Wisconsin Files Lawsuits Against Prediction Market Platforms Over Sports Contracts

Wisconsin’s Department of Justice filed lawsuits on 24 April 2026 against Kalshi, Polymarket, Robinhood, and Coinbase, targeting predictive market platforms that offer contracts on sports outcomes. The state argues that these products constitute unlicensed gambling under Wisconsin law.

The lawsuits, filed in Dane County and signed by Attorney General Josh Kaul, claim the platforms have been accepting wagers from Wisconsin residents without holding a state gambling license. Each platform is named in separate but related complaints, reflecting what the state describes as a coordinated ecosystem enabling unregulated sports betting.

The Legal Argument: Bets or Financial Instruments?

At the center of the case is a key question: are sports event prediction contracts legitimate financial products, or are they simply bets under another name?

Kalshi has consistently argued that its contracts are regulated financial instruments - specifically swaps - falling under the jurisdiction of the Commodity Futures Trading Commission (CFTC). Under this view, federal oversight would preempt state gambling laws.

Wisconsin’s DOJ rejects that argument. The complaints point to how these platforms present themselves publicly, including marketing language that refers to “betting” on event outcomes. According to state prosecutors, the structure of these contracts “falls squarely within” Wisconsin’s legal definition of a bet, regardless of how the transactions are labeled or processed.

The filings also claim that a significant portion of Kalshi’s activity is tied to sports-related contracts, reinforcing the state’s position that the platform is effectively operating as a sportsbook without a license.

How Wisconsin Structured the Cases

Rather than filing a single lawsuit, Wisconsin split its legal action into multiple cases targeting different parts of the ecosystem.

One complaint focuses on Polymarket and its affiliated entities. Another targets Kalshi directly, as well as distribution partners such as Robinhood and Coinbase. In that filing, the state argues that these platforms actively route orders to Kalshi, thereby making them jointly responsible for facilitating unlicensed betting activity.

This multi-pronged approach suggests the state is not only targeting the core platform operators but also the broader infrastructure that enables access to these markets.

US Regulators Taking a Closer Look at Prediction Markets

Wisconsin’s move is part of a broader national debate over how prediction markets should be regulated. Courts are already reviewing similar cases at the appellate level, and the divide between federal financial oversight and state gambling law remains unresolved.

Other states are beginning to follow suit. Pennsylvania regulators have warned against prediction markets developing outside the state’s legal and tax framework, creating risks for both consumers and licensed operators.

The outcome of these lawsuits could help determine whether platforms like Kalshi and Polymarket fall under the exclusive authority of the CFTC or whether states retain the right to regulate them as gambling operators.

What This Means for Users of Prediction Platforms

For users in Wisconsin, the immediate impact will depend on how the courts respond. If the state prevails, platforms named in the lawsuits could be forced to stop accepting users from Wisconsin or face financial penalties.

For users in other states, nothing changes in the short term. However, the outcome of this case could influence how regulators nationwide approach prediction markets, potentially leading to broader restrictions or clearer rules around their operation.

Importantly, the case does not affect US-licensed sportsbooks and casinos operating within regulated frameworks. These operators continue to offer services under state-approved licenses, with established rules around deposits, withdrawals, and consumer protections.

A Defining Test for Prediction Markets

This legal challenge goes beyond a single state dispute. It raises fundamental questions about where financial trading ends and gambling begins - and who has the authority to draw that line.

As the case moves through the courts, it could reshape how prediction markets operate across the United States. A ruling in favor of Wisconsin would strengthen state control over these platforms, while a decision backing federal jurisdiction could allow them to continue expanding under existing financial regulations.

Either way, the outcome is likely to set a precedent that defines the future of prediction markets in the US.