A Massachusetts judge on Tuesday allowed state regulators to temporarily bar Kalshi from offering sports-related prediction markets in the state, saying regulators view the products as unlicensed sports betting rather than federally regulated event contracts. The order responds to the state’s effort to enforce its gambling laws against platforms that have grown large and popular.
Judge Christopher Barry-Smith wrote in his opinion. “Prior to March 2025, Kalshi referred to itself in advertisements as ‘the first nationwide legal sports betting platform,’”
The court issued a preliminary injunction that could require Kalshi to stop its sports markets as soon as Friday. (Ed. note: This is the first U.S. court order forcing a prediction market to halt services while litigation proceeds.)
The company and rivals have argued their offerings are event contracts overseen by the CFTC, not state gambling. State lawyers counter that the contracts function like digital gambling and thus fall under state authority.
Data shows sports-related wagers account for over 80% of Kalshi’s business, and the platform recorded roughly $26 billion in trading volume on those markets, according to Data shows. Legal expert Daniel Wallach highlighted the ruling’s importance and suggested a move against Polymarket was possible in a tweet.
Outside the U.S., regulators in Portugal and Hungary have also moved to ban Polymarket, accusing the site of facilitating illegal gambling activity.
