Crypto news: researchers from Stanford University and Singapore Management University found that Polymarket’s five-minute Bitcoin prediction contracts incentivized traders to manipulate spot prices, harming ordinary participants. The study said the contract design led to this issue, and recommended extending the contract duration from five minutes to fifteen minutes to reduce manipulation risk. The study also mentioned that traditional exchanges such as Nasdaq and CBOE are exploring similar contracts, highlighting the importance of settlement methods. Despite the design flaws, the prediction market still attracted record-breaking trading activity: in June, Kalshi’s trading volume was about $9.4 billion, while Polymarket’s was $4.3 billion.