Palmer Luckey, Jensen Huang, Elon Musk, and more have commented on California's billionaire tax proposal.

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Some of the biggest names in business are speaking up about California's billionaire tax proposal. Others are physically relocating.The measure proposes a one-time 5% tax on California residents with assets exceeding $1 billion. The measure was certified for the November 2026 ballot on June 25 after receiving enough valid signatures.If the proposal passes, the tax would apply retroactively to all California residents as of January 1.Proposed by the Service Employees International Union-United Healthcare Workers West labor union, the bill attempts to fill a projected multibillion-dollar state budget deficit.California is home to some of the biggest companies — in both value and prestige — in the US. The state boasts Hollywood and Silicon Valley, although some of the industries' key players have relocated.In a letter to Gov. Gavin Newsom obtained by Business Insider, attorney Alex Spiro wrote that his clients would "permanently relocate" if the tax becomes law. Spiro has previously represented billionaires and celebrities.Newsom said he opposed the one-time wealth tax for the state but advocated a nationwide billionaire tax instead.Here's how several business leaders and politicians have reacted to the tax proposal: