Wisconsin Attorney General Josh Kaul filed a lawsuit in Dan County on April 23 against Kalshi, Robinhood, Coinbase, Polymarket, and Crypto.com, accusing these fintech and crypto platforms of facilitating illegal sports betting through event contracts. Kaul is seeking preliminary and permanent injunctions to declare the platforms' operations illegal under Wisconsin betting law and a public hazard. The complaint states that rebranding betting as event contracts does not change their fundamental function; Kalshi derives approximately 90% of its business from sports-related contracts, generating over $1 billion in annualized revenue. Robinhood and Coinbase are also implicated in the case because they route user orders to the Kalshi marketplace through distribution agreements. Regulatory agencies in Nevada, Arizona, and Tennessee have also taken similar legal action or issued stop-loss orders.