A federal judge in Minnesota issued a preliminary injunction to stop a new state law banning most prediction markets, just days before it was to take effect. The law, passed in May, would have made it a felony for prediction markets to operate or advertise in Minnesota. The big picture: The Commodity Futures Trading Commission (CFTC) and two prediction market platforms, Kalshi and Polymarket, had sued, arguing that only the federal government can regulate these platforms. Concerns have grown that prediction markets are being manipulated by insiders or fostering gambling addictions, leading multiple states to attempt bans or restrictions. The CFTC has challenged many state-level restrictions, claiming federal law overrides state attempts to ban prediction markets.