Key point: California expands the scope of the California AI Transparency Act by adding compliance obligations and extends the operative date to August 2, 2026.
On October 13, 2025, California Governor Gavin Newsom signed AB 853 — amendments to the California AI Transparency Act (CAITA) — into law. AB 853 expands the responsibilities previously required of creators of generative artificial intelligence (GenAI) systems specifically with respect to large online platforms, entities that distribute the source codes for, and products of, GenAI systems, and entities that manufacture capture devices. The operative date is also extended from January 1, 2026, to August 2, 2026 to align with the EU AI Act although new provisions have delayed effective dates. The amendments expanding CAITA’s scope reflect California’s active stance in developing regulations for emerging technologies.
Below, we provide a brief background and summary of some of the law’s more notable provisions.
Background
California lawmakers passed CAITA during the 2024 legislative session through SB 942. At its core, the law is about creating tools to detect AI deepfakes. The bill sponsor’s statement explained: “One of the most concerning aspects of unregulated AI models is their potential to produce ‘deepfake’ content, such as manipulated images and videos, which can be used to deceive or manipulate individuals and society at large.” SB 942 passed with strong bipartisan support and was signed into law by r Newsom on September 19, 2024.
As originally enacted, CAITA creates obligations for “covered providers,” which are defined as persons that create, code, or otherwise produce a GenAI system that has more than one million monthly visitors or users and is publicly accessible within California. Under CAITA, covered providers are required to make a free and public AI detection tool, offer the user an option of including a manifest disclosure in certain GenAI created content (e.g., a visible label or watermark), include a latent disclosure in certain GenAI created content, and add contractual obligations to licensees of their GenAI system to ensure transparency. Notably, while the law’s definition of GenAI system refers to the creation of text content, the word “text” was removed from the substantive provisions of the law such that the obligations only apply to image, video, or audio content. This is an important qualification in understanding the law’s scope.
AB 853 amends and builds on CAITA to apply new requirements to large online platforms (e.g., Instagram and X), GenAI hosting platforms, and capture device manufacturers (e.g., cameras and smartphones), in addition to the covered providers. With respect to large online platforms, the bill analysis explains that most individuals engage with digital content through these platforms, therefore “it is both practical and impactful to place a duty on them to help users determine the authenticity of the content they encounter.” The bill analysis further explains that capture device manufacturers produce significantly less content but, given that there are a limited number of manufacturers, “enforcement becomes more feasible.”
Large Online Platforms
Under AB 853, a “large online platform” is defined as a public-facing social media platform, file-sharing platform, mass messaging platform, or stand-alone search engine that distributes content to users who did not create or collaborate in creating the content that exceeded two million unique monthly users during the preceding 12 months, excluding broadband internet access services and telecommunications services. Beginning January 1, 2027, large online platforms are required to (1) detect whether certain provenance data is in any content they distribute, (2) provide a user interface to disclose the availability of system provenance data, indicating whether content was generated or substantially altered by GenAI systems or captured by capture devices, and provide certain information on the content’s authenticity and modification history, and (3) allow users to inspect system provenance data in an easily accessible manner.
GenAI Hosting Platforms
AB 853 defines a “GenAI hosting platform” as an internet website or application that makes available for download the source code or model weights of a GenAI system by a California resident. Beginning January 1, 2027, a GenAI hosting platform must not knowingly make available a GenAI system unless it provides users with the option to include a manifest disclosure that the content was AI-generated; and it includes a latent disclosure in AI-generated content, conveying certain information of the GenAI system’s CAITA compliance.
Capture Device Manufacturers
AB 853 also provides regulations on “capture device manufacturers,” defined as entities that produce devices capable of recording photographs, audio, or video content, with built-in cameras or microphones, and voice recorders for sale in California. For any capture device produced for sale in California from January 1, 2028, a capture device manufacturer must (1) provide users with the option to include a latent disclosure about the capture device and the time and date of the alteration/creation in content captured by the capture device, and (2) embed latent disclosures in content captured by the device by default.