In a staff note Thursday, Simo said her ongoing medical leave has proven longer and harder than expected, and that she'll transition to a part-time advisory role instead. Simo joined OpenAI's board of directors in 2024 and joined OpenAI in May 2025 as CEO of Applications, then a newly created role reporting directly to Sam Altman that consolidated the company's business and product operations. Her appointment came with a broader reporting shift: COO Brad Lightcap, CFO Sarah Friar, and CPO Kevin Weil all began reporting to her, while Altman stepped back to focus on research, compute, and safety. Simo first disclosed her health issues in April, when she announced she was taking medical leave for a relapse of a neuroimmune condition; that same memo publicly announced that Lightcap was moving into a new 'special projects' role and that CMO Kate Rouch was leaving the company to focus on cancer recovery. Weil has since left the company, too. Simo's decision to step back permanently leaves...
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