Overview
- Polls released Oct. 28 show support for Proposition 40 slipping below 50 percent, with PPIC finding 46% in favor and SurveyUSA near 44%, reversing earlier leads for the measure.
- Opponents have poured hundreds of millions into the campaign, including more than $100 million reportedly from Sergey Brin, and that late spending has been credited with shifting voter sentiment.
- Backers say the one‑time 5% levy on residents with net worth above $1 billion would fund Medi‑Cal and related programs, but rival measures on the same ballot—Propositions 41 and 42—could invalidate Prop 40 if they win or outpoll it.
- Tax experts and analysts warn Prop 40’s retroactive Jan. 1, 2026 residency snapshot and novel rules for valuing illiquid assets invite complex administration, possible billionaire departures that cut revenue, and rapid court challenges.
- The fight has split California Democrats, with organized labor backing the measure and Governor Gavin Newsom opposing it, and observers say the outcome will shape state budgeting and the national debate over wealth taxes.