Lilian Weng rejoins OpenAI from Thinking Machines

Lilian Weng, co-founder of AI startup Thinking Machines Lab, stepped down from her role citing health issues caused by the intense pace of startup life. Within days, OpenAI announced that Weng would rejoin the company, where she previously served as VP of AI Safety Research. At OpenAI, she will lead a top-level team focused on recursive self-improvement, an area of AI research aimed at enabling systems to improve themselves. Weng's departure leaves only Mira Murati and Dan Schulman from the original six founding members of Thinking Machines Lab, as other co-founders Barret Zoph, Luke Metzger, and Andrew Tullock had previously left, with Zoph and Metz returning to OpenAI earlier this year. The move highlights the competitive talent market in AI and the physical toll of startup leadership. OpenAI has been actively recruiting talent from other companies, including recent hires from Netflix, Uber, Salesforce, and others.