Microsoft and OpenAI have had something of a symbiotic relationship, with the former giving billions of capital to a startup AI lab and in return gaining early access to cutting-edge models that are now baked into Microsoft’s suite of productivity software.

Microsoft (NASDAQ:MSFT) is working on integrating artificial intelligence models from other companies aside from OpenAI and itself into its Office 365 Copilot products, Reuters reported. Microsoft shares fell fractionally in late afternoon trading on Monday.

The effort is said to focus on the tech giant’s Microsoft 365 Copilot product. It’s an artificial intelligence assistant that ships with the eponymous productivity suite. Microsoft is reportedly working to integrate custom and open-source artificial intelligence models into the assistant, which is currently powered by technology from OpenAI.