AI Matters
Why it matters
Anthropic adds invisible watermarks to text processed by Claude
Ars Technica Claude's new Scarlet Letter watermark is invisible—for now
Anthropic has introduced an invisible watermarking system that flags any text processed or edited by its Claude AI model.
Why it matters
Students and professionals using Claude to edit their writing may find their work flagged as AI-generated, even if they wrote the original text.
Latest brief · Aug 13, 2026