Polymarket is facing manipulation allegations after a trader claimed the platform unfairly changed settlement rules to cancel a winning bet on whether Strategy had sold Bitcoin during a specified timeframe.

I was just scammed for $500K by Polymarket.

I am "willo2", the top holder of YES on "MicroStrategy sells Bitcoin by May 31st".

Here's what happened: pic.twitter.com/4n81IdvLXI

— willo2 (@willo2_Poly) June 2, 2026