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Massachusetts has become a focal point in the legal battle over sports prediction markets.
A Suffolk County Superior Court judge has granted a preliminary injunction barring Kalshi from offering sports-related contracts to state residents until it obtains a Massachusetts sports wagering license. The ruling raises the stakes for how these platforms operate nationally and represents the strongest state action against such markets to date.
Judge moves fast to block Kalshi in Massachusetts
The decision establishes a clear path forward but does not nullify existing contracts. The court allowed either party to request a hearing and set a brief timeline for enforcing the injunction. Kalshi may also appeal to the Appeals Court and request a stay, which the company has indicated it may do.
State representatives argued that Kalshi’s product functions like sports betting under Massachusetts law while avoiding the state’s licensing process. The judge agreed that blocking new sports contracts while the lawsuit is pending was justified, finding that the Commonwealth is likely to prevail.
Kalshi’s federal preemption argument rejected
Kalshi’s defense relied heavily on federal oversight, claiming its event contracts fall under the Commodity Futures Trading Commission’s exclusive jurisdiction, leaving Massachusetts without authority to intervene.
The court rejected that argument, noting no clear signal from Congress indicates that state gambling laws should be overridden. Federal regulation of derivatives and state regulation of gambling, the judge wrote, can coexist. Requiring a state sports wagering license does not interfere with federal oversight but instead imposes rules to protect consumers.
Massachusetts cites Nevada loss in Kalshi case
Massachusetts was not the first jurisdiction to address Kalshi’s claims. The judge cited a recent federal case in Nevada, where Kalshi raised similar arguments and lost. That court concluded that Congress would have been explicit if it intended to dramatically change gambling regulation in the U.S.
The Massachusetts ruling echoed that reasoning, warning that sweeping changes to state gambling authority do not happen quietly or by accident.
Public safety and market integrity drive injunction
The judge also considered whether the injunction served the public interest. Massachusetts Attorney General Andrea Campbell brought the case, and the court concluded it did. State laws governing sports betting are designed to prevent underage wagering, address problem gambling, and ensure operators meet uniform standards. Licensed sportsbooks adhere to strict regulations and pay taxes and fees supporting these safeguards.
Allowing an unlicensed platform to operate outside this framework, the ruling noted, weakens consumer protections and creates an unfair competitive advantage.
Sports features put Kalshi under legal spotlight
The court examined how Kalshi presents its sports contracts, noting the use of familiar betting terms such as point spreads, over/unders, propositions, and parlays. It also highlighted design elements—leaderboards, countdown clocks, and continuous engagement features—that mirror traditional online sportsbooks.
Those similarities became more pronounced as sports predictions have grown central to Kalshi’s business. The court noted that sports-related contracts now account for roughly 90% of the platform’s trading volume, sometimes exceeding activity on licensed sportsbooks like DraftKings and FanDuel during comparable periods.
