Microsoft Uses Own MAI Tech To Replace OpenAI, Anthropic In Office Apps

The company has begun integrating its proprietary MAI models into Excel, Outlook, and GitHub Copilot, phasing out reliance on external AI providers. The move is driven by cost efficiency, as MAI models are cheaper to run at scale, according to sources familiar with the plan.

Microsoft has been developing MAI as part of a broader strategy to reduce dependence on third-party AI vendors. The shift affects key productivity tools used by millions of businesses worldwide, though the company has not disclosed a timeline for full deployment.

The transition follows months of internal testing where MAI models matched or exceeded the performance of OpenAI's GPT-4 and Anthropic's Claude in specific tasks like email drafting and spreadsheet analysis. GitHub Copilot, Microsoft's coding assistant, will also use MAI for code suggestions.

Analysts note that this move could pressure OpenAI and Anthropic, which rely on Microsoft as a major customer and investor. Microsoft remains an investor in OpenAI but has increasingly signaled its intent to build independent AI capabilities.

The company has not commented on whether the change will affect pricing for Microsoft 365 subscribers. Early reports suggest the switch will not alter user-facing features, but may improve response times and reduce operational costs.