Polymarket and Underdog sue Ohio regulator as five rivals comply

Polymarket and Underdog Predict filed separate lawsuits against the Ohio Casino Control Commission on the grounds that federal regulation of sports event contracts overrides state gambling law — a position that puts them in direct opposition to five of their competitors, who have already pulled out of Ohio without a legal fight.

The OCCC sent cease-and-desist letters to ten companies in total. Coinbase moved first. Robinhood, Gemini, Moomoo Financial, and Plus500US followed. That is half the named group, and the compliance came without public resistance. Novig, ProphetX, and Webull have not yet indicated which way they will go.

The legal argument Polymarket and Underdog are making is structurally familiar. It is the same preemption claim Kalshi ran in federal court, with enough early success to encourage others and enough subsequent setbacks to counsel caution. The Sixth Circuit ruled against Kalshi in Ohio in late September. That ruling did not resolve the underlying federal question permanently, but it told the OCCC something useful: at least one federal appellate panel found its enforcement position defensible. Polymarket and Underdog are filing into that environment, not into a vacuum.

The mechanism matters here. A CFTC-registered designated contract market has a credible argument that state gambling regulators cannot impose a parallel licensing requirement on contracts the CFTC has approved. But that argument has performed differently across circuits, and Ohio's Sixth Circuit precedent is now on the state's side. Polymarket's regulatory position is not identical to Kalshi's — Polymarket received NFA approval rather than full DCM status — and that distinction will matter in how the Ohio court evaluates federal preemption. Whether NFA approval carries the same preemptive weight as DCM registration is a question the existing case law has not fully answered.

What I read differently from the consensus here is the significance of the compliance split. The reporting frames five companies complying and two suing as a standard regulatory divergence. I think it is more structurally informative than that. The companies that complied — Coinbase, Robinhood, Gemini, Moomoo, Plus500US — are predominantly brokerage and exchange platforms for whom sports event contracts are a product line, not a core business. Polymarket and Underdog are prediction market platforms for whom Ohio is not incidental. The asymmetry in compliance behavior reflects the asymmetry in what losing Ohio actually costs each party. That is not a coincidence, and it predicts how hard each side will fight.

The hearing is not yet scheduled in Polymarket and Underdog's cases. Utah's federal challenge to the CFTC has first filings due November 10 and a hearing set for November 20, which means the broader federal-state collision will produce new legal facts within days. Whatever Utah's federal judge says about CFTC preemption authority will land while Ohio's cases are still in their early stages. The timing is not ideal for Polymarket and Underdog — they are filing lawsuits into a legal landscape that is actively shifting under their feet.