"Today, as the world undergoes significant change, as the race for AI accelerates, and as Meta prepares for its next chapter, it is time to create space for others to pursue the work," she wrote in a social media post.
Meta — the parent company of Facebook and Instagram — didn't immediately respond to an emailed request for comment about the move. Pineau didn't announce a replacement.
Based in Montreal, where she is also a computer science professor at McGill University, Pineau has been the face of Meta's “open-source” approach to building AI systems, such as its flagship large language model called Llama, in which core components are publicly released for others to use or modify.
Her announcement comes ahead of the company's debut of a new LlamaCon AI conference on April 29.
In 2023, she began directing Meta's AI research division, formerly known as Facebook AI Research, which had been founded a decade earlier by a group that included pioneering AI researcher Yann LeCun. LeCun stepped down as the group's director in 2018 but remains Meta's chief AI scientist.