Fidji Simo is stepping down from her full-time leadership role at OpenAI to focus on recovering from a chronic illness, marking another senior leadership change at the AI company.
She will continue supporting the organization as a part-time advisor.
Simo, who joined the ChatGPT maker in mid-2025 as CEO of Applications and became one of CEO Sam Altman’s closest senior leaders, announced the decision in a post on X on Wednesday. After taking 3 months of medical leave, she said her recovery would take much longer and be more complex than she had expected.
“I am only making this decision now because I failed to make it many times before,” she wrote, adding that she had ignored repeated advice to slow down during the past 7 years of living with her illness.
The 40-year-old French-American executive has been on medical leave since April following a severe flare-up of postural orthostatic tachycardia syndrome (POTS), a neuroimmune condition she has lived with since 2019.
Simo reflected on her journey from growing up in a fishing family in the Mediterranean port of Sete to becoming one of Silicon Valley’s leading executives. “I grew up believing that opportunities were precious and that when they appeared, you grabbed them with both hands,” she wrote. “OpenAI in particular felt like a role that my entire career had been building toward.”
Before joining OpenAI, Simo served as CEO of Instacart from 2021, where she led the grocery delivery company to profitability. Earlier, she spent 10 years at Meta, playing a key role in the company’s shift toward video.
Although she is leaving her full-time position, Simo said she remains committed to advancing AI in healthcare and will continue contributing to OpenAI as an advisor.
Responding to the announcement, Sam Altman shared his support on X. “I am really sad about this and very grateful for all Fidji has done for OpenAI, and even grateful for her friendship and who she is as a person,” he wrote.
“We all wish her the best for a speedy recovery. This sucks.”
Simo’s departure comes during a period of continued leadership changes at OpenAI, which has experienced several executive exits in recent years and has filed for a high-stakes IPO.
Also read: Viksit Workforce for a Viksit Bharat
Do Follow: The Mainstream LinkedIn | The Mainstream Facebook | The Mainstream Youtube | The Mainstream Twitter
About us:
The Mainstream is a premier platform delivering the latest updates and informed perspectives across the technology business and cyber landscape. Built on research-driven, thought leadership and original intellectual property, The Mainstream also curates summits & conferences that convene decision makers to explore how technology reshapes industries and leadership. With a growing presence in India and globally across the Middle East, Africa, ASEAN, the USA, the UK and Australia, The Mainstream carries a vision to bring the latest happenings and insights to 8.2 billion people and to place technology at the centre of conversation for leaders navigating the future.