How Claude's Text Watermarking Works
Anthropic explains the implementation of text watermarking for Claude, a technique that embeds an imperceptible pattern in generated text to help identify AI-generated content, complying with the EU AI Act. The watermark doesn't affect output quality, cost, or speed, and can't be traced to individual users. It leverages low-stakes word choices to create a detectable pattern, but has limitations with short texts, factual passages, and code.
Watermarking uses low-stakes choices like these—which occur many times over a piece of generated text—to leave a pattern in Claude’s responses.