Question · California AI Transparency

Does California require AI training-data disclosure?

SB 942 requires large generative AI providers to embed hidden provenance disclosures in content their systems create, offer users a visible disclosure option, and run a free public detection tool.

AboutCalifornia AI Transparency
Legal forceBinding law
Applies from2 Aug 2026
Checked21 Oct 2026

01 / The answer

The short answer

Yes. AB 2013 (Chapter 817, Statutes of 2024) requires the developer of a generative AI system or service made publicly available to Californians, and released on or after 1 January 2022, to post documentation on its website about the data used to train it. The first posting was due on or before 1 January 2026, and the documentation must be posted again before each later release or substantial modification. It is a disclosure duty about training data, not a ban on using any data.
California AI Transparency · checked 21 Oct 2026

02 / The rule

What California AI Transparency requires

SB 942 requires large generative AI providers to embed hidden provenance disclosures in content their systems create, offer users a visible disclosure option, and run a free public detection tool. AB 853 moved the operative date to 2 August 2026, the same day EU AI Act Article 50 begins to apply.

  1. 01Embed a latent disclosure in covered content: provider name, system name and version, creation or alteration time, and a unique identifier.
  2. 02Make the latent disclosure detectable by the provider's own tool, consistent with industry standards, and permanent or extremely difficult to remove.
  3. 03Offer users the option of a clear, conspicuous manifest disclosure appropriate to the medium.
  4. 04Provide a free, publicly accessible detection tool with upload or URL input and an API, without outputting personal provenance data.

03 / Records

Records to keep

  1. 01Latent disclosure specification and per-release test results
  2. 02Logs showing the manifest-disclosure option was offered on each surface
  3. 03Detection tool uptime and API availability records
  4. 04Licensee monitoring records with discovery and revocation timestamps

Optional evidence · where Planisphere fits

Keep a record anyone can check

When your team meets a duty, Planisphere can seal the event it reports as a receipt.

01 · Your teamRecord the event

A disclosure shown, a review signed, a model change approved: the event your system reports.

02 · PlanisphereSeal it

The event becomes a sealed receipt, dated and attributed to whoever is signed in.

03 · AnyoneCheck it

Paste the receipt into Verify. No account or key.

A record supports your compliance evidence process. It is not a legal finding or a certification. Systems that call Planisphere's gate API can also hold or refuse an action before it runs.

SOURCES

Go back to the source

PRIMARY
PRIMARY
AB 853 (2025): amendments to the AI Transparency Act

California Legislative Information

SECONDARY
C2PA technical specification 2.1

Coalition for Content Provenance and Authenticity

RELATED

Related: California AI Transparency: the full guide · When does California SB 942 take effect? · What is California SB 53 frontier AI law? · Do CCPA ADMT rules require a risk assessment?