California tech tycoons have poured upwards of $356 million into political action committees to defeat Proposition 40, transforming a union-sponsored initiative into what analysts predict will be the costliest ballot measure fight in history. The measure asks California voters to approve a one-time 5% tax on state residents who are billionaires as of January 1, 2026. If passed, the levy would raise billions to shore up state healthcare services, alongside selected food assistance and education programs.
The proposal originated as a countermeasure drafted by the healthcare union SEIU-United Healthcare Workers West (SEIU-UHW) following federal budget legislation. Signed by Donald Trump, the One Big Beautiful Bill Act mandated a trillion dollars in reductions to Medicaid, the Affordable Care Act, and related programs over the next decade. Union president Dave Regan argued that without alternative revenue, the federal cuts taking effect in January could leave more than 3.4 million Californians, including millions of children, without health coverage.
Silicon Valley elites have treated the measure as an existential threat, escalating their counteroffensive in the final weeks before the midterm vote. Campaign filings show opposition committees spent over $42.8 million in the first two weeks of October alone—exceeding $2.5 million a day on television advertisements, consultants, and political lobbying. Tech leaders including cryptocurrency investor Chris Larsen and Google co-founder Sergey Brin mobilized to defeat the tax, with Brin reportedly confronting Governor Gavin Newsom directly to warn that the levy would compel wealthy entrepreneurs to flee the state.
The pro-tax campaign has operated with considerably fewer financial resources, relying instead on viral social media outreach, celebrity endorsements, and rallies led by prominent progressives, including Senator Bernie Sanders. Beyond California's borders, the contest is being closely watched across the country. Campaign analysts observe that tech donors are spending aggressively partly out of fear that a successful ballot in California could inspire similar wealth-tax initiatives in other states, turning the local referendum into a high-stakes test of policies aimed at addressing economic inequality.