Google Gemini Co-Lead Noam Shazeer Defects to OpenAI Ahead of IPO

The architect of modern AI switches sides

Noam Shazeer, Google's VP of Engineering and co-lead of its flagship Gemini AI models, announced on June 18 that he is leaving the company to join OpenAI — the maker of ChatGPT that confidentially filed for an IPO earlier this month.cnbc +1 "I'm excited to share that I'll be joining OpenAI," Shazeer wrote on X, adding that it had been "a difficult decision to move on."cnbc The departure carries enormous symbolic weight: Shazeer is a co-author of the 2017 paper "Attention Is All You Need," which introduced the Transformer architecture that underpins virtually every large language model in use today.the-decoder +1

A $2.7 billion hire exits in under two years

Google paid approximately $2.7 billion in August 2024 to bring Shazeer back from Character.AI, the AI chatbot startup he co-founded after leaving Google in 2021.reuters +1 He had originally departed after Google declined to aggressively pursue a chatbot product he and co-founder Daniel De Freitas had championed internally.cnbc Upon his return, Google appointed him to co-lead Gemini development, and he was credited as a key figure in closing the gap on OpenAI's ChatGPT.reuters The abrupt exit — less than 24 months after that landmark deal — underscores how fragile even the most expensive talent arrangements have become in the AI era.

OpenAI lands its biggest recruit ahead of IPO

OpenAI CEO Sam Altman called Shazeer "one of the people I have most wanted to work with since the very beginning of OpenAI," saying the partnership was "only 10 years in the making."benzinga The hire arrives as OpenAI prepares for what could be one of the largest technology listings in years, having confidentially filed its S-1 with the SEC in early June at a valuation of up to $1 trillion.tech-insider The company reported approximately $13 billion in revenue against a net loss of roughly $39 billion in 2025.yahoo +1 Adding one of the most celebrated researchers in the field is seen as a bid to shore up OpenAI's technical credibility ahead of intense investor scrutiny of those numbers.

A widening rift in AI talent

The move tracks a broader pattern of high-profile researchers switching companies. Andrej Karpathy's earlier move to Anthropic had been described as the biggest AI talent story of 2026 before this week's announcement.the-decoder Google told Reuters it was "grateful for Noam's meaningful contributions over the years," a statement that offered no detail on how the company plans to fill the void at the top of Gemini.reuters The timing is particularly sharp: Shazeer's departure came just weeks after Alphabet's annual I/O developer conference, where Google unveiled Gemini 3.5 Flash and the Gemini Spark AI agent — products built under his leadership.cnbc +1