One of the most conspicuous economic disputes of this autumn is flaring up in California.
Six laureates of the Nobel Prize in Economics — Daron Acemoglu, Abhijit Banerjee, Peter Diamond, Esther Duflo, Paul Krugman and Joseph Stiglitz — have come out in support of Proposition 40, an initiative for a one-time tax on the state's largest fortunes.
The measure in question is a tax of up to 5% on the wealth of people whose taxable assets exceed $1 billion and who were residents of California on 1 January 2026. Real estate, retirement accounts and certain other assets are not included in the calculation.
The initiative's main goal is healthcare. 90% of the funds raised are to go to medical programs, and the remaining 10% to food assistance, educational programs and the administration of the tax itself. According to estimates by the authorities, this could mean tens of billions of dollars in additional revenue, distributed over several years.
Why has the issue become so conspicuous precisely now? California remains home to several hundred billionaires, a significant portion of whom are connected to the technology sector. The combined wealth of California's billionaires is estimated at roughly $2,3 trillion.
In recent years their wealth has grown sharply, especially amid the artificial intelligence boom. At the same time, supporters of Proposition 40 point out that the share of taxes relative to the increase in the fortunes of the largest owners of capital has remained comparatively low.
This is precisely what became one of the main arguments in favour of a one-time tax on ultra-large fortunes.
But the dispute is far from one-sided.
Opponents of Proposition 40 warn that the tax could push wealthy residents to move away, reduce the state's future tax revenues and create difficulties in valuing private companies, works of art, intellectual property and other assets that cannot simply be looked up in a stock market terminal.
Supporters, by contrast, believe that the scale of accumulated wealth is so great that a one-time levy will not destroy the innovative economy, but can give healthcare a significant financial resource.
The Nobel laureates went even further: they see the vote in California as a possible experiment that other states and countries will follow closely. If such a model proves politically and economically viable, the debate about taxes on the ultra-wealthy could gain new momentum far beyond California.
The vote will take place on 3 November 2026.
For now, Proposition 40 has a small lead in the polls: about 52% of likely voters are ready to support the initiative, about 46% are against it. But there is still time before the vote, so the outcome remains open.
That is precisely why the November vote will be of interest not only to California.
The question here is already far broader than a single tax: how far society is prepared to go in redistributing ultra-large fortunes — and whether it can do so while preserving investment, innovation and the region's attractiveness for business.
The answer will now be given by the voters themselves.
