A Google co-founder is spending $100 million to defeat California’s wealth tax. It could become one of his best investments

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Google co-founder Sergey Brin has funneled just over $100 million to a group trying to defeat a one-time state tax on California’s billionaires this November.

That seems like a lot of money, except Brin’s net worth – estimated around $270 billion, top five globally, according to Bloomberg’s billionaires index – means he’d face a nearly $14 billion hit under the tax, which proposes a 5% charge on the total assets of state residents with a net worth over $1 billion.

In those terms, $102 million for a chance to avoid the trouble seems like a decent investment ahead of California voters heading to the polls in November.

The battle over Proposition 40 has become one of the most expensive political fights in the country. Groups opposed to the measure have spent nearly $100 million on ads to reach voters, with most of their funding coming from Brin and other billionaires who oppose the tax.

The efforts from Brin and other Silicon Valley leaders are just the latest sign of escalating political activity from a new generation of megadonors, who have begun to deploy fortunes minted over the tech boom of the last two decades in attempts to shape public policy.

The wealth tax’s ultimate fate could affect the political fortunes of California Gov. Gavin Newsom, who is widely expected to launch a 2028 presidential bid and has publicly said he’ll vote no on Prop 40 , and whoever succeeds him – with the two candidates in the race, Democrat Xavier Becerra and Republican Steve Hilton, scheduled to participate in CNN’s gubernatorial debate Wednesday night, also having expressed opposition.

Manuel Orbegozo/Reuters

Gavin Newsom opposes a California wealth tax. He’s proposing a national billionaire tax instead

Tech and corporate leaders have threatened to move their residences, and even their businesses, out of California if the measure passes – potentially depriving the state of crucial jobs. Proponents, however, say the tax would be a critical counter to federal funding cuts to public programs.

The outcome of the referendum could also ripple across the remaining 49 states. There’s growing bipartisan backlash to tech and billionaires from an American public concerned about data centers, AI job losses and wealth inequality, who could see the tax as a model to try elsewhere. But red and blue states alike could also be interested in making a pitch for industry titans to relocate there if the measure passes, despite that growing tech animus.

Alphabet, Google’s parent company, did not respond to a request for comment from Brin, who sits on Alphabet’s board and has become central to the company’s AI efforts.

If approved, Prop 40 would allow the state to collect a one-time 5% tax on taxpayers and trusts valued at $1 billion or above. It would affect anyone living in the state as of the start of this year to prevent the wealthiest Californians from moving to avoid the tax.

“It’s too late to leave now,” said Emmanuel Saez, a professor at the University of California, Berkeley, and a key architect of the tax. “Because the ballot was announced in late November 2025, it left only one month for billionaires to leave. And we chose that design because we believe, based on the tax experts, that it’s basically impossible to sever residency with California within one month.”

Proponents say it’s a necessary response to federal health care spending cuts from the One Big Beautiful Bill Act, which they estimate leaves a shortfall of about $20 billion per year for California moving forward, threatening the state’s Medi-Cal program. They estimate the wealth tax could raise $100 billion, enough to cover the shortfall for about five years.

“Providers in places with vulnerable populations that depend a lot on Medicaid are going to be hit especially hard,” said Brian Galle, another professor at UC Berkeley who helped draft the language for Prop 40.

Polling on the tax suggests a potentially close vote. A UC Berkeley IGS poll last month found 48% of likely voters in favor, and 41% opposed. Another poll from the Public Policy Institute of California this month found that 52% of likely voters would vote yes on Prop 40 after reading the ballot title and label.

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While labor unions and progressive organizers push for the measure – which advocates note would target a total of just over 250 individuals with net worths over $1 billion – there are some powerful opponents.

Newsom explained his opposition in a Substack post after the initiative made the ballot, sympathizing with its creators but advocating instead for “a true minimum tax on billionaires” at the national level. He also noted that Prop 40 would not address other state budget needs like housing, childcare or education.

“We can’t let a single advocacy organization, however well-intentioned, write the state’s tax code on its own terms,” he wrote.

