BOSTON — A Massachusetts judge ruled Tuesday that prediction-markets operator Kalshi cannot let state residents bet on sports through its online platform, after the state’s attorney general accused it of running afoul of gaming regulators.
Suffolk County Superior Court Judge Christopher Barry-Smith in Boston said he will issue a preliminary injunction at the request of Massachusetts Attorney General Andrea Joy Campbell that would prohibit Kalshi from allowing users in the state to use its platform to place financial bets on the outcomes of sporting events without a license.
“There is no real question that licensure, and the consequent oversight, of sports wagering operations in the state serves both public health and safety, and the Commonwealth’s financial interest,” Barry-Smith wrote.
The judge said he plans to finalize an injunction requiring the company to comply with the state’s sports wagering law going forward following a hearing on Friday, where he will also consider whether to pause his order to allow time for an appeal.
Campbell in a statement called the ruling “a major step toward fortifying Massachusetts’ gambling laws and mitigating the significant public health consequences that come with unregulated gambling.”
Kalshi declined to comment but has previously indicated it would appeal any injunction.
The New York-based company gives its users the opportunity to profit from predictions on events ranging from sports and entertainment to politics and the economy.
It began offering sports events contracts nationally in January 2025, and they have quickly become a majority of Kalshi’s trading volume, according to the judge’s ruling.
While Kalshi is engaged in litigation with several other states that have accused it of flouting their gaming laws by offering users the ability to bet on the outcomes of sporting events like football and basketball, Massachusetts was the first to seek an injunction to halt its operations.
Campbell, a Democrat, in a lawsuit filed in September said that Kalshi was offering sports wagering under the guise of event contracts without seeking a license from the Massachusetts Gaming Commission.
Her office argued that while licensed gaming operators in the state are barred from offering sports wagering to anyone under 21, Kalshi was offering an addictive betting product without a license to consumers as young as 18 in high school.
Kalshi argued that state gaming laws like Massachusetts’ do not apply to its sports events contracts, which Kalshi contends the U.S. Commodity Futures Trading Commission has exclusive jurisdiction over given its authority over exchange-traded “swaps,” a type of derivative contract.
Kalshi pointed to its status as a registered contract market with the CFTC.
But Barry-Smith said Kalshi took an “overly broad” view of federal law, saying Congress never intended to displace traditional state powers to regulate gambling, which can exist in “harmony” with the CFTC’s regulatory authority.
To support his ruling, he cited Kalshi’s loss in a related case in November, when a federal judge in Nevada, a leader in gambling regulation, similarly found that the company was subject to that state’s gaming rules.