JeffHK sells much of US-Cuba war bet at five-figure loss
Updated
Updated · USA TODAY · May 7
JeffHK sells much of US-Cuba war bet at five-figure loss
6 articles · Updated · USA TODAY · May 7
The Polymarket trader had staked $57,500 on a 2026 US invasion of Cuba and was down about $34,000 on paper before selling early on 7 May.
Analysts said the oversized trade, made from a new account with no other positions, showed suspicious signs of either insider belief or unsophisticated, high-conviction betting.
He remains the market’s biggest investor and could still profit if an invasion occurs, as scrutiny of prediction-market insider trading grows after a US soldier was charged in a separate case.
Are prediction markets the next frontier for foreign espionage and disinformation campaigns?
As platforms move offshore, can U.S. regulators win the fight against insider trading?
The $57,500 JeffHK Bet That Distorted Polymarket’s Cuba Invasion Odds by 50 Points
Overview
In early May 2026, a new Polymarket user named JeffHK placed a massive $57,500 bet predicting a U.S. invasion of Cuba, causing the market's 'Yes' probability to surge from 15% to 65% due to low liquidity. This large, concentrated bet and JeffHK's partial sell-off at a $34,000 loss raised red flags and sparked accusations of market manipulation. Polymarket responded with transparency and cooperation with authorities. The incident intensified concerns about insider trading and manipulation, accelerating regulatory actions like the U.S. Senate's ban on lawmakers betting on prediction markets. Meanwhile, historical context and lack of invasion preparations make the predicted event highly improbable, highlighting prediction markets' vulnerability to distortion in complex geopolitical bets.