By Rob Nicholls
Publication Date: 2026-04-29 06:02:00
There was a time when Elon Musk and Sam Altman were friends. But the two tech billionaires are now embroiled in a bitter legal battle in the United States that could change not only OpenAI, the artificial intelligence (AI) company behind ChatGPT, which they co-founded in 2015, but also the future of technology in general.
The lawsuit, launched by Musk in 2024, is the culmination of a years-long feud surrounding OpenAI’s evolution from a nonprofit to a for-profit company.
The trial, which began this week in California, is expected to last about three weeks. But the aftereffects were felt for many years.
The case and the cast
The lawsuit pits Musk against Altman, OpenAI President Greg Brockman, OpenAI itself and Microsoft, the AI company’s biggest backer.
Musk was a co-founder of OpenAI and contributed around $44 million to the financing. According to his own testimony on the witness stand this week, he “came up with the idea, the name, recruited the key…”