California's SB 1000 would label AI from every generator

California has a law that forces AI generators to watermark their image, video and audio output, and a bill on the governor's desk would widen it to every generator a Californian can reach. SB 1000 was enrolled and presented to Gov. Gavin Newsom at 3 p.m. on September 2, 2026, and there is no signature or veto on the record. California's constitution says a bill passed before September 1 and in the governor's possession on or after September 1 becomes a statute if it is not returned on or before September 30, and that is the deadline here.

Here is what the bill changes, from the enrolled text and the Legislative Counsel's Digest.

It deletes the size threshold. The California AI Transparency Act, which began operating on August 2, 2026, currently defines a "covered provider" as a person that creates, codes or otherwise produces a generative AI system with over 1,000,000 monthly visitors or users that is publicly accessible inside California. The digest says SB 1000 would delete that user threshold. Practically, that is the difference between regulating a dozen frontier labs and regulating every image, video and audio generator a Californian can open, including the small ones.

It renames the tool you use to check a file. Where the law requires a provider to make an "AI detection tool" available free of charge, SB 1000 substitutes "disclosure verification tool." The text sets out what the tool must do: let a user assess whether image, video or audio content was created or altered, except by a minor modification, by that provider's system, and output any system provenance data detected in the content.

It drops the optional visible label and keeps the hidden one. Existing law requires a provider to offer the user the option to include a manifest — that is, visible — disclosure in generated image, video or audio, and to include a latent, machine-readable disclosure in content its system creates. The bill deletes the requirement to offer the manifest disclosure. The reasoning is in the bill's own findings: conveying conflicting manifest and latent provenance information "is detrimental to trust in both the provenance of content and the authenticity of any person, entity, or institution conveyed in that content." Findings elsewhere in the bill say provenance technology is still developing, that information should be resilient to common transformations "to the extent technically feasible over time," and that legislation needs to stay adaptive and standards-agnostic.

It names the two exemptions. The chapter does not apply to products or services that offer exclusively non-user-generated videogames, and — from the bill's amendment to the exemptions section — it does not apply before January 1, 2029 to a generative AI system designed to primarily function as assistive technology. The digest adds that a provider would be prohibited from falsely representing that its system is designed to primarily function as assistive technology, and would face a civil action for doing so.

It starts the moment it is signed. SB 1000 declares itself an urgency statute, to take effect immediately. The votes were not close: the Senate passed it 33-1 on May 19, 2026, the Assembly passed it 72-0 with the urgency clause adopted on August 25, and the Senate concurred 39-0 on August 27.

What it does not do is tell you what to do with a clip you have already made. The duties run to the provider — the system that generated the content — not to the person who posted it, and the act's changes here are about which providers are covered, which disclosure is mandatory and what a verification tool must return. If you build on a covered system, the part that touches you is the effect on your tool: expect the labelling behaviour to be mandatory rather than optional, and expect the checker to be free and documented.

One caution on the date. The leginfo history page can lag the governor's office by a day or two. If you are publishing anything about the signing, check gov.ca.gov first, because the deadline is days away.

If you want to read the thing yourself, the enrolled text and the digest are both at leginfo.legislature.ca.gov, and the compliance questions you actually have — which of my tools is a covered provider, and what my checker has to return — are answered in sections 22757.1 through 22757.3.