Google co-founder Sergey Brin has now spent more than nine figures fighting the planned California wealth tax.
According to a submission As of Friday, Brin donated an additional $20 million to Building a Better California, a PAC and political advocacy group that opposes the state’s billionaire tax and supports other pro-business policies and housing and infrastructure affordability. He has now donated a total of $102 million to the group.
Proposal 40Voted in November, would impose a one-time 5% tax on California’s 200 billionaires, with 90% of the proposed measure’s revenue going to the state’s health care program and 10% to education, food aid and government. Brin, with one Net worth of nearly $270 billioncould owe more than $13 billion because of the tax.
California, the most populous state, has become the epicenter of the discussion about the K-shaped economy, or the different fates of people with and without wealth. While the Golden State has a GDP of $4 trillion, making its economy about the size of the United Kingdom, that is also the case 18% of residents live below the poverty linethe highest in the country, due in part to the high cost of living.
Billionaires oppose Prop 40
The ballot measure has caused uproar among some of California’s wealthiest people, such as former Google CEO Eric Schmidt and PayPal Co-founder Peter Thiel, both of whom have donated to organizations opposing the measure. Brin compared the proposal to his socialist Soviet upbringing.
“I fled socialism with my family in 1979 and know the devastating, oppressive society it created in the Soviet Union. I don’t want California to end up in the same place,” he said told that New York Times in a statement in April.
California Gov. Gavin Newsom has joined these tech billionaires in fighting the measure, arguing the tax would hurt the state by eroding its tax base and ultimately reducing critical revenue for social services.
“The fact is that this actually reduces investment in education,” Newsom said in one Bloomberg Businessweek interview Earlier this year. “It will reduce investment in teachers, librarians and child care. It will reduce investment in fire and police departments.”
In some ways, opposition to Prop 40 could be a self-fulfilling prophecy, like billionaires like Brin Relocating business units from California in favor of states without similar property taxes. According to state records, Brin now lists Nevada as his residence. Larry Page, who co-founded Google alongside Brin, did it converted several of its assets from California, including Koop, his family office, which was founded in December 2025 in Delaware. Oceankind, a non-profit marine research organization Founded in 2018 by Page’s wife Lucy Southworthwas also founded in Delaware around the same time. For his part, Brin reportedly said bought a house for $51 million near Miami Beach in March.
Will a property tax hit California?
There is no clear evidence yet that these billionaires’ concerns about California’s future are well founded. On the one hand, the six billionaires expected to leave California – Brin, Page, Thiel and former auto loan magnate Don Hankey Above CEO Travis Kalanick and director Steven Spielberg together would have generated around $27 billion in tax revenue a quarter of the $100 billion The proposal is expected to result in tax increases over five years.
On the other hand, billionaires were already paying so little in California income taxes when they left maybe not as much punch as expected. A working paper released in May by the National Bureau of Economic Research found that billionaires resident in the state paid $4.1 billion in income taxes last year, about 0.2% of their total $2 trillion net worth. That means that even if every billionaire were to leave the state, it would take about 25 years for income tax losses to offset the $100 billion that California is expected to receive from the tax. Even if a quarter of the state’s wealthiest residents were caught up in a billion-dollar mass exodus, it would take a century to reach the $100 billion coin.
“The proposed one-time California billionaire tax of 5%, payable over 5 years, is both low relative to the wealth gains of California billionaires and high relative to the taxes they currently pay,” the authors wrote.