[UPDATE] Copilot | Claude Fable 5 Available

Microsoft is expanding the model selection in Microsoft 365 Copilot. Anthropic's Claude Fable 5 is now available as an additional model option. Alongside OpenAI models, organizations now gain access to a second frontier model that Microsoft specifically positions for longer, multi-step workflows.

Claude Fable 5 is designed for tasks that extend beyond single prompts. It excels at multi-step processes where intermediate results are refined and fed into subsequent stages of work.

Because the model is integrated through Work IQ, Copilot can place tasks and outputs into a real business context. It can leverage files, meetings, chats, and organizational data, allowing responses to be grounded in tenant content rather than relying solely on general-world knowledge.

For administrators, the most important detail is that the model is disabled by default.

You decide whether Claude Fable 5 is enabled and who can access it, applying your organization's governance and compliance requirements. Activation is performed through the Microsoft 365 Admin Center under the Copilot setting "AI models in preview", where Microsoft currently classifies Anthropic models as experimental.

The Copilot options page contains the controls for experimental features and preview models.

Under "Available experimental models for your organization", you can selectively enable Claude Fable 5 for your tenant and assess readiness before deployment.

One area deserves particular attention: Anthropic's data processing and retention policies.

Because requests are processed by an Anthropic model, Anthropic's data handling terms also apply. Before enabling the model, verify whether those requirements align with your compliance framework, especially for GDPR obligations and internal data governance policies.

Microsoft explicitly recommends that organizations evaluate this aspect as part of their activation decision.

The current limitation is considered temporary. Microsoft has announced that Claude is expected to support EU Data Boundary processing during summer 2026, allowing data processing to remain within the European Union.

With only a short period remaining until that capability becomes available, organizations that prohibit processing outside the EU may prefer to delay activation rather than introduce and document a temporary compliance exception.

Claude Fable 5 launches as an option within Copilot Cowork, while Excel and PowerPoint support are currently available through a private preview program.

The rollout is being delivered gradually. Availability depends on region and tenant configuration. If the option is not yet visible in your tenant, it is often simply a matter of rollout timing rather than a configuration issue.

Model choice within Microsoft 365 Copilot is becoming increasingly meaningful, and that is a positive development because different workloads benefit from different model strengths.

For administrators, this means making an intentional activation decision rather than relying on automatic rollout. Review Anthropic's data retention policies against your compliance requirements first, then begin with a controlled pilot group in Copilot Cowork.

For complex, multi-step workflows that benefit from Work IQ context integration, Claude Fable 5 is well worth evaluating.