The alleged $400,000 insider bet by a Green Beret on a raid in Venezuela may be just the tip of the iceberg. A new report by the Anti-Corruption Data Collective, a nonprofit research group, has analyzed over 435,000 markets and $54.4 billion in cumulative volume on Polymarket from January 2021 to mid-March 2026. The findings suggest that low-probability bets on military and defense outcomes have success rates that defy explanation by skill or luck alone, with some cases seeing success rates of over 50%. This is in stark contrast to the typical 14% success rate for such 'longshot' bets across political markets.

The report's authors attribute this anomaly to the difficulty of forecasting these markets using public information, making them more susceptible to insider trading or specialized knowledge. The study also notes that a small group of traders can consistently outperform others due to their access to confidential information. The report's findings are consistent with previous research, which has shown that a small percentage 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 across contracts that ultimately resolved YES, with eight wallets sharing about $1.8 million in profits. The pattern of well-timed bets on military and defense outcomes extends beyond this single event, with the report finding that winning longshot bets outnumbered losing ones in five of the six two-hour windows before market resolution.

While longshot bets can outperform due to various reasons, 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 contract granularity.

Ultimately, the report calls for an evidence-informed debate on whether the public should be betting on these outcomes at all.