California SB 53: Transparency in Frontier Artificial Intelligence Act
California Legislature; signed by Governor Gavin Newsom · 2025-09-29 (signed); 2026-01-01 (effective)
California now requires the largest AI developers to publish their safety plans and report serious incidents, and protects employees who raise concerns. The federal government is trying to override it.
What it calls for
- Transparency
- Safety evaluations
- Worker protection
- Liability
Scope
Applies to developers training >10^26 FLOP models with >$500M revenue; whistleblower protections and incident reporting to Cal OES
What actually happened
The first US frontier-AI law, after SB 1047 was vetoed in 2024; it requires published frontier frameworks, transparency reports, and 15-day critical-incident reporting (https://en.wikipedia.org/wiki/Transparency_in_Frontier_Artificial_Intelligence_Act). It is a target of the Dec 2025 federal preemption order and DOJ litigation task force (https://www.lawfaremedia.org/article/trump-signs-executive-order-to-preempt-state-ai-laws). OpenAI subpoenaed SB 53 advocates Encode during the legislative fight (https://fortune.com/2025/10/10/a-3-person-policy-non-profit-that-worked-on-californias-ai-safety-law-is-publicly-accusing-openai-of-intimidation-tactics). Looked for: first enforcement actions or incident filings - none public yet.