Governor Gavin Newsom’s October 9 endorsement of Proposition 42 has strengthened trader support by framing the measure as essential protection for retirement accounts and personal savings against the competing billionaire wealth tax on the same November 2026 ballot. The initiative would amend the state constitution to bar new taxes on personal property ownership enacted after January 1, 2026, and prohibit most retroactive taxes tied to prior residency or conduct, with a narrow emergency exception. Backed by major donors including Sergey Brin, it is structured so that whichever of the conflicting measures receives more votes prevails. Recent polling showing limited majority support for the wealth tax has further aligned trader consensus with passage of the prohibition measure.