Fidji Simo, the second-highest executive at OpenAI, is resigning from her full-time position, according to recent reports.
In a message to staff on Thursday, Simo explained that her medical leave has been more prolonged and challenging than she anticipated, leading her to shift to a part-time advisory role. She became a member of OpenAI’s board in 2024 and joined the company as CEO of Applications in May 2025, in a newly established position that centralized the organization’s business and product functions under Sam Altman.
Her appointment also led to a significant restructuring in the company’s reporting lines: COO Brad Lightcap, CFO Sarah Friar, and CPO Kevin Weil began reporting directly to her, while Altman redirected his focus toward research, computing, and safety initiatives.
Simo initially revealed her health challenges in April, announcing her medical leave due to a relapse of a neuroimmune disorder. In the same communication, she mentioned Lightcap’s transition to a new role focused on special projects and noted that CMO Kate Rouch would be leaving to concentrate on cancer recovery. Since then, Weil has also exited the company.
Before her time at OpenAI, Simo was the CEO of Instacart, leading the business through its initial public offering in 2023. Prior to that, she spent over ten years at Meta, where she managed the Facebook app.
Simo’s decision to move to a part-time position introduces a leadership gap at a critical time for OpenAI, which is considering a potential public offering. She had been perceived as a strong candidate for greater responsibilities in anticipation of this transition, thus creating a significant void for Altman to fill.
Simo primarily concentrated on expanding OpenAI’s consumer sector. However, the growth of ChatGPT slowed down significantly last year, resulting in the company failing to meet its internal revenue goals. This situation compelled OpenAI to shift its emphasis towards coding tools, an area where it has been lagging behind competitor Anthropic.
Following the initial report, Simo shared her announcement on social media, to which Altman responded, expressing his sadness and gratitude for her contributions and wishing her a smooth recovery.
Simo’s announcement coincided with a busy day for OpenAI, as the company launched its new GPT-5.6 model lineup — Sol, Terra, and Luna — along with a new feature called ChatGPT Work, aimed at managing complex office tasks like creating documents, spreadsheets, and presentations. OpenAI framed both launches as a direct response to competition from Anthropic.
From an external viewpoint, OpenAI’s executive team appears to be somewhat lean for a company recently valued at $852 billion. Besides Altman, key figures like Lightcap, Friar, and co-founder Greg Brockman (who oversees product strategy in Simo’s absence) are part of a smaller team. Recently appointed chief revenue officer Denise Dresser, who has extensive experience from her previous role at Slack and years at Salesforce, could potentially expand her responsibilities within the organization.
Simo’s resignation unfolds against the backdrop of OpenAI’s evolving approach to employee equity. Upon Simo’s arrival in April, the company revised its vesting policies, cutting the waiting period for stock grants from the standard twelve months to six. Later, OpenAI eliminated the waiting period entirely for new hires, allowing equity to vest from day one. This move was framed as a way to empower employees to take risks without the threat of losing equity if they were to depart prematurely, reflecting OpenAI’s aggressive spending approach in an increasingly competitive AI labor market.
The exits mentioned seem unrelated to compensation, as executive equity packages are often customized and carry different vesting conditions.
