Check if a file was made with Claude

To determine if a file was created using Claude, one must utilize a specialized tool that checks the file's content credential. This credential indicates whether Claude was involved in producing the file's content, although it does not provide details about the user involved. The content credential is embedded within the file's metadata as a cryptographically signed note, visible only through C2PA-compliant tools, similar to those used by camera manufacturers and photo-editing software.

When Claude processes a file type like .png, .jpg, or .svg, this credential is added. If such a credential referencing Claude is detected, it confirms that the file was made or processed with Claude. Other model providers, such as OpenAI, Google DeepMind, and Gemini, also offer similar verification tools. Furthermore, for detecting watermarks embedded in text, a Detection API is available in private preview, subject to EU law compliance.