California has enacted the most comprehensive state-level AI legislative package, covering frontier AI transparency, content provenance, election deepfakes, and AI companion chatbot regulation. Key statutes include SB 53 (Frontier AI Transparency Act), SB 942 (provenance), SB 243 (companion chatbots), SB 926 / 981 (NCII), and AB 2655 / 2839 / 2905 (elections).

• SB 53 (Frontier AI Transparency Act): risk disclosure and incident reporting for frontier AI developers above $500M revenue
• SB 942 (provenance), SB 243 (companion chatbots), SB 926 / 981 (AI-generated sexually explicit content with notice-and-removal)
• AB 2655 / 2839 / 2905 (political deepfake disclaimers, watermarking on campaign materials, expanded enforcement)

• Frontier developer transparency reports and whistleblower protections (SB 53)
• Mandatory AI labels and provenance metadata; companion chatbots must disclose non-human status
• Civil and criminal penalties varying by statute, with private rights of action in several
• AB 2655 partially struck down August 2025 on Section 230 / First Amendment grounds; other provisions remain in force