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Google co-founder Sergey Brin and a group of fellow technology billionaires have raised $316.7 million to defeat California’s proposed one-time tax on billionaires, turning the Nov. 3 vote into one of the most expensive ballot fights in the state’s history.
Total contributions on both sides of Proposition 40 have passed $351 million, and about 90% of that money is going toward killing the measure. Supporters have raised about $34.3 million, nearly all of it from the Service Employees International Union-United Healthcare Workers West, the health care workers’ union that put the tax on the ballot. The campaign had $1.6 million in cash left as of Oct. 17, after spending most of its money gathering signatures.
Brin remains the largest single donor, with more than $100 million given to groups fighting the tax. Eric Schmidt, Google’s former chief executive, and John Doerr, the Silicon Valley venture capitalist, have each given $40 million. Ripple co-founder Chris Larsen and PayPal co-founder Peter Thiel are also among the opponents’ backers.
Suzanne Jimenez, chief of staff at SEIU-UHW, defended the tax as “an emergency response” to a looming crisis in health care funding.
Rob Stutzman, a Republican strategist, said the measure’s backers “came to that fight with a butter knife against a nuclear arsenal.” He added that “money does not guarantee a win.”
The measure would impose a one-time 5% tax on the net worth of Californians worth more than $1 billion who lived in the state on Jan. 1, 2026, a group of about 250 people. The union says it would raise about $100 billion, mostly for Medi-Cal, the state’s health program for low-income residents, with some money for food aid and public schools. The state’s Legislative Analyst’s Office has said it would likely bring in tens of billions of dollars over several years but could cost the state hundreds of millions of dollars or more a year in lost income tax if wealthy residents leave.
Much of the opposition money is also backing two rival measures on the same ballot. Proposition 41 would require audits of new special taxes and limit how their revenue is spent. Proposition 42 would bar new state taxes on personal property such as retirement accounts, investments and business stakes. Under California law, when two conflicting measures both pass, the one with more votes takes effect, so Proposition 42 could cancel the billionaire tax even if voters approve it.
Governor Gavin Newsom, who has opposed the billionaire tax for months, endorsed Proposition 42 on Oct. 9, as Billionaires.Africa reported. Some senior Democrats and labor groups have also lined up against Proposition 40.
Voters have looked split. A Public Policy Institute of California survey of 1,103 likely voters, taken Sept. 4 to 10, found 52% backing Proposition 40 and 42% opposed. The same poll found 51% support for Proposition 41 and 54% for Proposition 42, which would be enough to block the tax. A more recent Citrin Center-Politico poll put support for Proposition 40 at 46% and opposition at 43%.
“It’s rare for such a broad coalition to unite around any single cause in California,” the opposition campaign said in a statement.
Brin, 53, co-founded Google with Larry Page in 1998 while both were graduate students at Stanford University. He is one of the richest people in the world, and his tax bill under the measure would run into billions of dollars. Billionaires.Africa reported on Sept. 30 that his spending against the tax had reached $102 million.
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