Microsoft to buy AI from Anthropic in shift from OpenAI: Report

Microsoft will pay to use Anthropic's technology for some AI features in Office 365 apps, the Information reported on Tuesday, in a sign that the software firm is diversifying its artificial intelligence portfolio.

The move will blend Anthropic and OpenAI technology in the apps, after years in which Microsoft primarily used OpenAI for the new features in Word, Excel, Outlook and PowerPoint, the report said.

Microsoft is developing its own artificial intelligence models, while integrating DeepSeek's models into the Azure cloud as it seeks to maximize AI output to meet growing demand.


It has been OpenAI's biggest financial backer, having invested more than $13 billion into the AI startup and getting a head-start in the AI race due to the company's models.

"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 said.

Developers making Office AI features found Anthropic's latest models performed better than OpenAI in automating tasks such as financial functions in Excel or generating Powerpoint presentations based on instructions, the report said, citing one of the two people involved in the effort.

Microsoft will pay its cloud rival Amazon Web Services to access the Anthropic models, according to the report. AWS is one of Anthropic's largest shareholders.

Anthropic, and OpenAI did not immediately respond to Reuters requests for comment, while AWS declined to comment.

OpenAI's launch of GPT-5 is a step up in quality but Anthropic's Claude Sonnet 4 performs better in creating Powerpoint presentations that are more aesthetically pleasing, the report said.

Microsoft plans to announce the move in the coming weeks, while the price of AI tools in Office will stay the same, the report said.