California voters face a complex and highly funded battle over Proposition 40, a wealth tax measure targeting billionaires that will appear on the November ballot. The proposal would impose a one-time 5% tax on the net worth of billionaires who resided in California as of January 1, seeking to raise revenue in response to anticipated federal healthcare funding cuts. Alongside Proposition 40, two related measures—Propositions 41 and 42—aim to neutralize or limit its effects through changes in tax law.
Proposition 40 was introduced by the Service Employees International Union-United Healthcare Workers West as a response to cuts signed into law by the Trump administration that are expected to reduce California’s healthcare budget by approximately $100 billion. Supporters argue that the resulting shortfalls could cause millions of Californians to lose health insurance, force closures of hospitals and emergency rooms, and endanger vulnerable patients. Union leaders characterize the wealth tax as an urgent and necessary step to address a looming crisis in healthcare funding.
The campaign supporting the billionaire tax has raised around $34.3 million, almost entirely from the union, with much of the funding previously spent on qualifying the measure for the ballot. Their outreach efforts include public events and media coverage, featuring endorsements from figures such as Senator Bernie Sanders, who has described the measure as a challenge to economic inequality and the concentration of wealth.
In contrast, opposition to Proposition 40 is significantly better funded, with more than $316 million raised, predominantly from several high-profile California billionaires. Tech entrepreneurs Sergey Brin, Eric Schmidt, and venture capitalist L. John Doerr are among the largest donors, each contributing tens of millions of dollars. Opponents argue that Proposition 40 threatens California’s budget stability, potentially harming healthcare, education, and the broader economy. They contend that the measure’s retroactive application to individuals based on their residency as of the beginning of the year raises serious legal and fiscal concerns.
The two countermeasures, Propositions 41 and 42, are presented by backers as efforts to promote fiscal accountability and protect individual retirement assets from new taxation. Supporters of these initiatives say they seek to reduce government waste and safeguard personal savings, while proponents of Proposition 40 view them as deliberate attempts to undermine the wealth tax under the guise of taxpayer protection.
The campaign environment is marked by an unprecedented scale of spending, with opponents deploying money across a wide array of platforms, including television, streaming services, mailers, social media influencers, and even digital video games. Pro-40 campaigners claim this flood of advertising exemplifies the power and priority the ultra-wealthy place on defeating the measure. Critics of the wealth tax, meanwhile, emphasize the need for pragmatic solutions that do not destabilize the state’s volatile budget, noting divisions even among some Democrats who support wealth taxation in principle but oppose this specific proposal.
Experts warn that the ballot measures invite legal challenges, particularly around the retroactive nature of the tax. Election law analysts describe the situation as complicated and uncertain, highlighting the unusual interplay of multiple related initiatives that could reshape California’s tax framework depending on voter outcomes.
As California voters evaluate these competing propositions, the outcome could have lasting implications for the state’s approach to taxation, economic equity, and funding for public services.