Fidji Simo Steps Down From Full-Time Role as OpenAI CEO of Applications

Fidji Simo is stepping down from her full-time role as CEO of Applications at OpenAI and will continue with the company as a part-time adviser. Simo announced the move on Thursday in a staff note. She said her medical leave for a relapse of a neuroimmune condition has proven longer and harder than expected.

After her appointment, COO Brad Lightcap, CFO Sarah Friar, and CPO Kevin Weil reported to her. The announcement came the same day OpenAI launched the GPT-5.6 family of models and a new agent called ChatGPT Work.

OpenAI was most recently assigned an $852 billion valuation. Simo joined OpenAI's board of directors in 2024. She previously served as CEO of Instacart since 2021, leading the company through its 2023 IPO, and spent over a decade at Meta, including running the Facebook app.

Sam Altman posted on X that he was 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. we all wish her the best for a speedy recovery.