Opponents of the measure argue it could harm the state where they built their businesses and fortunes. Brin, who was born in Moscow, compared the tax in a rare comment to The New York Times to the society he fled as a child.

“I fled socialism with my family in 1979 and know the devastating, oppressive society it created in the Soviet Union,” he said. “I don’t want California to end up in the same place.”

He has emerged as one of the largest financial backers of the effort to block the tax.

According to state campaign finance records, he donated $102 million over the last year to the group Building a Better California, which has booked more than $50 million in ad time per AdImpact data.

The group is supporting a pair of rival initiatives, Proposition 41 and Proposition 42, that would limit the scope of new state taxes. If either measure passes and receives more votes than Prop 40, it could supersede the wealth tax. Building a Better California also says it supports measures to expand access to affordable housing in the state — at a time when the AI boom has contributed to surging housing costs in the San Francisco area.

Building a Better California is also among the top funders of the main “No” committee opposing Prop 40.

A cohort of other wealthy Californians also shelled out millions in the effort to block the tax, including venture capitalist Peter Thiel; John Doerr, chairman of the venture capital firm Kleiner Perkins; and Patrick Collison, CEO of the digital financial services company Stripe, according to campaign finance records.

That financial firepower has enabled the coalition against the wealth tax to reserve nearly $100 million worth of ad time this year, according to AdImpact data, against only about $100,000 in ad support in favor of the tax. Proponents have also spent several hundreds of thousands of dollars on get-out-the-vote efforts and campaign literature, according to Meghan Finegan, a representative for the “Yes” campaign.

With their airtime, opponents are running waves of ads urging voters to reject the tax, using a variety of arguments. Some ads , appealing to blue California’s broadly liberal electorate, note that Planned Parenthood and several non-healthcare unions oppose the wealth tax.

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The bill targets California’s billionaires’ assets (with some exceptions ) rather than just their incomes, given that many in Silicon Valley opt to take minimal salaries and maintain most of their wealth in the form of stocks, property and other assets. That could subject them to intrusive probing of their assets and encourage wealthy business leaders to leave the state, said Robert Lapsley, president of the California Business Roundtable.

“We already have all the highest taxes in the country — gas taxes, income taxes,” Lapsley said. “To create and implement an asset tax on top of that is going to drive, and is driving, the job creators that we have in this state out of here.”

Brin’s spending on the wealth tax marks the latest example of his rightward shift in both political engagement and spending — a move that other prominent tech leaders have also made in recent years as Republicans largely champion a more hands-off approach to tech regulation.

During Trump’s first administration, Brin protested the president’s travel ban on immigrants from several Muslim-majority countries, noting his own experience as an immigrant.

But there’s been a notable pivot since Trump’s reelection: Brin attended Trump’s second inauguration , dined with other tech leaders at the White House during the current administration and last year donated hundreds of thousands of dollars to the Republican National Committee. While he initially backed a pro-tech Democratic candidate in California’s gubernatorial primary this year, he also threw his financial support behind Hilton, a Trump-backed Republican.

Leaders like Brin “continue to see themselves as outsiders, young guns who aren’t part of the system,” who hope they can convince Californians that they’re all on the same side building for the future and to oppose the wealth tax, said University of Washington historian Margaret O’Mara, who tracks the tech industry. But Silicon Valley leaders’ longtime techno-optimist values are running up against an American public that is increasingly skeptical of tech’s influence on their lives.

Saez, one of the architects of the tax, also sees the fight having a broad impact.

“Prop 40 is going to be, if it passes, I see it as this historical turning point,” he said, adding that the tax could become a model for other states, “the first time when democracy succeeds in fighting back against billionaires.”

