The head of the company that created Chat GPT has been accused in a federal civil lawsuit of sexually assaulting his younger sister over a period of nine years.

Ann Altman filed the suit against her brother Sam, the founder and CEO of OpenAI, on Monday in the Eastern District of Missouri. Although neither sibling still lives in the St. Louis area, the suit says the assaults took place at the family home in Clayton.

Ann Altman claims her brother raped and assaulted her from the time she was 3 until she was 8 or 9. She alleges the last assault took place when Sam Altman was older than 18.

Sam Altman and the rest of his family denied the allegations in a post on X. “Our family loves Annie, and is very concerned about her well-being,” they wrote. “All of these claims are utterly untrue. This situation causes immense pain to our family. It is especially gut-wrenching when she refuses conventional treatment and lashes out at family members who are genuinely trying to help.”

They wrote that the family has provided Ann Altman with monthly financial support, paid her rent and bills, offered to buy her a house and attempted to get her medical help.

Ann Altman made similar claims on social media in 2021. She is seeking thousands of dollars in damages in the lawsuit.

Correction: A previous version of this story misspelled Ann Altman's first name.

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