Have any court challenges been filed against California's exit tax or residency rules recently?

1. What’s actually been proposed — and what died in committee

Legislative proposals that would have created wealth‑ or exit‑tax-like obligations, including the high‑profile “billionaire tax” (Assembly Bill 259) and related measures, failed to advance and were reported as dying in committee in early 2024, meaning no statutory exit tax was enacted for courts to review on the merits ^{[1] [2]}.

2. Litigation that did happen: the pre‑election fight over a broad anti‑tax initiative

The most significant court action in the period covered by these sources was the California Supreme Court’s decision to block a business‑backed anti‑tax ballot initiative, the Taxpayer Protection and Government Accountability Act (TPA), from the November 2024 ballot after a full hearing — an extraordinary pre‑election review prompted by concerns including retroactive provisions — a case reported by CalMatters and legal commentators ^{[3] [4]}.

3. Who sued whom — competing narratives and political stakes

Reporting and advocacy outlets frame the TPA fight differently: Reform California and allied tax‑cut groups emphasize opposition to taxes and assert that Governor Newsom and state Democrats sued to keep the initiative off the ballot ^[5], while legal reporting and law‑firm summaries note the California Supreme Court’s unanimous decision to bar the measure after hearing constitutional challenges brought in the months before the election, a move characterized by some as a win for state and local governments and by others as an interference in the ballot initiative process ^{[3] [4]}.

4. Predicting litigation against an exit tax that never materialized

Legal scholars and tax practitioners have long predicted that a robust exit tax would face high‑stakes constitutional challenges — on due process, takings, interstate‑travel and equal‑protection grounds — and analyses have concluded courts might invalidate aggressive exit‑tax schemes if enacted, but those discussions remain hypothetical because the bills stalled and there is no court record of a direct challenge to an enacted exit tax in the sources provided ^{[6] [7]}.

5. Residency enforcement vs. exit tax: two separate fights

Several commentators stress that California’s bigger, ongoing enforcement problem is residency determination and the Franchise Tax Board’s long reach, which creates real disputes over who remains taxable after moving out of state; those residency enforcement disputes do produce appeals and litigation in tax courts and administrative venues, but the present sources do not document a recent, high‑profile court challenge specifically overturning new residency rules or an exit tax because the latter were not enacted ^[1].

6. Hidden agendas and the information environment

Advocacy groups on both sides have incentives to conflate proposals, ballot measures and litigation to shape public opinion: anti‑tax groups amplify the threat of an exit tax and promise more litigation ^[5], while government‑side summaries and court decisions emphasize constitutional limits and governance needs ^[4]; readers should note that much reporting mixes prospective legal analysis with political messaging about who benefits from blocking or advancing these measures ^{[6] [4]}.

7. Bottom line and limits of available reporting

Based on the reporting supplied, there is no record of a recent, successful court challenge to an enacted California exit tax or newly created residency rule because no such law was enacted — instead, the recent, notable court action was the California Supreme Court’s blocking of an anti‑tax ballot initiative in mid‑2024, and separate commentary predicts that any future exit tax would face serious litigation ^{[1] [2] [3] [6] [7]}. This assessment is limited to the provided sources; if a complaint or suit were filed in a venue not covered here after those reports, it is not reflected in this account.