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California wealth-tax proposals, documents, competing arguments and developments.
Source shelf
- California legislative information ↗Primary source
- California Secretary of State initiatives ↗Primary source
Latest approved updates
60 itemsProposal to Tax Billionaires Ignites a Political Fight in California | KQED →
California Billionaire Tax Will Be on November’s Ballot, Along With These 13 Measures | KQED →
Splitting With State Party, San Francisco Democrats Oppose Billionaire Tax | KQED →
2026 Berkeley IGS Poll Releases →
California Billionaire Tax Nears the November Ballot | KQED →
California Voters Appear to Support a Billionaire Tax, Split on Proposed Voter ID Law | KQED →
California Billionaire Tax Has Strong Support of Democratic Voters, New Poll Shows | KQED →
California Secretary of State Shirley N. Weber, Ph.D., Announces New Measure Eligible for November 2026 General Election Ballot. Imposes one-time tax on certain individuals and trusts. Initiative constitutional amendment and statute. :: California Secretary of State →
New Polling Sheds Light on November Ballot | KQED →
What is the California 2026 Billionaire Tax Act? →
The California Billionaire Tax Act: Constitutional Limits on Implementation | Thought Leadership | June 2026 | Baker Botts →
Can Sanders' Billionaire Tax Survive Constitutional Review? →
California’s Proposition 40 Billionaire Tax: What Family Offices Should Watch Before the November 2026 Ballot | ArentFox Schiff →
Billionaire Tax Explained: What Proposition 40 Would Mean for California →
California Billionaires: Wealth, Taxes, and Wealth Tax Revenue Estimates →
The Politics and Promise of a Billionaire Tax | Stanford Law School →
Update on the California 2026 Billionaire Tax Act | Thought Leadership | May 2026 | Baker Botts →
California’s proposed Billionaire Tax Act ballot initiative →
California 2026 Billionaire Tax Act | Thought Leadership | December 2025 | Baker Botts →
The Legal Challenges to California’s Proposition 40, the 2026 Billionaire Tax Act – California Globe →
New tax on the wealth of billionaires. [Ballot] →
The California Billionaire Tax Act: Delayed, Contested, and Uncertain Revenue | Thought Leadership | June 2026 | Baker Botts →
California's Proposed Billionaire Tax: What You Need to Know | Insights | Holland & Knight →
Union leader behind California billionaires' tax proposal accused of threatening, harassing women →
Prop 40 is dividing CA labor unions and experts argue the fight goes well beyond a billionaire tax →
Opinion | California’s Wealth Tax Will Drive Talent Out of the State - WSJ →
Close to Home: Tax California billionaires now - The Press Democrat →
Opinion | Five California propositions ask the same question: Who should pay billions in taxes? →
Constitutional Flaws of California’s Proposed Wealth Tax →
California Democrats buck Newsom and union allies by endorsing populist billionaire tax →
Opinion | California’s billionaire tax measure risks long-term growth for a sugar-high solution →
Proposition 40: Billionaire tax →
California’s 2026 Billionaire Tax Act: What High-Net-Worth Taxpayers Need to Know →
Tax the rich, Gavin Newsom says to the nation. In California, he walks a finer line →
Opinion | California voters will decide 14 ballot measures, billionaire tax included. There could've been more →
California Gov. Gavin Newsom proposes federal billionaire tax and AI "public equity" fund →
California voters to decide in November on proposal to increase taxes on billionaires →
It’s official. California voters will decide whether to tax billionaires →
Your November ballot: See the 14 measures California voters will decide →
California’s proposed billionaire tax: what you need to know →
California ‘billionaire tax’ makes ballot despite opposition from tech moguls →
California billionaire tax proposal clears signature hurdle for November ballot →
Opinion | As ballot deadline nears, will California's billionaire tax actually go to voters? →
Mid-Year Movers and the California Wealth Tax →
Why California progressives’ push to tax the rich could worsen the budget problem →
California billionaires’ tax is a no-brainer for liberal Democrats, right? Wrong. →
California’s Proposed Billionaire Wealth Tax and the Question of State Residency →
Opinion | Government money made Silicon Valley’s tech titans rich. A billionaire tax won't hurt them →
Expert Report on the California 2026 Billionaire Tax: Revenue, Economic, and Constitutional Analysis →
California’s Proposed 2026 Billionaire Tax Act: What You Need to Know →
Bernie Sanders and Gavin Newsom become adversaries over push to tax California billionaires →
Opinion | Billionaires aren’t going to flee California. Others will without a budget fix →
New California Wealth Tax Heads to the 2026 Ballot: Who Would Pay, What's at Stake and What Happens Next →
Health advocates to Newsom: Find new money or let millions lose Medi-Cal coverage →
California’s Proposed ‘Billionaire Tax’: Nine Things to Know →
The Proposed California Wealth Tax Is Far Higher than 5 Percent →
What to Know About California's Proposed 'Billionaire Tax' →
Peter Thiel makes $3m donation to fight California’s proposed billionaire tax →
Mayor Matt Mahan of San Jose, Silicon Valley's largest city, criticizes proposed California billionaires' tax →
Can California Legally Tax Billionaires’ Wealth? What the New Measure Triggers →
Edition record
- California Billionaires Tax →Selected reporting