California voters face a closely contested November 2026 ballot measure that would amend the state constitution to bar new taxes on personal property ownership—including retirement accounts, financial assets, and business interests—while prohibiting most retroactive taxes based on prior residency or conduct. The measure emerged as a direct counter to a competing billionaire tax initiative that applies retroactively to net worth above $1 billion using a January 1, 2026 residency cutoff, creating overlapping provisions that trigger competing-measures rules. Trader sentiment remains balanced near 50 percent because both proposals qualified recently through signature drives, fiscal impact estimates highlight potential revenue trade-offs, and campaigns are only beginning to frame voter priorities around tax fairness, emergency exceptions, and future legislative flexibility ahead of the November election.