The tech giant Alphabet is facing a significant reshuffling of its artificial intelligence ranks, as several of its most prominent AI veterans depart from Google. This major personnel change has sparked concerns about the leadership of this critical growth sector, just as the competition in the AI space intensifies. Following the news, Alphabet shares fell by more than 5% at one point.

Demis Hassabis, the head of Google DeepMind, is set to transition to the role of chairman of the lab. Meanwhile, long-time AI strategy veteran Jeff Dean will leave the company to launch a startup, taking several key staff members with him. In a blog post on Wednesday, Google announced that Koray Kavukcuoglu, the current Chief AI Architect and a long-time deputy to Hassabis, will be promoted to Senior Vice President. He will take over most of Hassabis's responsibilities and report directly to Alphabet CEO Sundar Pichai.

Hassabis, a co-founder of DeepMind, the pioneering AI research lab acquired by Google in 2014, has been a leading figure in AI technology development. In a statement, he said, "I believe now is the right time to hand over the day-to-day operational responsibilities of Google DeepMind, so that I can have the time and space to focus on the big picture and do my best to help shape the future." As of 12:08 p.m. New York time, Alphabet shares were down more than 4%, trading at $362.31.