Proposition 42, a November 2026 constitutional amendment on the California ballot, would bar new taxes on personal property ownership such as investments, retirement accounts, and business interests while limiting retroactive levies tied to pre-enactment residency or conduct. Trader sentiment reflects a near-even split because the measure directly counters a competing billionaire wealth tax initiative that relies on retroactive residency rules for enforcement, pitting revenue-focused advocates against those prioritizing protections for unrealized gains and asset mobility. Campaign funding from high-net-worth backers has advanced the prohibition effort, yet broader voter support for public services and education funding creates counter-pressure, with historical patterns showing California voters often split on tax-related ballot measures. Developments that could shift the balance include shifts in campaign spending and advertising intensity, new polling on wealth taxation preferences, legal rulings testing the retroactive elements of related proposals, or economic indicators influencing views on state revenue needs ahead of the November vote.