OpenAI Rehires Former AI Safety Chief Lilian Weng After Thinking Machines Exit

Thinking Machines co-founder Lilian Weng has stepped down from the AI startup, citing health concerns, and will return to OpenAI to lead a new internal research team focused on recursive self-improvement, the company confirmed.

Weng announced her departure in an internal Slack message that she also shared publicly on X, saying she could no longer keep up with the demands of startup life after months of considering the decision.

"I don't feel I'm able to continue at the pace a startup requires," Weng wrote. "After thinking about it for several months, I ultimately have to admit that the amount of consistent stress and workload have pushed me beyond what my health can sustain physically."

OpenAI confirmed that Weng is rejoining the company, where she previously served as vice president of AI Safety Research. According to an OpenAI spokesperson, she will now lead a top-level team responsible for accelerating internal research and supporting work on recursive self-improvement, an area focused on AI systems that can iteratively improve their own capabilities.

The role marks a shift from her previous position overseeing AI safety research. Instead, Weng will head a cross-research effort centered on one of OpenAI's long-term research initiatives.

The move comes only days after Weng announced she was leaving Thinking Machines, the startup co-founded by former OpenAI CTO Mira Murati. While Weng attributed her departure to the sustained workload and stress of building a startup, OpenAI did not indicate when discussions about her return began.

Murati publicly supported Weng's decision following her announcement. "We'll miss you, it's been wonderful building Thinky together. I'm glad that you're putting your health first. Thank you for everything," Murati wrote on X.

It remains unclear whether Murati knew Weng would soon return to OpenAI when she posted the message.

Weng's return also places a former AI safety executive at the center of OpenAI's recursive self-improvement research. According to the company, the team she will lead is intended to accelerate internal research efforts across multiple groups rather than operate as part of the safety organization she previously managed.

Neither Thinking Machines nor OpenAI disclosed additional details about the transition beyond Weng's public statement and OpenAI's confirmation of her new role.

This analysis is based on reporting from TechCrunch.

Image courtesy of Business Insider/AP.

This article was generated with AI assistance and reviewed for accuracy and quality.