Microsoft’s $5 billion bet on Anthropic is already paying off faster than its far older, far larger stake in OpenAI. That’s the buried story inside an otherwise blowout earnings report. According to TechCrunch, Microsoft logged a $3.2 billion gain on its Anthropic investment in Q4 alone, compared to a $5 billion gain on OpenAI across the entire fiscal year. Those two numbers sitting side by side are hard to ignore.
Here’s the setup. Microsoft put $5 billion into Anthropic in November 2025 as part of a circular deal where Anthropic also committed to purchasing $30 billion in Azure cloud services. It’s the kind of agreement that benefits Microsoft twice over: as an investor and as a cloud vendor. Microsoft doesn’t update the Anthropic valuation every quarter, which makes the Q4 disclosure feel deliberate. They chose to surface this number, which suggests they wanted the market to notice.
The OpenAI picture is more complicated. Microsoft owns roughly 27% of OpenAI and also receives revenue-share payments from the company, though it doesn’t break out how much. What it does report is the mark-to-market value of its OpenAI stake, and in Q4, that dropped by around $600 million, shaving about 7 cents off diluted earnings per share. For a company reporting $90 billion in quarterly revenue and $35.8 billion in net income, a $600 million write-down barely registers. But the directional signal still matters.
OpenAI has had a complicated year. Structural changes, executive departures, and the ongoing transition to a for-profit model have introduced real uncertainty around its valuation. None of that means OpenAI is in trouble, but it does mean Microsoft’s stake is harder to price with confidence. Anthropic, by contrast, has been on a steadier trajectory, with Claude gaining ground in enterprise settings and the company staying out of the kind of public turmoil that surrounded OpenAI in 2024 and into 2025.
For developers and founders evaluating which AI ecosystem to build on, this financial dynamic is worth tracking. When Microsoft’s own balance sheet shows stronger near-term returns from Anthropic than from OpenAI, that’s a signal about internal conviction, not just accounting. Microsoft is deeply embedded with both companies, but capital allocation tells a story that press releases don’t always tell clearly.
The full-year numbers for fiscal 2026: $331.8 billion in revenue, $133.7 billion in net income, and $17.95 in diluted EPS. Microsoft is not a company that needs either investment to go well. But it is a company that knows exactly what it’s communicating when it decides to highlight a $3.2 billion gain in a single quarter.
