Microsoft Shifts Copilot to In-House AI Models to Cut Costs

According to Bloomberg, Microsoft is gradually replacing OpenAI and Anthropic models with its in-house MAI models for some Copilot traffic in products like Excel and Outlook. This move has attracted widespread community attention as a significant step for Microsoft to reduce external reliance and advance its proprietary model strategy.

Key Details and Cost Considerations

The core driver behind this shift is cost reduction. Multiple authors highlighting the event noted that continuing to use cutting-edge closed-source models is no longer cost-effective. Microsoft aims to optimize Copilot's operating expenses by reducing its dependence on external labs that control the pricing of frontier models. Currently, this model transition already covers tens of thousands of weekly prompts.

Strategic Impact

Beyond direct economic benefits, this adjustment marks a crucial shift in Microsoft's AI strategy and model supply chain. By advancing its proprietary AI models, Microsoft is not only building a more autonomous tech ecosystem but also mitigating its over-reliance on a single third-party provider.

2026-07-08 ~ 2026-07-09 · 6 related posts

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