Who Owns OpenAI?

OpenAI is controlled by the OpenAI Foundation, a nonprofit. Since a restructuring completed in October 2025 the business is OpenAI Group PBC, a public benefit corporation whose board is appointed by the Foundation. Microsoft holds the largest external stake at roughly 27%, more than the Foundation’s ~26% — and does not control the company. Ownership verified 5 September 2026.

Who owns OpenAI today?

OpenAI is not one entity. The nonprofit OpenAI Foundation sits at the top and holds control. Beneath it, OpenAI Group PBC is the for-profit company that employs the staff, raises the capital and operates the products.

A public benefit corporation is a specific US company form: it must weigh a stated public purpose alongside shareholder returns, rather than being obliged to maximise returns alone. That is the point of the structure, not incidental to it.

Ultimate parent and corporate structure

The Foundation is the ultimate controlling body. Its board appoints the board of OpenAI Group PBC, which is how control is exercised — through governance rights, not through the size of a shareholding.

The reported split at the October 2025 recapitalisation:

• OpenAI Foundation — around 26% of the equity, and full control
• Microsoft — around 27% on an as-converted basis, the largest external holder
• Employees and other investors — the remaining ~47%

This is the clearest case on the site of economics and control coming apart in opposite directions from the usual. Elsewhere a founder holds small economics and large votes through dual-class shares — Meta, Alphabet. Here a nonprofit holds smaller economics than Microsoft and controls the company through board appointment.

Major shareholders or controlling persons

Microsoft is the largest external shareholder. It is not the owner and it does not control OpenAI: it appoints no board majority, and the Foundation’s governance rights sit above its stake. “Microsoft owns the largest share of OpenAI” is accurate. “Microsoft owns OpenAI” is not, and the difference is the whole structure.

A funding round in early 2026, reported at around $110 billion with backing including SoftBank and Nvidia, diluted existing holders. So the October 2025 percentages are already stale as economic figures even though the control arrangement is unchanged — which is exactly why control and economics have to be reported separately.

Official records and evidence

The UK register is worth checking precisely because of what it does not contain. OPENAI UK LTD (14367667), incorporated 21 September 2022, files a statement that it knows of no registrable person or relevant legal entity with significant control. That is a legitimate filing, and its effect is that Companies House provides no evidence at all about who owns OpenAI.

Name matching is also unusually unreliable here. OPENAITECH LTD (14178632) is an unrelated business, and the dissolved CHATGPT OPENAI AI ROBOT LTD (14771302) was never part of the group.

OpenAI Group PBC is a private US company with no public filing equivalent to a UK register. The figures above are reported from the restructuring and subsequent rounds, not verified against any register, and should be read with a date attached.

Ownership history and changes

OpenAI was founded in 2015 as a nonprofit research organisation. In 2019 it added a capped-profit arm to raise capital and took its first major Microsoft investment. The decisive change came in October 2025, when the recapitalisation created OpenAI Group PBC under the OpenAI Foundation and converted Microsoft’s position into conventional equity. Microsoft’s commercial arrangement was loosened further in April 2026.

Related companies and brands

OpenAI operates ChatGPT, its API, the Sora video models and the DALL·E image models. Very many consumer products are built on the OpenAI API with no ownership relationship whatsoever — using the technology is not evidence of common ownership, and that inference is the most frequent error made about AI companies.