OpenAI will start watermarking ChatGPT’s text in the EU

OpenAI announced it will implement an invisible watermark on text generated by ChatGPT and Codex within the European Union. This measure is intended to comply with the EU AI Act. However, OpenAI's tests indicate that the watermark can be removed through editing; for example, replacing 10% of words with synonyms reduced detection rates significantly. The company also noted that short passages, mathematical answers, and translated texts are more challenging to detect.

This report details OpenAI's first move to watermark AI-generated text in the EU, unlike other regions, but also reveals the method's limitations against simple editing.