Bing separates AI-training and grounding preferences

What changed

The training preference can apply to a site or path through robots.txt, with a page-level override. Grounding is controlled at page level. Microsoft’s DisallowExtended option limits grounding to Microsoft-operated experiences and excludes its grounding services for third parties. These choices do not guarantee inclusion, traffic or payment.

The dates matter. Microsoft says it will start honouring the new preferences as pages are recrawled from 1 February 2027. Sites relying on NoArchive or NoCache should complete the specified transition before 1 March, when those older preferences stop being read for training and grounding. Eligible sites can record a temporary grounding transition preference in Bing Webmaster Tools from 15 December 2026.

Publishers should review the linked implementation guide and inventory existing directives before migrating. This is an announced transition, not confirmation that the new controls are already effective. Krishna Madhavan receives the signed original-announcement credit.

For a site owner, the two decisions should be recorded separately: whether content may train future generative models, and whether it may supply context to generated answers. A restriction on one use is not a substitute for a restriction on the other. Keep an inventory of which templates emit page-level preferences, which paths have site-level rules and who owns the transition. This makes it easier to spot conflicting settings and to explain a deliberate visibility trade-off without confusing it with removal from traditional search.