Microsoft has been working on adding in-house and third-party artificial intelligence models to support its flagship artificial intelligence product, Microsoft 365 Copilot, diversifying existing OpenAI-based technologies and reducing costs, according to sources. Microsoft is a major supporter of OpenAI, and this time Microsoft seeks to reduce its reliance on the artificial intelligence startup, unlike in recent years when Microsoft has touted its accessible OpenAI models. In addition to training its own small models, including the latest Phi-4, Microsoft is working on customizing other open models to make 365 Copilot faster and more efficient, sources said. The goal is to reduce Microsoft's cost of running 365 Copilot and potentially pass on the savings to end point customers.