OAKLAND, California: Elon Musk and Sam Altman exchanged sharp accusations in closing arguments as a closely watched trial over the future of OpenAI moved toward a jury verdict.

Musk alleges that OpenAI and its leaders betrayed the organization's original nonprofit mission by transforming it into a commercial enterprise designed to enrich insiders and investors.

He is seeking about US$150 billion in damages from OpenAI and Microsoft, with any award to be paid to OpenAI's nonprofit arm. He also wants Altman and OpenAI President Greg Brockman removed from their positions.

Steven Molo, Musk's attorney, told jurors that multiple witnesses had described Altman as untrustworthy.

"Sam Altman's credibility is directly at issue in this case," Molo said. "If you don't believe him, they cannot win."

Molo also criticized Brockman's testimony about the value of his OpenAI stake. "The arrogance, the lack of sensitivity, the failure to account for just common decency is really, really abhorrent," Molo said.

Molo argued that Microsoft knowingly supported OpenAI's conduct. "Microsoft was aware of what OpenAI was doing every step of the way," he said.

OpenAI's lawyers rejected Musk's claims and argued that he wanted to control the company himself.

Sarah Eddy, an attorney for OpenAI, said the company's founders refused to hand control of artificial general intelligence to one person. "Mr. Musk wanted to turn OpenAI into a for-profit company that he could control," Eddy said. "But the other founders refused to turn the keys of AGI ... over to one person, let alone Elon Musk."

Eddy said Musk waited too long to file the lawsuit and questioned his testimony that he did not review key documents in 2018.

William Savitt, another lawyer for OpenAI, said, "Mr. Musk may have the Midas touch in some areas, but not in AI. To succeed in AI, as it turns out, all Mr. Musk can do is come to court."

Russell Cohen, counsel for Microsoft, said the company was "a responsible partner at every step."

The nine-member jury is expected to begin deliberations on May 18.

If Musk wins, U.S. District Judge Yvonne Gonzalez Rogers will decide how OpenAI should be restructured and what damages should be awarded.