C2PA defines a signed manifest that travels with an image, video, audio or document file and records its origin and edit history, including whether an AI system generated or processed it. Camera makers, Adobe and the major AI labs use it; Anthropic attaches Content Credentials to image and file outputs from Claude.
Because the credential lives in file metadata rather than in the content, it is honest and cheap but fragile: screenshots, format conversions and copy-pasted text drop it. That is why text outputs use a statistical watermark instead.
