OpenAI’s No. 2 Executive Fidji Simo Steps Down Due to Extended Medical Leave

Fidji Simo, OpenAI’s No. 2 executive, is stepping down from her full-time role and transitioning to a part-time advisory position, the Wall Street Journal reported on July 9, 2026. In a note to staff, Simo said her ongoing medical leave has proven longer and harder than expected.

Simo joined OpenAI in May 2025 as CEO of Applications — a newly created role reporting directly to CEO Sam Altman that consolidated the company’s business and product operations. In that capacity, COO Brad Lightcap, CFO Sarah Friar, and CPO Kevin Weil all 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.

Simo first disclosed her health situation in April, announcing she was taking medical leave for a relapse of a neuroimmune condition. That same memo revealed Lightcap had moved into a new “special projects” role and that CMO Kate Rouch was leaving the company to focus on cancer recovery. CPO Kevin Weil has since departed as well.

Before OpenAI, Simo served as CEO of Instacart from 2021, leading the company through its 2023 IPO. Prior to that, she spent over a decade at Meta, including running the Facebook app.

Her departure leaves Altman searching for a successor at a difficult moment. OpenAI is eyeing a possible IPO and working to close a gap with Anthropic in the enterprise market. Simo had been seen as a likely candidate for expanded responsibility once OpenAI went public. She was primarily focused on growing OpenAI’s consumer business, though ChatGPT’s growth cooled late last year, missing internal revenue targets and pushing the company toward coding tools — an area where it currently trails Anthropic.