OpenAI 's CEO Sam Altman took the witness stand on Tuesday to defend his business record in a trial pitting him against Elon Musk, rebutting testimony that disparaged his leadership at a pivotal time for the ChatGPT maker.

The trial, now in its third week, could determine OpenAI’s structure after it successfully raised billions of dollars in investment for its flagship artificial intelligence frontier model, ChatGPT.

Musk’s lawsuit alleges that Altman persuaded him to donate $38 million to OpenAI when it was a nonprofit, only for the company to shift to a for-profit corporate model in 2018. He argues that his funding was specifically going to a charity.

Under a barrage of questions by a lawyer for Musk, Altman said he did not agree with trial testimony that depicted him as dishonest.

“I believe I am an honest and trustworthy businessperson,” Altman said.