Uber’s new head of its AI labs has stepped down from his role

The director of Uber’s artificial intelligence lab, Gary Marcus, has stepped down from his role after a little more than three months. Marcus made the announcement on Facebook, adding that he was starting a new job at Uber as “special adviser for AI.”

Marcus, who will no longer be an Uber employee even as special adviser, joined the company in December when the ride-hail company acquired the AI and machine learning startup he co-founded in 2015, Geometric Intelligence. As part of the acquisition, the company started and put Marcus in charge of its AI lab.

Axios first reported his departure.

Other than Marcus, the remaining 14 members of the startup will stay at the company along with Marcus’s co-founder Zoubin Ghahramani.

It’s unclear why Marcus is stepping down so quickly. But he is one in a slew of top engineers who have recently departed the company.

One day after Uber acquired Geometric Intelligence and put Marcus in charge of all artificial intelligence and machine learning at the company, Danny Lange announced that he was leaving the company to join Unity Technologies. Lange, a big name in the industry, headed up the company’s machine learning team for more than a year.

At around the same time, Uber’s self-driving arm — called the Advanced Technology Group — lost three of its top engineers that the company poached away from Carnegie Mellon.

In February, the former director of the ATG, Raffi Krikorian, also stepped down from his role. Last week, famed security engineer Charlie Miller announced he was leaving the company and has since joined Didi’s self-driving efforts.

Many of the engineers who left Uber have since started their own or joined competing self-driving companies.

This article originally appeared on Recode.net.