Billionaires Channel $300 Million Into California Prop. 40 Fight

Billionaires are directing $300 million toward an effort to defeat California's Proposition 40, a proposed one-time tax on wealthy residents that voters will consider in November.

The measure would impose a one-time 5% levy on the net worth of about 250 billionaires who resided in California at the start of 2026. A majority of the revenue would be directed to health care.

Recent polling shows the measure has more support than opposition, though support remains below a majority. California voters are scheduled to decide Proposition 40 on Nov. 3, 2026.