Greg Brockman's story of the split with Elon Musk starts with a 'haunted mansion'

Greg Brockman arriving in court on Monday

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• OpenAI cofounder Greg Brockman returned for a second day of testimony at the Musk v Altman trial.
• He recalled a "celebratory" gathering where Musk's then-girlfriend, Amber Heard, served whiskey.
• Musk was excited by OpenAI's for-profit prospects — then resigned in a fight over control, he said.

In the summer of 2017, Elon Musk hosted a festive gathering for OpenAI's cofounders at his Bay Area "haunted mansion." Amber Heard...