Anthropic will embed invisible watermarks in text generated by new Claude models and attach signed provenance metadata to supported files, implementing commitments under the European Union’s new transparency requirements for AI-generated content. The policy covers Claude models launched on or after August 2, 2026. Although prompted by Article 50 of the EU AI Act, marking will apply wherever supported Claude models are offered worldwide. Anthropic has signed the Article 50(2) Code of Practice on Transparency of AI-Generated Content. The plan uses two forms of machine-readable marking, one embedded directly in generated text and another attached to files. Outputs will be marked across Anthropic’s products, including the Claude Platform API, Claude, Claude Code, Claude Cowork and Claude Tag. Embedded watermarks will also apply when supported models are accessed through AWS, Google Cloud or Microsoft Foundry. Signed provenance metadata may be unavailable through some cloud platforms, products, features or file types. The watermark remains part of the text when copied and pasted and may survive some subsequent editing. Supported files, including SVG, PNG and JPG formats, will receive digitally signed provenance metadata based on the C2PA open standard. A valid label signals that Claude processed the file and can indicate whether it has been altered, but does not prove Claude originated everything within it. A detected mark indicates Claude may have processed content, not its complete history, and failing to detect a mark does not demonstrate content was produced without AI. A mark may