Alexandr Wang’s Scale AI just inked a $14.3 billion investment deal with Meta, which transitions the 28-year-old out of his CEO position at the startup he cofounded with fellow billionaire and estranged business partner Lucy Guo.

Wang announced Thursday on X that he’s leaving Scale AI to join Meta as part of an agreement that gives CEO Mark Zuckerberg’s tech company a 49% stake in the startup. Wang became the world’s youngest self-made billionaire at age 24, just five years after dropping out of college and creating the San Francisco–based company. Now, his estimated net worth is $3.6 billion.

“I started this company right out of freshman year of MIT and never looked back,” Wang wrote in his memo to Scale AI employees on Thursday. “I wouldn’t change a minute of it.”

Wang will continue to serve as a director on the company’s board while working on “superintelligence efforts” for Meta, a Scale AI spokesperson told CNBC, but did not elaborate on specifics. In his note, Wang said he would poach a few “Scalien” employees to take with him to Meta, but did not name them.

In the interim, Scale’s board and Wang decided to appoint chief strategy officer Jason Droege as a temporary CEO. Prior to joining Scale AI in August 2024, Droege was a venture partner at Benchmark and an Uber vice president, according to his LinkedIn.