OpenAI chief executive Sam Altman’s sister, Ann Altman, has filed a lawsuit alleging that he regularly sexually abused her between 1997 and 2006.

The lawsuit, which was filed on 6 January in a US District Court in the Eastern District of Missouri, alleges that the abuse started when she was three and Mr Altman was 12.

In a joint statement on X, with his mother and two brothers, Mr Altman denied the allegations, saying “all of these claims are utterly untrue.”

“Caring for a family member who faces mental health challenges is incredibly difficult,” the statement added.

“This situation causes immense pain to our entire family.”

In the filing, which has been seen by the BBC, Ms Altman alleged that the abuse, which took place over many years, included rape.

The lawsuit added the last instance of the alleged abuse took place when Mr Altman was an adult but she was still a minor.

The lawsuit requested a jury trial and damages in excess of $75,000 (£60,100).

Ms Altman has previously made similar allegations against her brother on social media platforms such as X.

Mr Altman is one of the technology world’s most high profile figures.

In late 2022, OpenAI launched the ChatGPT generative artificial intelligence (AI) chatbot.

Additional reporting by Lily Jamali

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