California's AI Transparency Act became operative on 2 August 2026 for generative systems with more than one million monthly users that are publicly available in the state. Covered providers must ship a free detection tool, offer a hard-to-remove manifest disclosure on AI image, video, and audio, and embed latent provenance naming the system and creation time. Text-only outputs are outside this first wave. Penalties can reach $5,000 per violation per day, enforced by the state rather than private suits. Caveat: hosting platforms and large social services face later 2027 duties, and pending bills could still rewrite who is covered.