4 AI firms back a single opt-out for websites

OpenAI, Google, Microsoft and Anthropic will honour one shared signal that lets websites block AI training, The Verge reported on the 30th of October 2026. Today sites must block each AI company one by one.

The signal sits in robots.txt, a small file that tells web robots which pages they may read. OpenAI confirmed its plan in a blog post the same day.

How it works

The shared signal was proposed by Kevin Kelley, a standards lead at Anthropic, The Verge reported. It is part of work at the Internet Engineering Task Force, a group that sets web rules.

When the four companies' robots find the signal, they will stay away from the site's content for AI training.

When it starts

Anthropic already uses the signal, The Verge reported. Google and Microsoft plan to support it next year, and OpenAI said it will in the coming months.

Microsoft said sites that opt out will still appear in Bing search results. Meta said it supports the idea but gave no promise to honour it.

Why it matters

Publishers say AI robots copy their pages to train models without asking. OpenAI said its current blocking tools will keep working.

Below we break down the work saved

A site that wants to block four AI companies now needs four separate rules. With the shared signal it needs one, which is three fewer, by our arithmetic.

Key facts

OpenAI, Google, Microsoft and Anthropic back one shared AI training opt-out.

The signal lives in a website's robots.txt file.

Anthropic uses it now; Google and Microsoft start next year.

OpenAI says it will follow in the coming months.