
4/29/2026

The court case that pits the world's richest man, Elon Musk, against ChatGPT developer OpenAI and its CEO, Sam Altman, has kicked off in California federal court. The man behind Tesla and SpaceX is suing OpenAI, arguing the company ditched its charitable mission of safe AI research in pursuit of profits.
A jury is hearing testimony about OpenAI’s early years, its shift to a for‑profit structure, and Musk’s role as an early investor and a co-founder. A star-studded witness list is set to testify over the next few weeks. Musk has started his testimony, with Altman and Microsoft CEO Satya Nadella in the hot seat later.
Musk argues that Altman and OpenAI President Greg Brockman turned a nonprofit research lab into a commercial giant valued above $800 billion. In his testimony, Musk compared OpenAI to a museum store that has taken over the whole museum.
He wants the court to order:
Altman has faced attempts to remove him before, including the 2023 board revolt over AI safety that briefly pushed him out.
OpenAI says Musk is driven by rivalry, not principle. They claim he ignored the nonprofit after leaving, raised no concerns when Microsoft invested $1 billion in 2019, and filed the lawsuit in 2024 only after ChatGPT’s breakout.
Moreover, Musk proposed folding OpenAI into Tesla before leaving in 2018. OpenAI argues that it was Musk who was pushing OpenAI to become more commercial in its operations.
Lawyers cite internal messages where Musk mocked staff focused on safety. OpenAI says the for‑profit structure was needed to buy computing power and hire researchers.

Microsoft, also a defendant, has recently loosened its ties with OpenAI through a revised deal:
Microsoft keeps its $135 billion stake but says it is “dissociated” from OpenAI’s internal drama.

This trial has the world's richest man, armed with nearly $800 billion, fighting against another billionaire (Altman’s net worth is estimated at a “modest” $3 billion).
But at stake is more than bruised tech-bro egos: the case could set a precedent for what nonprofit AI research means and how far companies can go in turning public‑interest missions into profit‑driven businesses.
Both OpenAI and Musk’s SpaceX are preparing for blockbuster IPOs. SpaceX owns xAI and its chatbot Grok, competing directly with OpenAI.
OpenAI's and SpaceX's rival, Anthropic, is also reportedly planning to list its shares. Together, the three companies could be valued at over $3 trillion in public markets.
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