Microsoft Owns More of OpenAI Than the Nonprofit Does. So Why Doesn't Microsoft Control It?

In late October 2025, OpenAI finished a restructuring it had spent nearly a year negotiating. The nonprofit became the OpenAI Foundation. The business became OpenAI Group PBC, a public benefit corporation, which is a company legally required to weigh its stated mission alongside returns to shareholders.

Then look at the ownership. The Foundation holds about 26% of the company. Microsoft holds about 27%. Employees, former employees, and other investors hold the rest.

Microsoft owns more. The Foundation controls the company.

At most companies those two line up. Own a quarter of the shares, get roughly a quarter of the votes. OpenAI was built so that stops being true. Microsoft has put tens of billions of dollars into the company and, as of April 2026, held no board seat at all.

So who decides? As of April 2026, every OpenAI Foundation board member but one also sat on the board of OpenAI Group PBC. The nonprofit exists to check the company, and the people doing the checking are nearly the same people being checked. If the Foundation ever had to overrule the company, it would be overruling itself.

There is already a test case. In November 2023 the board removed Sam Altman as CEO. Within five days he was back and most of that board was gone. The structure said the board could fire the CEO. The first time one tried, the structure lost.

What I would look for: whether the Foundation ever gets directors who sit on it and nothing else, and whether it ever publicly disagrees with the company. A check that has never been used is hard to tell apart from a check that does not work.

The bigger lesson is that the easy question about a company is who owns it. The useful question is who can say no.