Half of 'long-shot' Polymarket bets on military action are successful, study finds
Source · Prediction Markets desk
— Summary
More than half of "long-shot" bets on military action made on Polymarket are successful, according to a new report by the Anti-Corruption Data Collective (ACDC) — a finding that suggests prediction markets pose a bigger insider-trading threat to sensitive information than previously recognised. ACDC analysed more than **400,000 markets** settled on Polymarket between January 2021 and March 2026 and found that long-shot bets — defined as wagers of $2,500 or more at odds of 35% or less — on military and defence markets had an average win rate of around **52%**. That compares with **25%** across politics-focused markets and just **14%** for all markets on the platform.
The report follows the first US prosecution of insider trading on prediction markets. Last week, prosecutors charged Gannon Ken Van Dyke, an active-duty soldier involved in planning the January raid to seize Venezuelan leader Nicolás Maduro, with placing **roughly 13 bets** worth **$33,034** on positions including "US Forces in Venezuela" and "Maduro out". The bets netted more than **$400,000**. Van Dyke pleaded not guilty Tuesday. Earlier this year Israel filed similar charges against a reservist and a civilian. ACDC says markets where outcomes are determined by small decision-making groups — particularly military and defence markets — are "structurally vulnerable to insider trading".
Activity on the platform remains heavy. Markets on whether the US and Iran will reach a permanent peace deal have seen **$63mn** in trading volume, while one on China invading Taiwan in 2026 has attracted **$23mn**. But sports still dominate: trading volume on this year's Super Bowl winner exceeded **$700mn**. Polymarket said Van Dyke's arrest was "proof the system works", noting it referred the matter to the US DoJ. A wave of start-ups now sells tools to copy suspected insider wallets — Unusual Whales charges $20/month, Polywhaler $4.99/month. A separate LSE study finds **just 3% of accounts** generate the bulk of price discovery on the platform. Source: Financial Times, 30 April 2026, Stephanie Stacey, Chris Cook and Jill R Shah.
The story in one line
Anti-Corruption Data Collective study finds 52% of long-shot ($2,500+ at ≤35% odds) Polymarket bets on military action win — vs 25% in politics and 14% market-wide — pointing to systemic insider trading on a platform where one US soldier already faces charges.
Top “geopolitics” markets on Polymarket
Most active Polymarket geopolitics markets (volume, $mn, as of 29 April 2026)
Market
Total volume ($mn)
Netanyahu out by …?
119
Venezuela leader end of 2026?
86
US x Iran permanent peace deal by …?
63
Will the Iranian regime fall by April 30?
48
Trump announces end of military operations against Iran by …?
39
Kharg Island no longer under Iranian control by …?
37
Will the Iranian regime fall by June 30?
35
Strait of Hormuz traffic returns to normal by end of April?
33
US x Iran diplomatic meeting by …?
27
Will China invade Taiwan by end of 2026?
23
Source: Financial Times, 30 April 2026, citing Polymarket data
Why it matters
Two findings are striking. First, the 52% vs 14% gap in win rates is statistically very large and points to information leakage from inside government and military decision-making — what ACDC calls “structural vulnerability”. Second, the financial scale: $63mn on a US-Iran peace bet, $23mn on a Taiwan-invasion bet, $700mn on the Super Bowl 2026. Volumes large enough that the platform itself is a market participant decision-makers in Washington, Tehran and Beijing must assume is reading their cards.
The regulatory consequences are coming. Democratic lawmakers Yassamin Ansari and Ritchie Torres have already framed military-action wagers as “a disturbing national security risk” and a “perverse incentive”. The contrast with rival Kalshi — which bans “violent markets, including war and kidnapping” — is the structural fault line. Polymarket’s pitch is openness; Kalshi’s is regulation. Watch which model wins as US and EU regulators look at this report.
Takeaway
For Delfineo readers tracking the geopolitical risk premium, Polymarket’s military-action markets are now too large to ignore — and too compromised to read as pure crowdsourced signal. The LSE finding that 3% of accounts drive most price discovery should be the framework: trust the platform when the informed minority is broad and incentives are clean, and discount the signal where insider information is endemic.
Source: Financial Times, 30 April 2026, Stephanie Stacey, Chris Cook and Jill R Shah.