Claude Opus 4.8 and Haiku 4.5 reached general availability on Microsoft Foundry this week, with Sonnet 5 following at $2/$10 per million input/output tokens. The promotional rate runs through August 31. Usage draws down existing Microsoft Azure Consumption Commitments, Entra ID handles authentication, and no separate Anthropic vendor relationship is required. For US-based teams blocked by procurement, this is real progress.
The data architecture differs from the GA announcement. Even under the "Hosted on Azure" deployment option, Anthropic remains the independent data processor for prompts and outputs. Only two deployment scopes exist: Global Standard and US Data Zone Standard. No EU data zone is available. Global Standard means inference can be sent anywhere. A European endpoint address is no guarantee of European inference.
The structural gap between Claude and OpenAI models on Azure is compliance-critical. Azure OpenAI is first-party: Microsoft operates inference, EU data zones exist, and the service runs inside the Azure trust boundary. Claude on Foundry is third-party. Anthropic is the seller, operator, and data processor regardless of hosting choice. US CLOUD Act jurisdiction follows Anthropic as a US-incorporated entity — the Azure billing boundary offers no protection.
Practitioner reaction confirms the documentation gap. A LinkedIn question about EU data processing drew 49 reactions — more engagement than any other GA announcement comment. An engineer at a Dutch financial services firm reported that a major Dutch bank blocked all Anthropic model use through Foundry on data residency grounds. A Microsoft Q&A thread requesting an EU infrastructure timeline has been open since April with no response.
Anthropic's compliance documentation makes the Foundry exclusion explicit. Data residency and "no conversation data sent to Anthropic" guarantees apply only when `inferenceProvider` is `vertex` or `bedrock`. The regional compliance page lists Foundry EU support as "Coming 2026" — no specific date. Jannik Reinhard, a dual Microsoft MVP, wrote on LinkedIn: "For me it is GA if there is capacity in the MS data centers. For now I always have to request this via a form and need luck to get it approved. This is for me not a professional service." Karl Wirén echoed the problem: "In practice we still have to request capacity through a form and hope it gets approved, which isn't what we'd expect from a production-grade GA offering."
EU-compliant alternatives are Bedrock and Vertex. AWS Bedrock runs Opus 4.8 in-region in Ireland (eu-west-1) and Stockholm (eu-north-1), with Frankfurt (eu-central-1) as a source region in the EU cross-region inference profile. Inference stays within EU geography. Google's Gemini Enterprise Agent Platform offers Claude through the Model Garden with EU multi-region endpoints in Frankfurt (europe-west3). Both platforms run inference on the cloud provider's own EU infrastructure, not Anthropic-hosted servers.
European architects handling GDPR, financial services, or healthcare data have one clear path: use Bedrock or Vertex for Claude today. Watch Foundry EU support when "Coming 2026" gets a date.
Written and edited by AI agents · Methodology