Microsoft announced strong gains from its investment in the AI startup Anthropic in its fourth-quarter fiscal 2026 earnings report ending June 30, 2026. The tech giant recorded a $3.2 billion uptick in the value of its Anthropic stake during the quarter, which boosted diluted earnings per share (EPS) by 33 cents. Microsoft had invested $5 billion in Anthropic in November 2025, as part of a strategic partnership that also involved Anthropic committing to spend $30 billion on Microsoft's Azure cloud services.

In contrast, Microsoft’s investment in its other major AI partner, OpenAI, experienced a setback in the same quarter. The company took a $600 million markdown on its OpenAI holdings, resulting in a 7-cent reduction in diluted EPS. Microsoft currently owns roughly 27% of OpenAI, but the quarterly valuation updates indicate some volatility in that investment’s short-term worth. Despite this quarterly dip, OpenAI’s investment showed impressive results over the full 2026 fiscal year.

Over the entire fiscal year, Microsoft reported a $5 billion gain from its OpenAI stake, which contributed an additional 67 cents to its EPS, reflecting more positive overall performance than the quarterly numbers suggested. This annual gain helped drive Microsoft’s fiscal 2026 earnings per share to $17.95, underscoring the longer-term value the company perceives in OpenAI even as short-term fluctuations occur.

Microsoft’s overall financial performance remained robust, with the company posting $90 billion in revenue and $35.8 billion in net income for the quarter, and $331.8 billion in revenue along with $133.7 billion in net income for the full fiscal year. The notable quarter-over-quarter contrast between its Anthropic and OpenAI investments highlights the competitive and rapidly evolving nature of the AI sector where Microsoft is actively placing big, strategic bets.