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- Fidji Simo is stepping down from her executive role at OpenAI after her medical leave.
- The former Instacart CEO will transition to a part-time advisor role.
- Simo said her chronic illness pushed her to take medical leave three months ago.
Fidji Simo, one of OpenAI's top executives, is stepping down.
Simo, the company's CEO of applications, wrote on X on Thursday that she has decided to leave her full-time role and become a part-time advisor.
Simo went on medical leave three months ago. She said on Thursday that she would focus on recovery amid her long-running chronic illness, which does not have a cure.
"During that time, it became clear that the road to recovery would be much longer and more complex than I had anticipated—and that I needed to focus on it fully," she added.
Simo was diagnosed with postural tachycardia syndrome, or POTS, in 2019. The disorder can cause fainting, intense bouts of dizziness, and an elevated heart rate.
She joined OpenAI in 2025, decamping from her CEO job at Instacart, which she'd steered through an initial public offering. She'd previously worked at Meta, formerly Facebook, for more than a decade.
Simo's role was to turn cutting-edge AI models into a sustainable business. The company poured tens of billions of dollars into its tech, only to find itself trailing rival Anthropic earlier this year for some lucrative enterprise customers. Now, the two companies are nearing trillion-dollar valuations and eyeing IPOs, and the pressure is on to boost revenues.
Simo revealed a strategy shift earlier this year, Business Insider reported, pushing the company to focus on productivity for companies and customers above all else.
"We cannot miss this moment because we are distracted by side quests," Simo told employees at an all-hands meeting, a person familiar with her remarks told Business Insider. The company soon shut down Sora, its video app, and has recently poured resources into the Codex coding tool to compete with Anthropic's Claude Code.
Former colleagues of Simo told Business Insider that they'd seen her as a laser-focused, empathetic, relentless leader skilled in long-term strategy. Simo said she did a "listening tour" to better understand the company and aimed to keep OpenAI's culture feeling like a research lab rather than a nascent tech giant.
As CEO Sam Altman focused on research and computing, Simo said she would drive work on the company's products and commercialization.
In her Thursday post, Simo thanked OpenAI's board, Altman, and company president Greg Brockman for their support, and wrote that her journey with her illness had reinforced her belief in the importance of technology.
Altman wrote on X, "i am 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. this sucks."
Simo was plain in her own post about the toll the illness has taken.
"It has been a jarring experience to spend my days helping build the future while simultaneously navigating a disabling disease that still has no cure," she wrote.
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