Fidji Simo, the second-highest-ranking executive at OpenAI, is transitioning from her full-time position, as reported by The Wall Street Journal.
In a memo to staff issued Thursday, Simo explained that her current medical leave has extended beyond initial expectations and presented greater challenges than anticipated, leading her to shift into a part-time advisory capacity. Simo initially joined OpenAI's board of directors in 2024, and subsequently took on the role of CEO of Applications in May 2025. This newly established position reported directly to Sam Altman and was designed to integrate the company's business and product operations.
Her appointment as CEO of Applications was part of a broader organizational restructuring, which saw Chief Operating Officer Brad Lightcap, Chief Financial Officer Sarah Friar, and Chief Product Officer Kevin Weil begin reporting directly to her. This allowed CEO Sam Altman to dedicate his focus to critical areas such as research, compute infrastructure, and safety initiatives.
Simo first publicly addressed her health challenges in April, announcing a medical leave to manage a relapse of a neuroimmune condition. The same internal communication also revealed that Brad Lightcap had transitioned into a new "special projects" role and that Chief Marketing Officer Kate Rouch was departing the company to concentrate on her cancer recovery. Kevin Weil has also since left the organization.
Prior to her tenure at OpenAI, Simo served as CEO of Instacart since 2021, successfully guiding the company through its initial public offering in 2023. Her extensive career also includes over a decade at Meta, where she notably oversaw the operations of the Facebook app.
Simo's permanent step back necessitates CEO Sam Altman's search for a successor at a pivotal time for OpenAI, as the company explores a potential IPO and intensifies efforts to narrow the enterprise market lead held by Anthropic. She was broadly considered a strong contender for expanded leadership responsibilities following OpenAI's public listing, creating a notable void for Altman to address.
Her primary focus at OpenAI centered on expanding the company's consumer-facing business. However, ChatGPT's growth decelerated in late 2023, failing to meet internal revenue projections. This shift prompted OpenAI to increasingly prioritize coding tools, a segment where it currently lags behind competitor Anthropic.
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