Polymarket and Robinhood sue Missouri over sports-event contracts

Polymarket US and Robinhood have filed separate federal lawsuits against Missouri officials to block the state from preventing them offering contracts on sporting events, according to complaints filed after cease‑and‑desist letters issued in September 2026. Polymarket US alleges Commerce Clause violations and seeks preliminary and permanent injunctions; Robinhood argues the contracts are financial products under the Commodity Futures Trading Commission’s jurisdiction.

Context and recipients of the letters

The suits follow cease‑and‑desist letters issued in September 2026 by Missouri Attorney General Catherine Hanaway, which threatened enforcement action against several prediction‑market operators. Those letters targeted Novig, Polymarket US, Robinhood, Kalshi, Underdog and Crypto.com and demanded they stop offering sports‑related contracts in the state.

Hanaway said the contracts constitute unauthorized sports betting in Missouri under the state’s sports‑betting framework launched in December 2025.

Polymarket US’s arguments

Polymarket US says Missouri’s regulatory and licensing requirements for sports‑betting operators violate the Commerce Clause of the United States Constitution by imposing restrictions on interstate commerce. The complaint specifically challenges a Missouri Gaming Commission rule that requires licensed operators to keep their servers physically located within Missouri.

Polymarket US’s filing also cites the Commodity Futures Trading Commission’s fair access interpretation of November 5, which the company says deems geographically restrictive measures incompatible with exchange rules when those measures were introduced to comply with state gaming laws. Polymarket US asks the court to declare Missouri laws unconstitutional as applied and preempted by federal law, and to grant preliminary and permanent injunctions to prevent enforcement.

Robinhood’s argument and quoted filing

Robinhood focuses its complaint on the CFTC’s authority over prediction markets. The company says contracts on sporting events are federally authorised financial products and therefore fall under the Commodity Futures Trading Commission’s jurisdiction, not state gaming laws.

"Missouri’s position rests on the premise that, despite express federal preemption and the CFTC’s comprehensive regulation of derivatives trading, event contracts listed on CFTC‑regulated DCMs and facilitated by CFTC‑registered FCMs constitute ‘wagering’ subject to Missouri gaming laws. Federal courts have long recognised that the CFTC’s regulation of the national derivatives market is exclusive and preempts state involvement," wrote Robinhood’s attorney in the complaint.

Robinhood asks the federal court to confirm federal regulatory supremacy over these contracts and to block any state action based on the attorney general’s letters.

Missouri requirements challenged

Under Missouri’s current system, authorised online sportsbooks must geographically restrict their operations to the state and maintain data centres and corporate infrastructure on its territory, creating a state‑by‑state operational model. Both companies challenge that regulatory architecture and seek court rulings to prevent its application to their operations.

Immediate implications

The lawsuits request injunctions while the legal merits are resolved in federal court. The proceedings set up a direct clash between the state regulatory regime enacted after December 2025 and the federal interpretation of derivative and event‑contract markets, including the CFTC guidance of November 5 cited by Polymarket US. The outcome will affect whether Missouri can enforce its server‑location and geographic‑restriction rules against these operators.

Regulation at stake and the boundary between state laws and federal jurisdiction will remain the focus during upcoming proceedings, which will determine whether Missouri may apply its requirements to these operators.