OpenAI

OpenAI was founded on 8 December 2015 in San Francisco as a nonprofit research lab by Sam Altman, Greg Brockman, Ilya Sutskever, Elon Musk and others. It is headquartered in San Francisco. A restructuring completed on 28 October 2025 turned the former capped-profit company into OpenAI Group PBC, a public benefit corporation whose board is appointed by the nonprofit OpenAI Foundation. It is privately held, with Microsoft among the largest shareholders.

It builds AI models and the products around them: ChatGPT, the GPT model family, the developer API, the Codex coding agent, GPT Image, Deep Research, ChatGPT agent and the ChatGPT Atlas browser.

OpenAI does not publish a headcount on the pages checked; Wikipedia gives about 4,500 employees in 2026. Besides San Francisco, press reports from 2024 list offices in London, Dublin, Paris, Brussels, Singapore and New York.