Fidji Simo is stepping down from her full-time role as CEO of AGI Deployment at OpenAI following a three-month medical leave, the company said on Wednesday. Simo announced the transition in a post on X, saying she would remain with the organisation in a part-time advisory capacity. She said the road to her recovery would be much longer and more complex than she had anticipated and that she needed to focus on it fully.
Simo disclosed that she went on medical leave three months ago after a severe exacerbation of a chronic illness she has lived with for seven years. She was diagnosed with Postural Orthostatic Tachycardia Syndrome, known as POTS, in 2019. During her absence, OpenAI President Greg Brockman took over product responsibilities. Sam Altman said in a post on X that he is grateful for Simo's contributions to the company and for her friendship [Source: Reuters].
Simo joined OpenAI in May 2025 as CEO of Applications, a newly created role reporting directly to Altman that consolidated the company's business and product operations. In that position, COO Brad Lightcap, CFO Sarah Friar, and CPO Kevin Weil reported to her, while Altman stepped back to focus on research, compute, and safety. She had also joined OpenAI's board of directors in 2024.
In April 2026, Simo announced her medical leave of absence alongside a set of leadership changes, disclosing a worsening neuroimmune condition. The same memo detailed that Lightcap would transition to a new role focused on special projects reporting directly to Altman, with Chief Revenue Officer Denise Dresser taking over most of Lightcap's responsibilities. OpenAI's marketing chief Kate Rouch also stepped down in that announcement to focus on her own cancer recovery. Simo's current departure flows from that same leave, as her recovery has proven longer and more complex than initially anticipated.
Prior to OpenAI, Simo served as CEO of Instacart, where she took the company public and helped break the longest tech IPO drought in three decades. Before that, she spent more than a decade in leadership roles at Meta, acting as the head of Facebook from 2019 until 2021. Her departure comes as OpenAI confidentially filed for an IPO last month, a week after rival Anthropic did the same, though the company has not offered a timeline for a public market debut and is reportedly putting off those plans until at least next year.
Sources: Bloomberg, Wired, The Verge, Reuters, CNBC, Wall Street Journal, TechCrunch