OpenAI, Google, Microsoft and Anthropic Back Shared AI-Training Opt-Out Signal
The proposed robots.txt signal would communicate training preferences across participating providers. Rollout schedules differ, and the mechanism is neither a finalized IETF standard nor a technical barrier to scraping.
Four major AI providers are backing a common training-preference signal, with implementation extending into 2027. Publisher control will still depend on provider compliance and company-specific policies.












