A California labor union said Monday it has collected enough signatures to place a proposed billionaire tax on the November ballot.

The measure would impose a one-time 5% tax on individuals with a net worth exceeding $1 billion who lived in California as of Jan. 1, 2026.

The Service Employees International Union Healthcare Workers West said it gathered more than 1.5 million signatures, well above the roughly 875,000 required, according to the Associated Press. The California Secretary of State must still verify the signatures before officially placing the measure on the ballot.

The proposal aims to raise $100 billion, largely to offset federal cuts to Medicaid and food assistance under a law President Donald Trump signed last year.

Benzinga reached out to SEIU Healthcare Workers West for comment, but did not immediately receive a response.

Who's Fighting It

Google (GOOGL  ) (GOOG  ) co-founder Sergey Brin has donated $57 million to Building a Better California, a committee opposing the measure, the New York Times reported. The group has raised over $90 million from fewer than a dozen donors. Brin moved to the Nevada side of Lake Tahoe before a Dec. 31 deadline to escape the tax.

Palantir Technologies Inc. (PLTR  ) chairman Peter Thiel donated $3 million to a committee opposing the measure. Venture capitalist Chamath Palihapitiya warned on X that the proposal is "actually an Everyone Tax," arguing it contains mechanisms to expand beyond billionaires without voter approval.

Democratic Gov. Gavin Newsom and Silicon Valley leaders have opposed the measure, warning it will drive wealthy residents out of the state.

Who's Already Left

Uber co-founder Travis Kalanick said he moved to Texas on December 18. Meta Platforms Inc. (META  ) CEO Mark Zuckerberg purchased a Miami estate estimated at $150 million to $200 million. NVIDIA Corp. (NVDA  ) CEO Jensen Huang has taken the opposite stance, publicly urging people to stay in California despite its high taxes.