A Polymarket trader has accused the prediction market platform of unfairly resolving a disputed market tied to Strategy’s first Bitcoin sale in years. The trader claims he lost around $500,000 after betting that the firm had sold BTC before a May 31 deadline – something that was officially confirmed by an SEC filing on June 1. Strategy’s Bitcoin Sale Sparks Serious Controversy The whole thing centers on a Polymarket event asking whether MicroStrategy (later rebranded to Strategy) would sell any of its Bitcoin by a specific date. The rules stated that the market would resolve to “Yes” if the company sold any BTC by 11:59 ET on May 31. Resolution sources included on-chain data, disclosures, and credible reporting. On June 1, Strategy filed an 8-K with the Securities and Exchange Commission. As CryptoPotato reported , the firm sold 32 BTC worth approximately $2.5 million between May 26 and May 31 – clearly within Polymarket’s resolution period. However, the filing came one day after the May 31 market deadline, creating the central dispute: should the event be judged by when the sale occurred, or by when it was publicly confirmed? Trader Says Polymarket Added a Rule After the Fact According to the trader, he started buying “Yes” shares after noticing that Strategy had deposited around $30 million of BTC into Coinbase Prime a week ago – a move that escalated speculations that the firm would sell. He said he had reviewed on-chain data, checked past wallet activity, and concluded that Strategy had likely sold BTC before the deadline. After the firm confirmed the sale on June 1st through the SEC filing, the trader increased his position. He said that the market was still open, arguing that the rules only required a sale within the timeframe – not confirmation within the timeframe. Here’s where it gets interesting. The trader claims that Polymarket added a clarification stating that confirmation achieved outside the market’s timeframe would not qualify. And they did that after the fact. Later, Polymarket added clarification. “No information from MSTR, on-chain data, or consensus of credible reporting confirmed that MicroStrategy sold Bitcoin within the market’s timeframe. Confirmation achieved outside of the market’s time frame does not qualify.” pic.twitter.com/60O3S1q4LV — willo2 (@willo2_Poly) June 2, 2026 The user said that the move constituted a new rule and alleged that the market should either have resolved to “Yes” or closed on May 31 if post-deadline confirmation was not allowed. At the time of this writing, the market has been resolved to “No.” The main problem here, according to other traders on Polymarket, is that anyone can dispute a market’s resolution by posting a bond, which triggers a debate period. During that debate period, a set of people who hold UMA tokens vote on the correct resolution according to the predefined rules. Many argue that this creates a situation in which UMA whales can manipulate markets during dispute windows, and that Polymarket is doing nothing about it. The post Trader Claims Polymarket Scammed Him for $500K on MicroStrategy’s Bitcoin Sale Market appeared first on CryptoPotato .
