OpenAI’s Sam Altman denies sexual abuse allegations made sister, Ann

OpenAI CEO Sam Altman’s sister, Ann Altman, filed a lawsuit on Monday, alleging that her brother sexually abused her regularly between the years of 1997 and 2006.

The lawsuit, which was filed in U.S. District Court in the Eastern District of Missouri, alleges that the abuse took place at the family’s home in Clayton, Missouri, and began when Ann, who goes by Annie, was three and Sam was 12. The filing claims that the abusive activities took place “several times per week,” beginning with oral sex and later involving penetration.

The lawsuit claims that “as a direct and proximate result of the foregoing acts of sexual assault,” the plaintiff has experienced “severe emotional distress, mental anguish, and depression, which is expected to continue into the future.”

The younger Altman has publicly made similar sexual assault allegations against her brother in the past on platforms like X, but this is the first time she’s taken him to court. She’s being represented by Ryan Mahoney, whose Illinois-based firm specializes in matters including sexual assault and harassment.

The lawsuit requests a jury trial and damages in excess of $75,000.

In a joint statement on X with his mother, Connie, and his brothers Jack and Max, Sam Altman denied the allegations.

“Annie has made deeply hurtful and entirely untrue claims about our family, and especially Sam,” the statement said. “We’ve chosen not to respond publicly, out of respect for her privacy and our own. However, she has now taken legal action against Sam, and we feel we have no choice but to address this.”

Their response says “all of these claims are utterly untrue,” adding that “this situation causes immense pain to our entire family.” They said that Ann Altman faces “mental health challenges” and “refuses conventional treatment and lashes out at family members who are genuinely trying to help.”

Sam Altman has gained international prominence since OpenAI’s debut of the artificial intelligence chatbot ChatGPT in November 2022. Backed by Microsoft, the company was most recently valued at $157 billion, with funding coming from Thrive Capital, chipmaker Nvidia, SoftBank and others.

Altman was briefly ousted from the CEO role by OpenAI’s board in November 2023, but was quickly reinstated due to pressure from investors and employees.

This isn’t the only lawsuit the tech exec faces.

In March, Tesla and SpaceX CEO Elon Musk sued OpenAI and co-founders Altman and Greg Brockman, alleging breach of contract and fiduciary duty. Musk, who now runs a competing AI startup, xAI, was a co-founder of OpenAI when it began as a nonprofit in 2015. Musk left the board in 2018 and has publicly criticized OpenAI for allegedly abandoning its original mission.

Musk is suing to keep OpenAI from turning into a for-profit company. In June, Musk withdrew the original complaint filed in a San Francisco state court and later refiled in federal court. 

Last month, OpenAI clapped back against Musk, claiming in a blog post that in 2017 Musk “not only wanted, but actually created, a for-profit” to serve as the company’s proposed new structure.

WATCH: OpenAI unveils for-profit plans