Google co-founder Sergey Brin has now spent $100 million to fight the billionaire tax
Google co-founder Sergey Brin has donated a further $20 million to Build a Better California, an anti-tax campaign group opposing the state's proposed "billionaire tax," bringing his total spending against the measure to over $100 million. The move highlights how some of Silicon Valley's wealthiest figures are mobilising to block a levy that would target around 200 of California's richest residents, at a time when the state faces significant healthcare funding shortfalls.
Prop 40, which Californians will vote on in November, would impose a one-off 5% tax on billionaires' net worth, raising funds primarily for healthcare programmes as the state's Medicaid system braces for the loss of up to $30 billion in federal funding. Brin, worth an estimated $267 billion, would reportedly owe around $13.3 billion under the measure; the group he funds has proposed rival ballot measures to effectively block it. Other tech figures including Mark Zuckerberg, Travis Kalanick, Peter Thiel and Larry Page have reportedly relocated away from California, while Governor Gavin Newsom has criticised the tax's potential economic fallout but backed a national billionaire tax instead. Not all billionaires oppose it, however — Nvidia's Jensen Huang has said he is "perfectly fine" paying his roughly $8 billion share.
In short
- Brin has spent over $100m fighting California's proposed billionaire tax
- Prop 40 would levy a one-off 5% wealth tax on ~200 billionaires
- Californians vote on the measure in November; reactions among billionaires are mixed
Steelman: both sides, in good faith
The strongest fair case each way — we don't pick a winner.
The case for
California faces an existential healthcare funding crisis, with a potential $30 billion loss in federal Medicaid support. The state's billionaires have accumulated their fortunes partly through California's exceptional infrastructure and business environment, making a modest one-time 5% net worth tax on approximately 200 of them both economically sound and morally justified when public services face dire shortfalls. The fact that some billionaires, such as Jensen Huang, have indicated willingness to pay demonstrates that the tax need not cause economic collapse, and progressive taxation based on ability to pay represents a reasonable response to genuine public need.
The case against
California's Proposition 40 represents a flawed approach to a genuine fiscal problem, raising fundamental questions about constitutionality and implementation of a tax on unrealised net worth rather than income. Multiple billionaires have already demonstrated their willingness to relocate, and the tax would likely accelerate capital flight, ultimately shrinking California's overall tax base and reducing funding for the very programmes it aims to support. Governor Newsom himself has expressed scepticism, preferring a federal billionaire tax instead—a targeted levy on one state's wealthiest residents risks economic harm without delivering proportionate benefit, potentially simply displacing residents rather than generating genuine revenue.
Explained simply
California’s proposed measure would charge the state’s billionaires a one-off tax of 5% of their net worth. Voters are due to decide on it in November, and the money would go mainly towards healthcare programmes.
The proposal comes as California’s Medicaid system faces the possible loss of up to $30 billion in federal funding. It would affect around 200 of the state’s richest residents, including Sergey Brin, a co-founder of Google.
Some wealthy technology figures have funded a campaign against the measure, while others have moved out of California. Governor Gavin Newsom has raised concerns about its possible economic effects, and Nvidia chief Jensen Huang has said he is willing to pay his estimated share.