Ann Altman, the younger sister of OpenAI’s chief executive and founder, Sam Altman, filed a lawsuit in a Missouri federal court on Monday accusing him of sexually abusing her when she was a minor.
The suit, filed in U.S. District Court for the Eastern District of Missouri, said that the abuse occurred in the Altman’s family home outside St. Louis from 1997 to 2006 and started when Ms. Altman was 3 years old.
The lawsuit said Ms. Altman had sustained bodily injury and had “experienced PTSD, severe emotional distress, mental anguish and depression, which is expected to continue into the future,” as a result of the abuse.
Ms. Altman has long made similar sexual assault claims against her brother on social media services like X. She is represented by an Illinois-based law firm that specializes in sexual assault and harassment cases.
In a statement posted to X on Tuesday, Mr. Altman, along with his mother and two younger brothers, denied the claims. “Annie has made deeply hurtful and entirely untrue claims about our family, and especially Sam,” the statement said. “This situation causes immense pain to our entire family.”
The statement said that Ms. Altman had “mental health challenges” and “refuses conventional treatment and lashes out at family members who are genuinely trying to help.”
Ms. Altman and Mr. Altman did not respond to requests for comment.
Since OpenAI released the online chatbot ChatGPT in late 2022, Mr. Altman has gained widespread fame as the face of the global artificial-intelligence boom set off by the chatbot, which can answer questions, write poetry and even generate computer programs. In October, OpenAI completed a new funding deal that valued the company at $157 billion.
(The New York Times sued OpenAI and Microsoft, accusing them of copyright infringement of news content related to A.I. systems. OpenAI and Microsoft have denied those claims.)
Ms. Altman’s lawsuit requests a jury trial and damages in excess of $75,000. Ms. Altman’s lawyer, Ryan Mahoney, said in an interview with The Times that the amount was the minimum required for a federal suit of this kind. He said that if the suit proceeded to a jury trial, he and his client would seek “an amount that fully compensates my client for what happened to her.”
He added that they were also seeking punitive damages that would be based on Mr. Altman’s net worth.
Mr. Mahoney said the suit was filed on Monday because of a Missouri statute that allowed survivors of childhood sexual abuse to bring a lawsuit up to 10 years after their 21st birthday. Ms. Altman turned 31 on Wednesday.
