California billionaire tax: Prediction markets show slide in ballot measure odds

Chances that a proposed billionaire tax will appear on California’s ballot dropped from 88% to 35.5% over the past week on prediction markets platform Kalshi.

The plunge arrives on the heels of reports from Politico and Bloomberg News that Gov. Gavin Newsom is pushing to stop the proposed tax from appearing on November’s ballot before a June 25 deadline.

The proposal, backed by the Service Employees International Union — United Healthcare Workers West, calls for a one-time 5% tax on a billionaire’s net worth. 

The union argues that taxing billionaires will support the state’s healthcare system after massive federal funding cuts.

“The tax would be paid only by Californians worth more than $1 billion — which is about 200 people who hold a combined wealth of $2 trillion,” the union’s website states.

The union said it submitted more than 1.5 million signatures from California voters to have the billionaire tax act on the ballot. Only 875,000 signatures are required. 

Newsom’s reported opposition to the billionaire tax measure comes as he’s seriously considering the presidential election. On Monday, the governor accused President Donald Trump of ordering the Department of Justice to investigate him and his wife.

In a post on X, Newsom said that Trump was driven to target him because of the fact that “I am considering running for President.”

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