Thinking Machines Co-Founder Quits, Rejoins OpenAI

Lilian Weng, co-founder of Thinking Machines, announced her departure from the startup this week, citing health concerns. She said the consistent stress and workload of startup life pushed her beyond what her health could sustain. Days later, OpenAI confirmed Weng would rejoin the company, where she previously led AI Safety Research. She will head a team focused on recursive self-improvement research. Thinking Machines co-founder Mira Murati publicly supported Weng's decision, though it is unclear if she knew Weng planned to return to OpenAI.