Anthropic, the creators of Claude, announced Tuesday that it is working on mechanisms to ensure every generated text carries embedded watermarks and generated files include digital signed provenance metadata worldwide.
Anthropic said that the rollout of watermarked AI generated texts and signed provenance metadata files are in accordance with European Union AI Act’s Article 50(2) Code of Practice on Transparency of AI-Generated Content, under which all Claude models launched on or after August 2, 2026 will have mandatory watermarking.
Anthropic also said that they are currently working on adding marking support to the rest of the Claude models released prior to August 2.
The AI startup informed that Claude markings will feature across models include Claude Platform (API), Claude, Claude Code, Claude Cowork, and Claude Tag.
“When a supported Claude model generates text, it weaves an imperceptible watermark directly into the text itself. You won’t see it, and it doesn’t change the meaning, quality, or readability of Claude’s response. Because the watermark is part of the text, it will travel with the text when it’s copied and pasted elsewhere, and may persist through some editing. Watermarking will be applied at the model level, which means it will be present no matter which Claude product or surface the text comes from,.” wrote Anthropic in a post.
However, Anthropic has not detailed upon the watermarking method to be used, the minimum text length to be considered for a reliable result, and parameters for false positive and false negative rates in detection.
Anthropic has also clarified that mere detection mark does not conclusively imply that a certain text or image was generated by Claude.
“A detected mark provides a signal that content was processed by Claude, but is not fully conclusive. Detecting a Claude mark tells you that the content may have been processed by Claude. It does not, on its own, confirm the full provenance of the content. For example, Claude may not be the original author. People often use Claude to proofread, translate, summarize, or convert files. The output can carry a Claude mark even if the underlying ideas, text, or data originated from another source. Similarly, the content may have changed after Claude processed it. Marked content may be modified, excerpted, or combined with other material after Claude processed it.”
