Stanford study finds Polymarket BTC bets may be linked to Binance price manipulation

Stanford University researchers have published a study suggesting that some traders in Polymarket's main BTC prediction market may have temporarily moved BTC prices to influence betting outcomes. According to Bloomberg, the researchers identified a pattern on Binance where concentrated, one-directional trades in the final seconds before a bet expired caused temporary price fluctuations, benefiting traders who had bet on that direction. This phenomenon was most pronounced when a slight price change could determine the outcome of a bet. The researchers concluded that this was an attempt to manipulate results by temporarily pushing the spot price. They noted that while Polymarket's five-minute BTC price bets are settled based on data from multiple oracles, approximately 85% of contract outcomes during the study period moved in the same direction as Binance's price, implying it was used as a proxy for the final settlement price. Although the traders' intent was not directly observed, the researchers inferred the possibility of price manipulation by analyzing trading patterns. The study pointed out that unlike prediction markets for elections or sports, those based on financial assets carry a structural risk of manipulation because participants can directly trade the underlying asset that determines the outcome.