On September 29, 2025 - exactly one year after vetoing the more sweeping SB 1047 - Governor Gavin Newsom signed Senate Bill 53, the Transparency in Frontier Artificial Intelligence Act (TFAIA), also authored by Senator Scott Wiener. The official announcement from the Governor’s office described it as a law to advance “California’s world-leading artificial intelligence industry” while establishing guardrails for the largest model developers.
The law centers on disclosure rather than the pre-deployment safety mandates of the vetoed bill. According to the Governor’s office, it requires “large frontier developers” to “publicly publish a framework on its website describing how the company has incorporated national standards, international standards, and industry-consensus best practices” into how they develop frontier models. It also “protects whistleblowers who disclose significant health and safety risks posed by frontier models” and creates civil penalties for noncompliance enforceable by the Attorney General. A separate provision establishes “CalCompute,” described as “a new consortium within the Government Operations Agency to develop a framework for creating a public computing cluster” to support safe and ethical AI development.
Newsom framed the signing as proof of a workable middle path, saying: “California has proven that we can establish regulations to protect our communities while also ensuring that the growing AI industry continues to thrive.” The TFAIA is widely described as the first US state statute aimed specifically at the developers of frontier foundation models.
Why business readers should care: SB 53 marks where US state AI regulation actually landed after the SB 1047 fight - on transparency and whistleblower protection rather than mandatory safety testing or a licensing regime. For frontier developers it created concrete, published-on-the-website obligations enforceable by a state attorney general, and it positioned California as a de facto national regulator in the absence of comprehensive federal AI legislation.