OpenAI confirmed that its latest GPT 5.6 model will serve as the backbone for Microsoft Copilot 365, the AI assistant embedded across Word, Excel, PowerPoint, and other Microsoft 365 applications. The designation comes as the two companies navigate a complex partnership amid recent reports of tension and potential restructuring.
Microsoft has relied on OpenAI's models since integrating Copilot into its productivity suite. The choice of GPT 5.6 as the "preferred model" signals continued confidence in OpenAI's capabilities, even as both companies explore alternative arrangements. Microsoft has been developing its own AI models and exploring partnerships with other providers like Mistral, signaling a diversification strategy that reduces exclusive dependence on OpenAI.
The GPT 5.6 family represents OpenAI's latest advancement in language capabilities. By positioning it as the primary engine for Copilot 365, OpenAI ensures its models reach millions of enterprise users daily. Microsoft 365 boasts over 400 million users globally, making Copilot 365 a critical distribution channel for OpenAI's technology.
The timing of this announcement matters. Earlier reports suggested potential friction between OpenAI and Microsoft over pricing, governance, and the direction of AI development. Some coverage indicated Microsoft might reduce its reliance on OpenAI or even end the partnership entirely. OpenAI's explicit statement that GPT 5.6 is "preferred" appears designed to reinforce stability and commitment to the relationship.
Both companies have commercial incentives to maintain the partnership. Microsoft depends on OpenAI's models for differentiation in the competitive productivity software market. OpenAI needs Microsoft's distribution network and substantial financial backing to compete against rivals like Anthropic and Google. The relationship generated billions in revenue for both parties.
GPT 5.6's selection for Copil