Anthropic said Claude outputs will carry machine-readable marks after it signed the EU AI Act Article 50(2) Code of Practice on AI-generated content transparency, The Hindu reported. New EU-facing Claude models from August 2 must support the marks at launch, with older models on a transition path. Text gets an imperceptible watermark that survives copy, paste, and light edits, while supported image files can carry signed provenance across Claude apps and major clouds. Why it matters: provenance is becoming a product default under European rules. Caveat: marks can miss after heavy edits and do not prove Claude was the sole author.