xAI Co-Founder Yang Leaves Musk’s Startup After Lyme Diagnosis

Jan. 20, 2026, 7:27 PM UTC

Greg Yang, one of the co-founders of Elon Musk’s startup xAI, is stepping down from the company after being diagnosed with Lyme disease.

Yang will be an informal adviser to the company while focusing on recovery, he said Tuesday in a post on X. Yang, who previously worked at Microsoft Corp., was one of the founding members of Musk’s artificial intelligence startup in 2023.

“Likely I contracted Lyme a long time ago, but until I pushed myself hard building xAI and weakened my immune system, the symptoms weren’t noticeable,” he said in the post. Lyme is an ...

Learn more about Bloomberg Law or Log In to keep reading:

See Breaking News in Context

Bloomberg Law provides trusted coverage of current events enhanced with legal analysis.

Already a subscriber?

Log in to keep reading or access research tools and resources.