The OpenAI CEO took the witness stand Tuesday to defend his business record in a trial that has invited further scrutiny of Altman’s leadership after testimony from former board members last week.

Musk’s lawsuit accusing Altman and OpenAI of abandoning their mission as a non-profit has shed light on their workings at the artificial intelligence giant.

Altman took the stand Tuesday during a high-stakes trial brought to court by Elon Musk.