Massachusetts Files Amended Suit Against Kalshi Over Sports Betting

Massachusetts Attorney General Andrea Joy Campbell has filed an amended complaint against prediction-market platform Kalshi, extending the state's legal challenge over its sports betting business.

Cointelegraph reported on July 30 that Suffolk County Superior Court Judge Peter Krupp allowed the state to file the 71-page amended complaint. The revised filing adds allegations involving minors to the state's existing claim that Kalshi operated a sports betting service in violation of Massachusetts law.

In the amended complaint, the state alleged that Kalshi “targeted users under 21 and took few meaningful steps to prevent them from using the platform.” It also pointed to marketing aimed at college campuses and advertisements featuring people who appeared to be under 21. The state said Kalshi allows anyone 18 or older to open an account and bet on sporting events through event contracts.

Campbell sued Kalshi in September 2025, arguing the company must obtain approval from the Massachusetts Gaming Commission to comply with the state's online sports betting rules. In January, the court issued a preliminary injunction barring Kalshi's sports event contract service while the case is under review.

Kalshi's sports betting service has been blocked in some states, even as it has won support at the federal level from the Commodity Futures Trading Commission. In a brief filed with a Massachusetts court in April, the CFTC asserted “exclusive jurisdiction” over prediction markets. CFTC Commissioner Summer Mersinger said Congress gave the agency sole authority to regulate commodity derivatives markets, including prediction markets. “To states seeking to nullify federal law and strip away that authority over this market, I say again: see you in court,” she said.

Separately, national gaming, tribal and labor groups recently urged lawmakers to add language to the CLARITY Act, now under Senate review, that would “explicitly prohibit event contracts linked to sports and casino-style gaming.”