by small groups, and limits on contract granularity. The report concludes by calling for an informed debate on whether the public should be betting on these outcomes at all.