Elon Musk and Sam Altman founded OpenAI together, but are now at odds in a lawsuit. Here’s the history of their working relationship and feud.

• Elon Musk helped found OpenAI, but he has frequently criticized it in recent years and is now suing.
• OpenAI CEO Sam Altman has called Musk a “jerk” but said the Tesla CEO “really does care” about AI risks.
• Here’s a history of Musk and Altman’s working relationship.

Elon Musk and Sam Altman lead rival AI firms and now take public jabs at each other — but it wasn’t always like this.

Years ago, the two cofounded OpenAI, which Altman now leads. Musk departed OpenAI, which created ChatGPT, in 2018 and recently announced his own AI venture, xAI, and AI chatbot, Grok.

Now, Musk is suing Altman and OpenAI, saying they’ve betrayed the firm’s founding principles, namely of being open-source and “a nonprofit developing AGI for the benefit of humanity.”

Here’s a look at Musk and Altman’s complicated relationship over the years: