TL;DRNew Claude models launched from August 2 will embed invisible watermarks in generated text.The marks will apply worldwide, can travel with copied text, and can survive some editing.Anthropic says existing Claude models will also gain marking support during the EU AI Act’s transition period.Anthropic is adding invisible watermarks to text generated by the latest Claude models, giving AI-written content a hidden signal that can follow it even after it’s copied out of the chatbot.The change comes as Anthropic signs the EU AI Act’s Article 50(2) Code of Practice on Transparency of AI-Generated Content. In an update published on its privacy and legal support page, Anthropic says that new Claude models launched from August 2, 2026, will support machine-readable marking from day one. Despite the EU regulation prompting the move, the markings will apply worldwide wherever Claude is offered.