openai.comarticle

Our approach to EU text provenance rules

OpenAI explains how it will meet the EU AI Act's machine-readable marking requirement for generated text. It uses textGrain, an invisible statistical watermark on word choices. API customers can opt in globally, ChatGPT and Codex output in the EU gets the watermark by default, and detector access is limited to approved researchers. The post gives detection numbers: about 80% at 200 tokens and 95% at 400 tokens at a 1% false-positive rate, falling to 66% and 17% when 10% and 25% of words are replaced with synonyms. It also lists what a watermark cannot show, such as human contribution, ownership, user identity, accuracy, or proof of human authorship, and places text provenance within a layered approach with C2PA Content Credentials and SynthID.