# Shared AI training preference for websites

> A proposed shared robots.txt training signal.

By BIGCHANGE.AI Editorial

Published: 2026-10-30T23:46:38.347Z
Updated: 2026-10-30T23:46:38.347Z
Canonical: https://bigchange.ai/blog/shared-ai-training-preference-robots-txt

![AI-generated conceptual illustration of a blank monitor connected to generic server equipment.](https://bigchange.ai/api/media/file/publisher-workstation-concept.png)
AI-generated conceptual illustration by BIG CHANGE; not an actual website, interface or test.

On October 30, OpenAI, Google and Microsoft announced plans for a shared AI training preference.

## The big change

One shared rule can reduce separate provider instructions while leaving Bing search eligibility unchanged. It expresses a use preference, not crawl restrictions; participants must first implement it.

## The proposed token

The [draft](https://datatracker.ietf.org/doc/draft-kelley-aipref-training-preference-signal/) expresses a whole-site training opt-out in `robots.txt`:

```text
User-Agent: __usage_ai-training
Disallow: /
```

The draft also allows path-specific preferences.

This individual Internet-Draft is not endorsed by the IETF and has no formal standards-process standing. 

[OpenAI says](https://openai.com/index/helping-websites-express-ai-training-preferences/) it aims to implement the signal in the coming months and retain its existing crawler controls. [Google plans](https://developers.google.com/search/blog/2026/10/ai-training-control) support in 2027. Google plans to treat the shared opt-out as a Google-Extended disallow when Google-Extended is unspecified. Explicitly allowing Google-Extended makes pages eligible for grounding in Gemini Apps. Provider-specific controls remain available.

BIG CHANGE has not tested provider implementations.

## Training and grounding

Training changes model parameters; grounding informs answers. Crawling retrieves pages.

[Microsoft](https://blogs.bing.com/search/2026/10/your-content-your-choice-clearer-preferences-for-training-and-grounding/) will honor shared training and separate page-level grounding preferences as it crawls from February 1, 2027.

Microsoft says it will disregard legacy training and grounding preferences on detecting new settings. After March 1, 2027, `NoArchive` and `NoCache` no longer express those preferences. By that date, sites using those tags on December 15, 2026 must publish page-level grounding preferences and record temporary Bing Webmaster Tools protection to retain restrictions; it lasts until recrawl or September 30, 2027, whichever comes first.

## Limits

A nonparticipant may ignore the signal. A published preference does not prove compliance.

## Sources

- [OpenAI announcement](https://openai.com/index/helping-websites-express-ai-training-preferences/) — OpenAI commitment and timing.
- [Google Search Central announcement](https://developers.google.com/search/blog/2026/10/ai-training-control) — Google planned treatment and timing.
- [Microsoft Bing announcement](https://blogs.bing.com/search/2026/10/your-content-your-choice-clearer-preferences-for-training-and-grounding/) — Microsoft controls and transition.
- [Machine-Readable Training Preference Signal](https://datatracker.ietf.org/doc/draft-kelley-aipref-training-preference-signal/) — Individual technical draft and status.