Anthropic Implements Claude Text Watermarking

Anthropic has begun embedding imperceptible, machine-readable watermarks into text generated or processed by its Claude AI models. This update applies to all models launched on or after August 2, 2026, to comply with transparency requirements under the European Union AI Act. The watermarks are designed to persist through copy-pasting and some forms of editing.

The company plans to release a free API allowing users and third parties to verify the presence of these watermarks.