Polymarket is facing accusations of market manipulation and rule-changing after resolving a high-volume prediction market bet on MicroStrategy's Bitcoin holdings in a manner that community members say contradicted pre-agreed conditions. The disputed market, which attracted approximately $118 million in trading volume, centered on whether MicroStrategy would sell any Bitcoin by May 31, 2026, and was ultimately resolved as "No"—but not before sparking significant controversy.
According to users who challenged the resolution, MicroStrategy had already sold Bitcoin prior to May 31, 2025, yet Polymarket's team declined to clarify the resolution criteria before the market closed and only retroactively adjusted its interpretation of the rules after trading concluded. Critics estimate the disputed resolution cost participants hundreds of thousands of dollars in losses while Polymarket earned over $100,000 in commissions from the bet.
The conflict highlights a critical vulnerability in decentralized prediction markets: the reliance on platform discretion in interpreting ambiguous outcome definitions. Despite the resolution standing as finalized, Polymarket users continue to demand a formal review of the decision, raising questions about transparency and fairness in the platform's dispute resolution process for high-stakes markets.