Billionaires shatter spending record to fight California wealth tax

California’s proposed Proposition 40, a one-time 5 percent tax on billionaires’ assets, has triggered a record wave of political spending. More than 70 current and former California billionaires have contributed a combined $612 million to state elections this year, with nearly half going to groups opposing the measure. At least 30 billionaires have put more than $293 million toward defeating it; most made their fortunes in technology, though donors also include business figures from other industries and across the political spectrum. Google co-founder Sergey Brin is the largest opponent-side donor, committing $102 million to Building a Better California. The other major share of billionaire spending came largely from wealth-tax supporter Tom Steyer, who financed his own unsuccessful gubernatorial campaign.

Opponents argue the tax threatens property rights, investment, jobs and California’s economic future, while supporters say it would help replace federal health-care funding cuts. The campaign has united Silicon Valley donors more effectively than previous political efforts, drawing in longtime megadonors and people with little or no history of political giving. Some billionaires have left or considered leaving California to avoid the tax, while others, including Anduril founder Palmer Luckey, say they will stay and fight it. Tech leaders describe the campaign as a catalyst for broader, longer-term political organizing to promote business-friendly policies. The scale is striking against the previous near-record: billionaires spent $147 million on California races and ballot measures in 2010.