Prediction markets Polymarket and Kalshi face stolen debit card scams
Prediction markets like Polymarket and Kalshi have become a hot spot for scams, with criminals using stolen debit cards to place bets and, if they won, withdraw the funds.
The issue surfaced in February 2026 when Polymarket's payment processor noticed a flood of suspicious transactions, revealing that at least $10 million had been targeted through Polymarket.
Polymarket processor rejected over 80% transactions
Polymarket's payment processor ended up rejecting more than 80% of transactions as fraudulent, well above the usual 1% in most industries.
Despite this, CEO Shayne Coplan told his horrified compliance team to keep things running, holding off on tackling the fraud.
Experts like former attorney for the Commodity Future Trading Commission Joe Konizeski point out that such problems are rare in regulated spaces, highlighting how little oversight these prediction markets actually have.