Google has appointed Noam Shazeer, the ex-head of the startup Character.AI and a former long-time Google researcher, as co-lead of its AI models. Shazeer will join Jeff Dean and Oriol Vinyals in leading the Gemini project, a suite of AI models developed by DeepMind, Google’s AI division. These models are set to enhance products like Google Search and Pixel smartphones.

Shazeer, who recently returned to Google after founding Character.AI in 2021, was brought back with a significant investment from the tech giant, which also included a licensing agreement with Character.AI. In response to his new role, Shazeer expressed enthusiasm about rejoining Google in an email seen by Reuters, calling the opportunity to work with the team “the best on earth.”

Shazeer initially joined Google in 2000 and contributed to a pivotal 2017 research paper that helped spur the current AI revolution. Character.AI, which leverages advancements from that paper, has raised $193 million and was valued at $1 billion last year.

Despite discussions about investing hundreds of millions into Character.AI, Google opted instead to bring Shazeer and other key employees back in-house. This strategy mirrors similar efforts by Amazon and Microsoft to attract top AI talent, amidst growing regulatory scrutiny on major tech companies. Notably, Google is currently facing legal challenges, including a recent antitrust ruling against its search engine practices.