Wisconsin Attorney General Josh Kaul has filed a lawsuit against Kalshi, Coinbase, Polymarket, Robinhood, and Crypto.com, accusing them of operating unlicensed gambling businesses. The lawsuit claims these platforms offer "event contracts" that are essentially wagers, violating state gambling laws. The platforms' marketing, such as Kalshi's "first legal sports betting platform" claim, is cited as evidence. The complaint highlights that the platforms' fee structures resemble casino operations, charging per transaction. The legal battle centers on whether these contracts fall under federal CFTC regulations or state gambling laws. Similar cases are pending in other states, with a resolution potentially reaching the U.S. Supreme Court.