xAI will add an invisible watermark to Grok API text by default from Nov 7, citing the EU AI Act
xAI's docs (branded SpaceXSI) say text from grok-4.7, 4.6, 4.5, 4.3 and three grok-4.20 models will carry an invisible watermark by default from Nov 7, including structured outputs and tool-call arguments. It shapes token choice, adds no characters and is flagged by an x-watermark: true header. Admins can opt out per model only if a legal exception applies.
Why it matters
A leading lab is turning on text watermarks by default to meet the EU AI Act's marking duty, a sign watermarking is becoming a baseline for offering models in the EU.
Sources2
Written by dalao.ai: the title, summary and why it matters are our own words. The original reports are the record; their publishers keep authorship.