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谷歌联合创始人谢尔盖·布林已向一个试图阻止加州今年 11 月对亿万富翁征收一次性州税的团体捐赠了超过 1 亿美元。

这笔钱看起来很多，但布林的净资产——据彭博亿万富翁指数估计约为 2700 亿美元，位列全球前五——意味着，根据这项税收政策，他将面临近 140 亿美元的损失。该政策提议对净资产超过 10 亿美元的州居民的总资产征收 5% 的税。

从这个角度来看，在加州选民即将于 11 月投票之际，花费 1.02 亿美元来避免麻烦似乎是一项不错的投资。

围绕第40号提案的争论已成为美国历史上最昂贵的政治斗争之一。反对该提案的团体已花费近1亿美元用于广告宣传，以争取选民支持，而他们的大部分资金来自布林和其他反对这项税收的亿万富翁。

布林和其他硅谷领导人的努力，只是新一代巨额捐助者政治活动日益活跃的最新迹象。这些捐助者开始利用过去二十年科技繁荣时期积累的财富，试图影响公共政策。

财富税的最终命运可能会影响加州州长加文·纽森的政治前途。纽森被广泛认为将参加 2028 年总统竞选，并已公开表示他将对第 40 号提案投反对票。纽森的继任者也会受到影响——目前，民主党候选人泽维尔·贝塞拉和共和党候选人史蒂夫·希尔顿计划于周三晚参加 CNN 的州长辩论，他们也都表示反对。

曼努埃尔·奥尔贝戈佐/路透社

加文·纽森反对加州征收财富税。他提议改为征收全国性的亿万富翁税。

科技和企业高管威胁称，如果这项法案获得通过，他们将把住所甚至企业迁出加州，这可能会使加州失去关键就业岗位。然而，支持者表示，这项税收将是应对联邦政府削减公共项目资金的重要手段。

公投结果也可能波及其余49个州。美国民众对数据中心、人工智能导致的就业岗位流失和财富不均等问题日益担忧，两党人士对科技公司和亿万富翁的抵制情绪也日益高涨，他们可能将这项税收视为其他州可以借鉴的模式。但即便面对日益增长的科技行业敌意，如果这项措施获得通过，无论是共和党执政的州还是民主党执政的州，都可能积极争取行业巨头迁址。

谷歌母公司 Alphabet 没有回应布林的置评请求。布林是 Alphabet 的董事会成员，并且已成为该公司人工智能工作的核心人物。

如果获得批准，第40号提案将允许加州对资产超过10亿美元的纳税人和信托基金一次性征收5%的税。该提案将影响今年年初居住在加州的所有人，以防止加州最富有的人为了避税而迁居他州。

“现在离开已经太晚了，”加州大学伯克利分校教授、该税项的主要设计者之一伊曼纽尔·萨埃兹说道。“由于投票是在2025年11月下旬才宣布的，亿万富翁们只剩下一个月的时间离开。我们之所以选择这样的方案，是因为根据税务专家的意见，我们认为在一个月内完全脱离加州的居住地几乎是不可能的。”

支持者认为，这是对联邦政府削减医疗保健支出（根据《一项宏伟法案》）的必要回应。他们估计，该法案将导致加州每年约200亿美元的资金缺口，威胁到该州的医疗补助计划（Medi-Cal）。他们估计，这项财富税可以筹集1000亿美元，足以弥补大约五年的资金缺口。

“那些弱势群体严重依赖医疗补助的地方的医疗服务提供者将受到特别严重的打击，”加州大学伯克利分校的另一位教授布莱恩·加勒说道，他曾参与起草第 40 号提案的措辞。

关于这项税收的民调显示，投票结果可能非常接近。加州大学伯克利分校IGS上个月的民调显示，48%的潜在选民支持这项税收，41%反对。加州公共政策研究所本月进行的另一项民调发现，52%的潜在选民在阅读了选票标题和说明后，表示会投票支持第40号提案。

Charly Triballeau/AFP/Getty Images

尽管工会和进步组织者力推这项措施——支持者指出，该措施将针对净资产超过 10 亿美元的 250 多名个人——但也存在一些强大的反对者。

纽森在Substack上发帖解释了他反对该提案的原因，该提案进入投票程序后，他表示同情提案发起人，但主张在国家层面“对亿万富翁征收真正的最低税”。他还指出，第40号提案无法解决州预算的其他需求，例如住房、儿童保育或教育。

