TL;DR
The empirical question is getting its first hard answers, and they cut both ways: California's residency thread resolved with six named billionaires departing before the Jan 1 snapshot — vindicating the exit-anticipation critique — while Washington's official forecasters revised their income-tax revenue up 15% on income growth alone, with the migration question left unmodeled. Hungary locked in a January 1, 2027 start date, making a low-capacity, high-mobility EU state the cleanest live test of whether implementation can survive where Germany, Sweden, and France couldn't.
California: the exit record is now a list of names, not a theory
The residency question that underpinned the entire $100B-vs-$40B revenue dispute has been answered with real-estate receipts and corporate filings, not modeling assumptions.
"I fled socialism with my family in 1979 and know the devastating, oppressive society it created in the Soviet Union." — Sergey Brin, quoted in 24/7 Wall St.'s accounting of named departures
Bloomberg's reporting documents at least six billionaires — Page, Brin, Thiel, Hankey, Kalanick, Spielberg — who publicly cut California ties before the snapshot: Page bought two Miami waterfront mansions for a combined $173M and re-domiciled his family office to Delaware/Florida; Thiel shifted his family investment firm to Miami in late December 2025 state-level-wealth-tax-proposals-california-2026-initiative+2. The Hoover Institution's person-by-person analysis attributes $536B — nearly 30% of the base — to departures before the initiative even qualified, and $26.7B of the reduction to Page and Brin alone. The named counterpoint is Jensen Huang, facing a potential $8B bill: "The fact that I can afford to pay $8 billion in taxes over five years is a privilege."
The administrability wrinkle that could outlast the vote: the valuation approach reaches control rights, not just net worth — DoorDash's Tony Xu holds 57.6% of voting rights on 2.6% of equity, and his computed bill exceeds the value of shares he actually owns state-level-wealth-tax-proposals-california-2026-initiative+2. That's a litigation magnet if the measure passes, and a design lesson regardless.
What to watch: The Nov 3 vote against Prop 41 and 42 — either countermeasure out-polling Prop 40 voids the tax, and the anti-retroactivity measure targets the snapshot device that was supposed to neutralize exit.
Washington: the forecasters' revision is the most instructive scoring event of the season
Washington's official score moved up — and the fight over why is a template for every future wealth-tax estimate.
"We do not have any actual collections to inform this question, so we estimate the impact using a variety of data sources that are in turn influenced by the most recent economic forecast." — Washington State Standard, quoting DOR
The September 25 ERFC Revenue Review adopted the upward revision: the Individual Income Tax forecast rose $2.382B for the 2029-31 biennium, on top of DOR's August move to $3.1B first-year and roughly 25,000 paying households — 4,000 of them households that merely crossed the $1M threshold as income grew washington-state-wealth-tax-study-and-constitutional-constraints+1. The contestable assumption sits in plain sight: zero behavioral response. Initiative sponsor Brian Heywood's rebuttal — "They think nobody is going to leave because of the tax. They're wrong" — is the same migration critique that drove the California exits, here lodged against a scoring agency that concedes it cannot measure the question until collections exist.
What to watch: The December DOR workgroup reports on residency and implementation — the first administrative read on whether the base holds, ahead of the Culliton v. Chase litigation that remains open.
Hungary: the reversal wave gets a date and a rate hint
Europe's repeal era produced its first genuine counter-current with real legislative momentum behind it.
"Péter Magyar announced that the wealth tax, to be introduced from 1 January 2027, will be implemented under stricter conditions than those originally pledged. He said it was possible that above a certain threshold — 500 billion forints — the tax rate would be higher than one percent." — The Budapest Times
The timing is locked and a progressive surcharge above 1% is floated, but the bill — asset scope, official scoring — remains unpublished, with Finance Minister Kármán cast as the detail man hungary-wealth-tax-proposal-2026-and-european-reversal-wave. The fiscal motive is explicit: Magyar describes inherited books where "a deficit of 8 to 9 percent [was] misrepresented as 3 to 4 percent" — this is revenue repair at least as much as inequality policy, the same deficit-era logic behind Spain's solidarity tax. The KPMG caveat stands: actual revenue is uncertain because wealthy Hungarians can use tax planning, in a country inside the EU's single market where relocation is a short drive.
What to watch: The formal bill's rate schedule and asset scope — the cleanest test of whether a low-capacity, high-mobility EU state can administer what high-capacity states repealed.
What surprised us
- The exit story resolved for the skeptics, but with a twist. The six named departures and the ~30% base erosion confirm anticipatory flight is real and documentable — yet Huang's stated willingness to pay $8B shows exit is a choice, not a law of nature, and the tax hasn't even passed state-level-wealth-tax-proposals-california-2026-initiative
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- Washington's revenue went the "wrong" direction. The canonical wealth-tax failure mode is underdelivery, yet the first official forecast revision was up 15% on income growth — the migration response is the unmodeled variable, and both sides agree nobody can measure it yet washington-state-wealth-tax-study-and-constitutional-constraints
+1.
- Hungary's tax is a budget story, not an ideology story. A misreported deficit, not a Tisza Párt social-democratic turn, is driving the reversal wave's flagship — which means its fate will hinge on collections, the one variable the repeals always lacked hungary-wealth-tax-proposal-2026-and-european-reversal-wave
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