Microsoft is starting to replace OpenAI and Anthropic with its own AI models in software products like Excel and Outlook, according to Bloomberg.
A person familiar with the matter said that tens of thousands of AI prompts in the widely used spreadsheet and email applications are now being completed each week with Microsoft’s internally built MAI model. Microsoft had previously relied on models from OpenAI and Anthropic.
This comes as Microsoft is making progress in its efforts to build competitive artificial intelligence models at a lower cost. AI model chief Mustafa Suleyman said in June the company was trying to reduce spending on Anthropic by using more MAI models.
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The report mentioned that Microsoft uses a huge number of tokens in products like its workplace assistant Copilot. While the company currently gets a lot of technology at a discount because of its tie-up with OpenAI, that arrangement could come to an end.
Microsoft announced seven new AI models at its annual Build conference for developers in June. The company mentioned one of these models can match the coding capabilities of Anthropic’s Opus 4.6 at a reduced cost. “We pay a lot of money to Anthropic — so our goal is to reduce and ultimately eliminate that cost,” Suleyman said at the time.
Microsoft’s MAI models are also available for use within GitHub Copilot, the company’s service for AI-assisted software development. Suleyman has said that a Microsoft-built model for transcription will start being used with the Teams video conference apps and other products in the coming months.
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OpenAI and Microsoft have been reportedly drifting apart amid shifting business priorities. The ChatGPT-maker is planning to launch its own platform to compete with LinkedIn, which Microsoft owns. It is also planning to start mass producing its own AI chips in partnership with Broadcom starting next year, which would make it less dependent on Microsoft’s Azure for AI model training and inference.
As OpenAI works to restructure itself as a Public Benefit Corporation (PBC), Microsoft is reportedly in talks with the startup to secure a greater stake than it currently owns and to ensure it would continue to have access to OpenAI’s systems if and when the ChatGPT-maker achieves artificial general intelligence (AGI).
“As we’ve said, OpenAI will continue to be our partner on frontier models and we remain committed to our long-term partnership,” a Microsoft spokesperson told ZDNET.