Landmark win for AI safety: Gov. Newsom signs Transparency in Frontier AI Act into law

California Gov. Gavin Newsom, above, signed SB 53 into law earlier today. “California has proven that we can establish regulations to protect our communities while also ensuring that the growing AI industry continues to thrive,” he said.

Sept. 29, 2025 — In a historic step for AI safety, California Gov. Gavin Newsom today signed into law Senate Bill 53, the Transparency in Frontier Artificial Intelligence Act (TFAIA), authored by state Sen. Scott Wiener (D-San Francisco).

The new law is designed to enhance online safety by installing commonsense guardrails on the development of frontier artificial intelligence models, helping build public trust while also continuing to spur innovation in these new technologies.

The new law builds on recommendations from California’s first-in-the-nation report, called for by Governor Newsom and published earlier this year — and helps advance California’s position as a national leader in responsible and ethical AI, the world’s fourth-largest economy, the birthplace of new technology, and the top pipeline for tech talent.

Gov. Newsom: We can protect communities and AI industry

At the bill signing, Gov. Newsom said: “California has proven that we can establish regulations to protect our communities while also ensuring that the growing AI industry continues to thrive. This legislation strikes that balance.”

“AI is the new frontier in innovation,” he added, “and California is not only here for it—but stands strong as a national leader by enacting the first-in-the-nation frontier AI safety legislation that builds public trust as this emerging technology rapidly evolves.”

transparency coalition: ‘huge step forward’

Jai Jaisimha, co-founder of the Transparency Coalition, praised Gov. Newsom’s bold step in protecting both communities and innovation.

“This is an important development since it shows that it is possible to be both pro-innovation and pro-safety,” said Jaisimha. “SB 53 calls for greater transparency in the development of AI models and also provides whistleblower protections for critical and high risk models.”

“While the bill does have some shortcomings,” Jaisimha added, “it’s a huge step forward in the AI regulatory landscape in California that will also have global implications.”

Sen. Weiner’s follow-up to 1047

SB 53 was sponsored by Sen. Scott Wiener (D-San Francisco), the author of last year’s ill-fated SB 1047. The ambitious 2024 bill was the focus of much controversy, as it gained approval in the California legislature but fell to Gov. Newsom’s veto last September.

This year’s bill was widely seen as Sen. Wiener’s effort to strike a balance between the safety measures proposed in 1047 and Gov. Newsom’s earlier objections. Wiener achieved that balance by incorporating many of the suggestions put forth by Newsom’s Joint California AI Policy Working Group.

“With a technology as transformative as AI, we have a responsibility to support that innovation while putting in place commonsense guardrails to understand and reduce risk,” said Sen. Wiener. “With this law, California is stepping up, once again, as a global leader on both technology innovation and safety. I’m grateful to the Governor for his leadership in convening the Joint California AI Policy Working Group, working with us to refine the legislation, and now signing it into law. His Administration’s partnership helped this groundbreaking legislation promote innovation and establish guardrails for trust, fairness, and accountability in the most remarkable new technology in many years.”