Fidji Simo Steps Down From Full-Time OpenAI Role Amid Other Executive Departures

Fidji Simo is stepping down from her full-time role at OpenAI and will transition to a part-time advisory position. Simo announced the change in a staff note on Thursday, citing ongoing medical leave that has lasted longer than expected. She first disclosed her health issues in April, when she took leave for a relapse of a neuroimmune condition.

Simo joined OpenAI’s board of directors in 2024 and became CEO of Applications in May 2025. The role consolidated the company’s business and product operations and reported directly to Sam Altman. COO Brad Lightcap, CFO Sarah Friar, and CPO Kevin Weil began reporting to her after the appointment.

Altman stepped back to focus on research, compute, and safety. Lightcap moved into a new special projects role in April. CMO Kate Rouch left OpenAI in April to focus on cancer recovery. Kevin Weil has since left the company.

Simo previously served as CEO of Instacart from 2021 through its 2023 IPO and spent more than a decade at Meta, including running the Facebook app. On the same day, OpenAI launched its GPT-5.6 family of models named Sol, Terra, and Luna, along with a new agent called ChatGPT Work designed for multistep office tasks.

TechCrunch reported that OpenAI was most recently assigned an $852 billion valuation.

Sam Altman posted on X that he was sad about the departure and grateful for Simo’s contributions and friendship. Simo came to OpenAI after leading Instacart through its public listing and earlier roles at Meta.