“我们不能让任何一个倡导组织，无论其初衷多么良好，按照自己的意愿来制定该州的税法，”他写道。

反对者认为，这项措施可能会损害他们建立事业和财富的州。出生于莫斯科的布林在接受《纽约时报》罕见采访时，将这项税收比作他童年时期逃离的那个社会。

“1979年，我和家人一起逃离了社会主义，我深知苏联社会主义制度造成的毁灭性和压迫性，”他说。“我不想让加州重蹈覆辙。”

他已成为阻止这项税收行动的最大金主之一。

根据州竞选财务记录，他在过去一年中向“建设更美好的加州”组织捐赠了 1.02 亿美元，根据 AdImpact 的数据，该组织已预订了价值超过 5000 万美元的广告时间。

该组织支持两项相互竞争的提案——第41号提案和第42号提案，这两项提案旨在限制新增州税的范围。如果其中任何一项提案获得通过，且得票数超过第40号提案，则可能取代财富税。“建设更美好的加州”组织还表示，他们支持扩大加州经济适用房供应的措施——尤其是在人工智能热潮导致旧金山地区房价飙升之际。

“建设更美好的加州”组织也是反对第 40 号提案的主要“反对”委员会的主要资助者之一。

据竞选财务记录显示，包括风险投资家彼得·蒂尔、风险投资公司凯鹏华盈董事长约翰·多尔以及数字金融服务公司 Stripe 首席执行官帕特里克·科里森在内的其他加州富人也花费了数百万美元来阻止这项税收。

据AdImpact的数据显示，凭借雄厚的财力，反对财富税的联盟今年已预定了价值近1亿美元的广告时段，而支持该税的阵营仅获得了约10万美元的广告支持。据“赞成”阵营的代表梅根·芬尼根（Meghan Finegan）称，支持者们还在选民动员和宣传材料上花费了数十万美元。

反对者利用电视和广播资源，投放大量广告，敦促选民否决这项税收，并列举了各种论点。一些广告针对加州普遍倾向自由派的选民，指出计划生育协会和一些非医疗保健行业的工会都反对这项财富税。

莱斯特·科恩/盖蒂图片社

鉴于硅谷许多亿万富翁选择领取极低薪水，并将大部分财富以股票、房产和其他资产的形式持有，该法案针对的是加州亿万富翁的资产（部分情况除外），而不仅仅是他们的收入。加州商业圆桌会议主席罗伯特·拉普斯利表示，这可能会使他们的资产受到侵入性审查，并促使富有的商业领袖离开加州。

拉普斯利说：“我们已经拥有全国最高的税收——燃油税、所得税。在此基础上再设立和实施资产税，将会把，而且正在把我们州的就业创造者赶走。”

布林在财富税上的支出标志着他在政治参与和支出方面向右倾斜的最新例证——近年来，其他一些杰出的科技领袖也采取了类似的举措，因为共和党人大多主张对科技监管采取更加放任的态度。

在特朗普的第一任期内，布林抗议总统对来自几个穆斯林占多数国家的移民实施的旅行禁令，并指出他自己作为移民的经历。

但自特朗普连任以来，情况发生了显著变化：布林出席了特朗普的第二次就职典礼，在本届政府执政期间与白宫其他科技领袖共进晚餐，并在去年向共和党全国委员会捐赠了数十万美元。虽然他最初在今年的加州州长初选中支持一位亲科技的民主党候选人，但他也向特朗普支持的共和党候选人希尔顿提供了资金支持。

华盛顿大学历史学家玛格丽特·奥马拉（Margaret O'Mara）长期关注科技行业，她表示，像布林这样的领导者“仍然把自己视为局外人，是体制外的年轻精英”，他们希望能够说服加州民众，他们为了共同的未来而站在同一阵线，并反对财富税。然而，硅谷领导者长期以来秉持的技术乐观主义价值观，正与日益怀疑科技对其生活影响的美国公众发生冲突。

萨埃斯是这项税收政策的设计者之一，他也认为这场斗争会产生广泛的影响。

“如果第 40 号提案获得通过，我认为这将是一个历史性的转折点，”他说道，并补充说，这项税收可能会成为其他州的典范，“这是民主第一次成功地反击亿万富翁。”