Elon Musk and Sam Altman cofounded OpenAI together years ago, but they're frequently at odds today. Altman says OpenAI is "not for sale" after group led by Musk made a $97.4 billion unsolicited bid.

Here’s how Elon Musk and Sam Altman fell out ... look of absolute certainty on his face when he talked about sending large rockets to Mars,” wrote Altman. “I left thinking ‘huh, so ...