Minnesota Gov. Tim Walz has signed the nation's first law banning prediction market sites from operating in the state, the most far-reaching crackdown on massively popular services like Kalshi and Polymarket.

It comes as states confront a growing standoff with the Trump administration over how to regulate the industry, which allows people to bet on virtually anything.

The new state law makes it a crime to host or advertise a prediction market, which it defines as a system that lets consumers place a wager on a future outcome, like sports, elections, weather, live entertainment, someone's word choice and world affairs.

The prohibition extends to services supporting prediction markets, like virtual private networks, that could allow consumers to disguise their location and get around the ban.

It would force prediction market sites like Kalshi and Polymarket to leave the state, or face possible felony charges. The law takes effect in August.