Michael Seibel announced late Wednesday on X that after greater than 12 years on the famed accelerator Y Combinator, he’s transitioning to a “accomplice emeritus” function.

Y Combinator CEO Garry Tan shared the information individually in an organization blog post, highlighting Seibel’s lengthy historical past with the outfit. Seibel first joined YC as a founder, going by way of this system twice — as soon as with the streaming startup Justin.TV and later with the streaming app Socialcam. Seibel later served as a bunch accomplice, managing director, and CEO of the YC accelerator.

Notably, Seibel had already stepped again right into a much less operational group accomplice function lately. In a YC weblog put up final yr, he wrote that he was able to “hand over my management duties,” with the transition turning into “efficient” after the accelerator’s winter batch of startups accomplished this system.

A dozen years is an extended tenure for anybody, however Seibel’s departure could have been set in movement as early as 2022, when Tan was appointed President and CEO. The transfer reportedly stunned some YC workers — partly as a result of Tan was working a separate enterprise fund on the time exterior of YC, but additionally as a result of they believed Seibel to be subsequent in line for the function.

We’ve reached out to Seibel for remark. Within the meantime, he shared in his X put up that after taking this coming summer season to chill out, he’s wanting to “assist authorities higher serve its residents.” He added, “Authorities was the eagerness of my youth, and I’m excited to reengage.” Seibel signed off by thanking Y Combinator founders Paul Graham and Jessica Livingston for “altering my life.”

The information comes roughly two weeks earlier than YC’s spring batch of founders kick off their very own tour of responsibility; this system will run from April by way of June.