Microsoft logs $3.2B from Anthropic investment, but OpenAI was a mixed bag

Microsoft reported strong fiscal Q4 2026 earnings and disclosed a large unrealized gain from its Anthropic stake, marking the investment up by $3.2 billion and adding 33 cents to diluted EPS. That gain contrasted with a roughly $600 million write-down on its OpenAI investment, which reduced EPS by about 7 cents in the quarter. The OpenAI stake still produced a $5 billion gain for the full fiscal year, but the article highlights that Microsoft’s Anthropic gain in just one quarter nearly matched the annual OpenAI contribution, underscoring the divergent performance of its two high-profile AI bets. Overall, the investment gains were material but secondary to Microsoft’s very strong fundamentals, with quarterly revenue of $90 billion and net income of $35.8 billion. The piece is a market-relevant look at how AI investment accounting is affecting Microsoft’s reported earnings and investor perception of its AI ecosystem exposure.