The billionaire tax has three ballot fights attached

Proposition 40 asks California voters to approve a one-time 5% tax on the net worth of covered billionaires, with most of the proceeds going to public health care. But the campaign over that tax stretches across three spots on the November ballot.

Follow one committee's money. Building a Better California is the reported source of $103.5 million received by a No on 40 committee, $58.35 million by a Yes on 41 committee, and $112.8 million by a Yes on 42 committee. One source, three destinations—and two of them ask voters to say Yes to something else.

Props 41 and 42 would each change California's tax or spending rules in ways that could block Prop 40. For either to block 40, voters would have to pass both 40 and that other measure. The other measure would also need more Yes votes than 40, and a court would have to find a conflict. These are possible legal obstacles, not automatic vetoes.

The tax in the box marked 40

A Yes on 40 would tax 5% of the net worth of covered billionaires who were California residents on January 1, 2026. Real estate, pensions and retirement accounts would generally be excluded. The one-time payment would be due in 2027, with a costlier five-year option. Ninety percent of proceeds would support public health care; the rest would go to education, food assistance and administration. A No would leave this proposal unadopted.

The Legislative Analyst expects temporary revenue in the tens of billions, spread over several years, but says the amount and timing are hard to predict. It also projects a possible ongoing loss of less than $1 billion a year in income-tax revenue as taxpayers respond, plus administrative costs. Wealth and income are separate tax bases; both matter to the fiscal estimate. Official analysis.

Who funds the committee funding three campaigns?

Building a Better California raises money and contributes to committees taking positions on ballot measures. Here, it connects the committee opposing 40 with two committees supporting 41 and 42. It reported about $317.63 million in money and noncash support in the records we examined.

One reported contributor name stands out: Sergey Brin, at $102 million. The records also group about $40.24 million under Eric Schmidt’s name, $40 million under L. John Doerr III’s and $33.17 million under Patrick Collison’s. Schmidt’s amount includes noncash support. These are names reported in filings, not independently verified identities or a dollar-by-dollar trace from any person into a particular campaign.

The same money can appear when Building a Better California receives it and again when another committee receives its contribution. Adding both stages would count it twice. The chart shows what three recipients reported receiving from that common source; it does not show final spending or every committee on either side.

One committee taking the opposite positions is sponsored by Service Employees International Union–United Healthcare Workers West (SEIU-UHW), a healthcare union. It backs 40 and opposes 41 and 42, and reported about $32.48 million in money and noncash support. That is one committee’s funding, not three separate $32.48 million pools. Other committees also take positions, so these figures do not produce complete Yes/No totals.

Our Nevada follow-up encountered Building a Better California and two of these recipients. The older story covers a different period; the comparison notes explain why subtracting its figures from these would not measure new money.

The conditional second act

Prop 41 would add audits and could change how new special-tax spending counts under the state spending limit. Prop 42 would restrict new state personal-property ownership taxes and some retroactive taxes. For either 41 or 42 to stop 40, both it and 40 must pass, it must receive more Yes votes than 40, and a court must find a conflict. Only then could 40 be stopped from becoming law. Read the distinct rules in our 41 and 42 stories.

The money connects three campaigns. Voters will decide three propositions. If more than one passes, the last word on how they fit together could belong to a court.