Heads up if you run Microsoft 365 for a UK organization. Starting December 9, Microsoft will enable Anthropic’s Claude models for UK Copilot tenants whose admins haven’t picked a setting. Doing nothing means opting in.
Why it matters
Anthropic acts as a Microsoft subprocessor here and processes the data in the United States. Claude is already on by default for most commercial tenants, but the EU, EFTA and UK were exceptions. The UK isn’t covered by Microsoft’s EU Data Boundary, so Microsoft is flipping it there. Microsoft is also retiring the setting that limited Claude to Microsoft 365 alone.
What to do
If you’re a UK admin, decide before Dec. 9 whether US processing fits your compliance rules, and set it explicitly either way. I don’t like default-on for anything that moves data across borders. A choice this big should be opt-in.
God Bless, and Needs Garlic!
