Overview
- Building a Better California, seeded by Sergey Brin, has disclosed more than $100 million and reported a $5 million donation to the formal No campaign, sharply escalating the fight over the November ballot measure.
- Proposition 40 would impose a one-time 5% levy on residents with $1 billion or more in net assets, apply retroactively to Jan. 1, 2026, and backers say it would raise roughly $100 billion to fund healthcare, education and food assistance.
- Official analyses say the tax could deliver tens of billions in near-term revenue but warn it may produce ongoing annual revenue losses if wealthy residents and capital relocate out of state.
- Wealthy Californians have already shifted assets or residency, with reports that some have moved or dissolved California entities, and high-profile investors like Mark Cuban have publicly warned the measure could drive founders and investment away from the state.
- The campaign has split Democrats and produced a multi-front strategy from opponents who funded Propositions 41 and 42 to nullify Prop 40, reserved major ad buys, and turned the November vote into a test of whether social spending goals outweigh economic and fiscal risks.