We’ve written an FAQ to answer some of the questions we've received about watermarking. In summary…

TL;DR - Anthropic will watermark text from future Claude models to comply with the EU AI Act. The watermark is designed to indicate likely Claude involvement without visibly altering text, reducing quality, or increasing token costs.

• Other major model developers signed the same Code of Practice and plan to implement watermarking.
• Readers should not be able to distinguish watermarked from unwatermarked text.
• The method adds no hidden characters or extra tokens.
• Watermarks cannot be traced to a specific user, organization, or conversation.