OpenAI adds text watermarking for EU AI Act compliance, but technique has limitations
OpenAI has begun offering API customers the option to watermark text output from certain models to comply with the European Union's AI Act, and plans to apply the watermarking to ChatGPT and Codex output in the EU in the coming weeks. The technique, called textGrain, adds an invisible statistical signal to word choices, but tests show it can be defeated by simple synonym substitution, and detection rates drop significantly on shorter passages.
