The alleged insider bet of $400,000 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) indicates 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, with a cumulative volume of $54.4 billion, and discovered that low-probability bets on military and defense outcomes have success rates that are difficult to explain by skill or luck alone. Typically, such 'longshot' bets succeed around 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 specific government policies, including military and defense and foreign affairs, are particularly challenging to forecast using only public information, making them more vulnerable to information asymmetries, such as insider trading or specialized knowledge. This creates an environment where a small group of traders can consistently outperform others, not just by reacting faster, but by having access to more information. Polymarket emphasizes its market surveillance teams and cooperation with the Department of Justice on the Venezuela case, and it prohibits trading on confidential knowledge on its platform, as does Kalshi.
The ACDC report's findings contribute to a growing body of research pointing in the same direction. A working paper from 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 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. The strike happened 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 YES. Eight wallets shared about $1.8 million in profits, with one taking nearly $500,000. The Pentagon had designed the operation to be unreadable from the outside, using decoy bombers and long-range stealth aircraft to avoid detection.
Despite this, a small number of traders placed large, well-timed bets on the outcome. The pattern extends beyond a single event, as the report found 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, contrary to what market prices imply.
While longshot bets can outperform for other reasons, such as mispricing or shifts in public expectations, the consistency of the patterns, especially in markets tied to military decisions, suggests that some participants may be operating with information advantages that others do not have. The ACDC, being a nonprofit research group, has no surveillance product to sell, unlike Solidus Labs, whose recent Polymarket analysis doubles as a marketing case for the platform it licenses to Kalshi. The ACDC's recommendations include 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.'