A Green Beret’s alleged $400,000 insider bet on a raid in Venezuela seemed like an isolated breach. A new report suggests it may be the visible edge of something broader.
The Anti-Corruption Data Collective (ACDC), a nonprofit research group, analyzed every settled Polymarket contract from January 2021 through mid-March 2026 — more than 435,000 markets and $54.4 billion in cumulative volume — and found that low-probability bets on military and defense outcomes win at rates that are difficult to explain through skill or luck.
Across political markets, such “longshot” bets typically succeed about 14% of the time. In military-linked contracts, success rates have topped 50% in some cases.
“Markets tied to specific government policies, such as military and defense and foreign affairs, are harder to forecast using public information alone,” the authors wrote, making them “more susceptible to information asymmetries,” including insider trading or specialized knowledge.
In those markets, the gap between informed and uninformed traders may be widest, creating conditions in which a small group can consistently outperform not just by reacting faster, but by knowing more.
For its part, Polymarket touts its market surveillance teams and cooperation with the Department of Justice on the Venezuela case. Trading on confidential knowledge is prohibited on the platform, as it is on Kalshi.
Concentrated profits
The ACDC report’s findings add to a growing body of research pointing in the same direction. A working paper from London Business School and Yale found that roughly 3% of traders account for most price discovery on Polymarket.
Separate analysis from blockchain analytics firm Solidus Labs showed that profits are even more concentrated, with fewer than 1% of wallets capturing about half of all gains. ACDC’s contribution is to suggest where some of that edge may come from.
The report examines the June 2025 U.S. strikes on Iran as a case study. Polymarket listed several date-specific contracts on whether a strike would occur. Markets tied to June 19 and June 20 expired without incident, and no longshot bets won.
The strike came at 18:40 ET on June 21. 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 that, a small number of traders placed large, well-timed bets on the outcome.
The pattern extends beyond 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 imply.
Longshot bets can outperform for other reasons, including mispricing or shifts in public expectations. But 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.
ACDC, being a nonprofit research group funded through the Fund for Constitutional Government, has no surveillance product to sell, compared to Solidus Labs, whose own recent Polymarket analysis doubles as a marketing case for the platform it licenses to Kalshi.
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’s conclusion goes further, calling for “an evidence-informed debate about whether the public should be betting on these outcomes at all.”
Source: https://www.coindesk.com/markets/2026/04/30/polymarket-s-military-markets-show-signs-of-insider-edge-report-suggests
