xAI has not signed the EU Transparency Guidelines, but its Grok API will add text watermarks by default globally.

Beating AI News (Dongcha) reports: xAI has updated its developer documentation, announcing that starting November 7, it will add invisible text watermarks by default to API outputs for the Grok 4.7, 4.6, 4.5, 4.3 models and three Grok 4.20 variants. The measure covers not only EU but also global and regional APIs, with even structured outputs and tool call parameters marked. It remains unclear if the watermark will also be enabled for Grok’s web version and X’s built-in chat feature. The watermark works by slightly adjusting word selection probabilities during text generation, leaving identifiable statistical patterns in the generated text. Direct copy-pasting will not remove the watermark, while shortening text or extensive rewriting will reduce detection reliability. The move stems from transparency requirements under the EU AI Act, whose relevant provisions took effect on August 2. While xAI has not signed the EU’s voluntary transparency guidelines, it is still required to comply with applicable legal obligations. Developer teams can disable watermarks per model, but must confirm eligibility for relevant legal exemptions and bear full responsibility for marking and disclosure. Google implemented SynthID text watermarks for Gemini as early as 2024, and Anthropic began rolling out watermarks globally for its new Claude models in August this year. OpenAI announced in October that it would gradually add watermarks to ChatGPT and Codex for EU regions, while allowing global API users to enable the feature voluntarily, with it remaining disabled by default.