Lilian Weng leaves Thinking Machines to rejoin OpenAI as head of internal research
Her move shifts a prominent AI-safety researcher from a startup environment to OpenAI, potentially reshaping internal safety priorities and intensifying lab talent competition.
At a glance
- Left Thinking Machines citing health reasons, sharing a Slack message and an X post
- OpenAI confirms she will rejoin and lead a top-level team to accelerate internal research, with cross-research on recursive self-improvement
- Previously served as OpenAI's VP of AI Safety Research
- Techmeme notes The Information reported she co-founded Thinking Machines Lab and left TML over workload-related health concerns before returning to OpenAI
The story
Lilian Weng, co-founder of Thinking Machines, announced this week that she would step down from her role, citing health issues. In a Slack message she shared on X, she wrote, “I don’t feel I’m able to continue at the pace a startup requires,” adding that the amount of consistent stress and workload have pushed her beyond what her health can sustain.
OpenAI said she would rejoin the company, where she previously served as the VP of AI Safety Research. OpenAI’s spokesperson said Weng will lead a top-level team focused on accelerating OpenAI’s internal research, and that the team will support cross-research work on recursive self-improvement.
TechCrunch notes that the move could be read as contradictory to Weng’s statements about the impact of working at a fast-paced startup on her health, though she is unlikely to face as much direct pressure while working at a bigger company.
Mira Murati responded to Weng’s X post with support for her decision to focus on her health, writing, “It is a hard and sad decision. I shared this message with folks at Thinky. Thank you all for the time together♥️ Just as the last sentence in my message: The future worth building is human.”
Techmeme’s coverage cites The Information reporting that Weng is returning to OpenAI after announcing earlier this week she was leaving Thinking Machines Lab over workload-related health concerns (Lilian Weng, a researcher who cofounded AI startup Thinking Machines Lab alongside former OpenAI Chief Technology Officer Mira Murati)