The alleged insider bet of $400,000 by a Green Beret on a Venezuelan raid initially seemed like an isolated incident. However, a new report by the Anti-Corruption Data Collective (ACDC) implies it might be just the tip of the iceberg. The nonprofit research group analyzed over 435,000 settled Polymarket contracts from January 2021 to mid-March 2026, totaling $54.4 billion in volume, and discovered that low-probability bets on military and defense outcomes have success rates that defy explanation by skill or luck alone. Typically, such 'longshot' bets succeed about 14% of the time across political markets, but in military-linked contracts, success rates have reached as high as 50% in some cases.
The authors of the report noted that markets related to government policies, such as military and defense and foreign affairs, are particularly challenging to forecast using only public information, making them more vulnerable to information asymmetries, including insider trading or specialized knowledge. This creates an environment where a small group of traders can consistently outperform others, not just by reacting more quickly, but by possessing more knowledge.
Polymarket has emphasized its market surveillance teams and collaboration with the Department of Justice on the Venezuela case, highlighting that trading on confidential knowledge is prohibited on the platform, a policy also upheld by Kalshi. The report's findings contribute to a growing body of research pointing in the same direction. A working paper from the London Business School and Yale found that approximately 3% of traders are responsible for most price discovery on Polymarket. Separate analysis by blockchain analytics firm Solidus Labs showed that profits are even more concentrated, with less than 1% of wallets capturing about half of all gains.
The ACDC report suggests that some of this edge may stem from insider knowledge. The report examines the June 2025 U.S. strikes on Iran as a case study, where Polymarket listed several date-specific contracts on whether a strike would occur.
Markets tied to June 19 and June 20 expired without incident, with no longshot bets winning. The strike occurred at 18:40 ET on June 21, and in the hours leading up to it, 19 longshot bets totaling $164,292 were placed across the contracts that ultimately resolved to YES. Eight wallets shared about $1.8 million in profits, with one wallet taking nearly $500,000. The operation was designed by the Pentagon to be undetectable from the outside, using decoy bombers and long-range stealth aircraft to avoid detection.
Despite these efforts, a small number of traders placed large, well-timed bets on the outcome. This pattern is not isolated to a single event; across Polymarket's military and defense category, the report found that in five of the six two-hour windows before market resolution, winning longshot bets outnumbered losing ones, contrary to what market prices would imply. While longshot bets can outperform due to other factors such as mispricing or shifts in public expectations, the consistency of these patterns, especially in markets tied to military decisions, suggests that some participants may be operating with information advantages not available to others. ACDC, as a nonprofit research group funded through the Fund for Constitutional Government, does not have a surveillance product to sell, unlike Solidus Labs, whose recent Polymarket analysis also serves as a marketing case for the platform it licenses to Kalshi.
The report's recommendations include implementing 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. The report concludes by calling for 'an evidence-informed debate about whether the public should be betting on these outcomes at all.'