Microsoft Leans on Anthropic’s Claude, Raising Questions About OpenAI Ties

Microsoft will integrate Anthropic’s Claude into Office 365, citing stronger performance in tasks like Excel and PowerPoint as tensions with OpenAI grow.

Microsoft is bringing Anthropic’s Claude into Office 365, edging away from its dependence on OpenAI.

According to The Information, Microsoft developers found that Anthropic’s AI outperformed OpenAI in automating tasks such as financial functions in Excel. The move, set to be announced in the coming weeks, blends Anthropic’s technology with OpenAI’s in Office apps.

Cleaner presentations from simple prompts

Tests showed Anthropic’s model generated “more aesthetically pleasing” PowerPoint slides from basic prompts. To support the rollout, Microsoft will tap Amazon Web Services, Anthropic’s primary cloud partner.

Microsoft chose Claude Sonnet 4, not even Anthropic’s flagship, after it outperformed OpenAI in productivity tasks. Company sources told The Information the model “performs better in subtle but important ways” than GPT-5.

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