Early public opinion shows notable support, with a UC Berkeley poll indicating about half of voters back the tax.

Even as advocates push forward, there are acknowledged challenges of wealth taxation, such as administration hurdles and revenue volatility, with some tech billionaires backing efforts to block or weaken the tax.

Proponents aim to raise roughly $100 billion over five years, while billionaire opponents, including Sergey Brin, are funding countermeasures to block new personal-property taxes and boost revenue audits.

Some allied lawmakers advocate a broader federal approach to billionaire taxation, signaling the issue’s potential relevance beyond California.

If multiple tax measures pass, the one with the most affirmative votes will prevail; Brin and others have contributed over $100 million to Building a Better California, while supporters have raised about $25.7 million.

Reports indicate several California billionaires considered leaving the state or moved assets to avoid the tax, though Nvidia’s Jensen Huang publicly supports staying and argues for leveraging California’s talent pool.

A coalition of tech leaders and labor groups, Building a Better California, is backing a one-time billionaires’ wealth tax with the aim of funding healthcare and offsetting Medicaid-like costs, while opposing alternative policies viewed as weaker on wealth concentration.

The measure has become a flashpoint in intra-Democratic politics in California, highlighting deep divisions as supporters and opponents spar ahead of the 2026 elections.

Backers say the initiative has gathered more than 1.5 million signatures, signaling strong organizing by the SEIU-UHW healthcare union to qualify for the 2026 ballot.

Economic projections are contested: supporters expect a sizable revenue windfall, but analysts warn gains could shrink if ultra-wealthy residents move assets or residents leave the state.

The debate includes critiques of tax avoidance by ultra-wealthy families and arguments for greater scrutiny of rich individuals’ taxes.

The measure targets total wealth, including stocks, private business equity, and intellectual property, but excludes directly owned real estate.