Claude Joins Microsoft 365 Copilot: What This Means for Businesses
Microsoft has taken another major step in expanding its AI capabilities within Microsoft 365, adding Anthropic’s Claude models alongside OpenAI’s ChatGPT.
Previously, Copilot relied exclusively on OpenAI models. That’s now changed. Starting with the Researcher tool and Copilot Studio, users can choose between Claude Sonnet 4 and Claude Opus 4.1.
The move reflects Microsoft’s strategy to diversify its AI portfolio amid growing demand for flexibility, performance, and governance. It’s also a signal that the industry is moving towards a multi-model AI landscape, where organisations can choose the right model for the right task rather than a one-size-fits-all approach.
Choice changes everything
With Claude now part of Microsoft 365, organisations can select which model powers their workflows or even use multiple models in tandem.
Different models bring different strengths. Some excel at creative tasks, others at complex reasoning or structured analysis. With Microsoft’s update, customers can select which model to use or even combine them for different workflows to get the best of both worlds.
This flexibility also adds resilience. If one model experiences latency or accuracy issues, organisations can quickly switch to another.
Why Claude stands out
Claude has quickly built a reputation for handling complex queries with precision. It brings a unique set of capabilities that set it apart, especially for complex, regulated, or data-intensive industries.
Claude can handle vast context windows – up to 500,000 tokens – allowing it to process long documents, detailed reports, and large data sets efficiently. It performs exceptionally well in complex Excel operations, document synthesis, and advanced research tasks.
This explains why many technical and regulated sectors are adopting Claude for complex data processing workflows
But there are risks to consider
With Claude now available inside Microsoft 365, organisations, especially regulated ones, need to understand the additional architectural and compliance implications that come with it.
Claude in Copilot does not run within Microsoft’s native Azure environment. Instead, it uses Anthropic-hosted models, meaning organisational data (documents, emails, Teams chats, prompts) can flow to Anthropic infrastructure under Anthropic’s commercial terms.
For regulated organisations, this introduces new questions around:
- How data is processed and stored
- Whether data could leave the required jurisdictions
- What protections exist against leakage or misuse
- How Anthropic’s model-handling aligns with internal security policies
It also introduces Anthropic as a new critical third-party provider, triggering additional oversight expectations under frameworks like the FCA’s operational resilience and outsourcing rules. Senior managers must ensure they understand how data is processed, where it occurs, and what controls are in place. None of these are blockers, but they do require deliberate assessment before adoption.
The bigger picture: The multi-model future
According to Harvard Business Review, 43% of employees now use at least two different large language models for different tasks: ChatGPT for quick, generalist activities, Claude for technical or compliance-heavy work and Copilot for Microsoft-specific productivity.
Microsoft’s decision to integrate Claude into the 365 ecosystem formalises this trend. It empowers users to make smarter choices about which model they use and when, while maintaining data control and compliance alignment.
This also opens up the possibility of a multi-modal AI landscape not just for enterprises that can afford to license different LLM models, but also for small and mid-sized businesses. With this, SMEs can tap into multiple models without compromising on privacy, compliance, or trust.
The future isn’t about picking one model – it’s about using the right one, at the right time, for the right task.
