The state's casino regulator sent cease-and-desist letters to Polymarket, Coinbase, Robinhood and seven others. Kalshi, already in separate litigation, was left off.
Prediction Markets · FinancialMarkets.com · October 6, 2026 · Tickers: HOOD, COIN, DKNG
Ohio has joined the states trying to shut down sports-related prediction markets, and its list reaches into mainstream brokerage apps.
The Ohio Casino Control Commission sent cease-and-desist letters dated Oct. 2 to 10 platforms: Polymarket, Coinbase, Robinhood, Gemini Titan, Underdog, Webull, Moomoo, Plus500, ProphetX and Novig. The platforms have until Oct. 16 to comply. "Sports gaming cannot be offered in Ohio without a license issued by the Commission," the letters state.
Who was left off
Kalshi is not on the list. It is already in separate litigation over its sports contracts.
The other names show how far event contracts have spread. Robinhood, Coinbase and Webull are retail brokerages that added prediction markets to apps used mainly for stocks and crypto. A cease-and-desist aimed at them affects a product line, not their core business, but it also puts licensed financial firms in direct conflict with a state gaming regulator.
A widening state campaign
Ohio follows Missouri, whose attorney general has sent similar letters to six operators. Litigation in Illinois continues, with a proposed injunction due Oct. 29. The U.S. Supreme Court's first orders list of the term did not take up any prediction-market case, leaving the conflict between federal commodity regulation and state gambling law unresolved for now.
The industry has been spending to defend its position. Kalshi, Polymarket and their trade group have put at least $3 million into lobbying and campaign contributions this year.
Activity on the platforms
Trading has kept growing at Kalshi. Contract volume on Kalshi rose about 17.3% last week, while volume on Polymarket's U.S. platform fell about 4.4%.
Two ways the deadline could go
One possibility is that the platforms block Ohio users from sports contracts by Oct. 16, keeping the fight narrow.
Another is that some challenge the letters, arguing that contracts listed on federally regulated exchanges fall under the Commodity Futures Trading Commission rather than state gaming law, which would add Ohio to the litigation map.
Oct. 16
Each platform's response by the deadline will show whether operators treat state orders as binding. A court challenge from any of the 10 would show whether the industry is ready to take the federal-preemption argument beyond Kalshi.