Microsoft recorded a $3.2 billion gain on its stake in Anthropic during the fourth quarter of fiscal 2026, a figure that boosted diluted earnings per share by 33 cents. This result follows a November 2025 agreement where the tech giant invested $5 billion in the AI lab in exchange for a commitment to purchase $30 billion worth of Azure services. By contrast, the company marked down its investment in OpenAI by roughly $600 million for the same period, reducing diluted earnings per share by about 7 cents. Microsoft holds approximately 27% of OpenAI and accounts for the value of that holding on its books, though it does not routinely disclose specific revenue-share payments received from the Boston-based firm.
The disparity highlights the divergent financial trajectories of the two major AI labs under Microsoft’s portfolio. While the OpenAI write-down remains a rounding error against the company’s $35.8 billion net income for the quarter, the single-quarter profit from Anthropic nearly matched the total annual gain Microsoft recorded on its OpenAI stake. This performance suggests that Microsoft’s strategic bet on the London-based company is currently delivering more immediate accounting value than its partnership with the US rival.
- Microsoft invested $5 billion in Anthropic in November 2025.
- The deal requires Anthropic to buy $30 billion of Azure services.
- Anthropic’s quarterly gain equaled OpenAI’s full-year gain.
