A judge has granted Washington’s request to block Kalshi from offering its so-called event contracts in the state, saying the prediction markets platform likely violated the state’s gambling laws.

In a decision on Monday, Judge John McHale of the King County Superior Court granted Washington’s motion for a preliminary injunction.

McHale said the state showed “a likelihood of actual and substantial injury to Washington consumers from illegal gambling activities” if no injunction were issued. He also said the public interest and potential harm to consumers outweighed harm to Kalshi.

Judge John McHale said the state showed “a likelihood of actual and substantial injury to Washington consumers from illegal gambling activities” if no injunction were issued.

Washington joined Massachusetts, Michigan and Nevada in winning court orders restricting Kalshi’s activities.

New York won a similar order on July 8, when a federal judge rejected Kalshi’s bid to block enforcement of that state’s gambling laws against the platform.

The US Commodity Futures Trading Commission, meanwhile, has claimed exclusive jurisdiction over the industry, and challenged regulatory activity in at least nine states.

In April, a divided federal appeals court cited the CFTC’s authority in blocking New Jersey gaming authorities from regulating Kalshi’s sports event contracts.

“States don’t have jurisdiction to regulate prediction markets,” Kalshi said in a statement on Tuesday. “We’re disappointed to see Washington state continue wasting taxpayer dollars.”

The judge said he plans to issue an order implementing the injunction on Aug. 5.

Washington Attorney General Nick Brown praised the decision, calling it “the first step toward holding Kalshi accountable.” AFP via Getty Images

“Kalshi padded their pockets as they promoted illegal betting on sports, elections, the total number of measles cases this year, what will witnesses say during a child trafficking hearing, and even natural disasters,” Washington Attorney General Nick Brown said in a statement. “This victory is the first step toward holding Kalshi accountable.”

Prediction markets such as Kalshi and Polymarket let people wager on the outcome of events such as sports and elections.

They have soared in popularity since the 2024 US presidential election, when they did a better job than pollsters in predicting Republican Donald Trump’s victory over Democrat Kamala Harris.

About $19.04 billion was wagered through Kalshi and Polymarket on the recently completed soccer World Cup, according to data tracker Dune Analytics.