Summary
On June 18, 2026, Noam Shazeer announced on X that he is leaving Google to join OpenAI. Shazeer is a co-author of the 2017 paper "Attention Is All You Need," the foundational work introducing the Transformer architecture that underpins virtually every major large language model currently deployed. He had served as a vice president of engineering at Google and co-lead of its Gemini model family since returning to the company through an approximately $2.7 billion transaction to reacquire him from Character.AI, the conversational AI startup he had co-founded after an earlier departure from Google in 2021. Sam Altman confirmed the hire, writing that Shazeer was "one of the people I have most wanted to work with since the very beginning of OpenAI." Shazeer's role at OpenAI was not disclosed in the announcement. OpenAI was at the time conducting a confidential IPO registration process with the SEC.
What Happened
Noam Shazeer's career through 2026 traces the core institutions of the large-language-model era. He spent approximately two decades at Google across two tenures, working on search, recommendations, and neural language models. In 2017, as part of the Google Brain team, he co-authored "Attention Is All You Need" (Vaswani et al., 2017) alongside Ashish Vaswani, Niki Parmar, Jakob Uszkoreit, Llion Jones, Aidan Gomez, Łukasz Kaiser, and Illia Polosukhin. That paper introduced the Transformer architecture, which displaced prior sequence-to-sequence approaches and became the architectural foundation for GPT, BERT, Claude, Gemini, and the broader generation of language models that followed. Shazeer was also the primary author of several influential follow-on architectural contributions, including the Mixture-of-Experts gating mechanism used in many modern large models.
In 2021, Shazeer left Google to co-found Character.AI, a conversational AI platform. Google moved to reacquire him: in 2024, Google structured a licensing and employment arrangement with Character.AI valued at approximately $2.7 billion under which Shazeer and a portion of Character.AI's talent returned to Google. At Google, he took the role of vice president of engineering and co-led the Gemini model family alongside others in the Google DeepMind structure.
On June 18, 2026, Shazeer posted on X: "I'm excited to share that I'll be joining OpenAI and look forward to working with the exceptional team there," calling the departure from Google "a difficult decision." Sam Altman responded publicly: "noam is one of the people I have most wanted to work with since the very beginning of openai. only took 10 years. i think it will be worth the wait!" The Information reported that OpenAI informed staff of the hire on June 18. No specific role title or team assignment for Shazeer at OpenAI was disclosed in the announcement or in subsequent reporting as of the date of this record.
The departure is notable in the context of a broader pattern. As of mid-2026, seven of the eight co-authors of "Attention Is All You Need" have left Google. The seven departures founded or joined Cohere, Essential AI, Sakana AI, Inceptive, NEAR Protocol, and now OpenAI, among other organizations. Only one co-author had remained at Google as of this writing.
The announcement came approximately ten days after OpenAI filed a confidential draft registration statement with the SEC on June 8, 2026, initiating the formal IPO process. OpenAI at the time was targeting a workforce expansion from approximately 4,500 to 8,000 employees and was building out its research capacity ahead of the public offering.
Why It Matters
Shazeer's move to OpenAI is the most consequential single talent departure from Google's AI research organization in the period covered by The Ledger. His co-authorship of the Transformer paper makes him among the small group of individuals whose direct technical contributions can be traced to virtually every frontier language model currently in production. His departure also represents the third time he has left a major organization — Google, then Character.AI, now Google again — for a competitor, suggesting that individual research autonomy and mission alignment are factors that financial arrangements have not consistently resolved.
For OpenAI, the hire accomplishes two things simultaneously: it adds foundational architectural expertise at a moment when the company's research focus has shifted toward agentic and reasoning-capable systems, and it removes a key technical resource from the Gemini effort at Google. OpenAI's stated goal of growing to 8,000 employees before or shortly after the IPO reflects a broader scaling of research and engineering capacity, and Shazeer's arrival signals that the company can attract top-tier technical talent even at its current scale and valuation.
What remains unknown: what specific research or engineering problem Shazeer will be assigned to at OpenAI, whether his arrival marks the beginning of a broader exodus from Google's Gemini team, and whether the Character.AI licensing terms that governed his 2024 return to Google impose any constraints on his ability to work at a direct competitor. None of these questions had been addressed in public reporting as of this record.
His exact X post URL was not resolvable through public search at the time of this record; the primary_recording source above references his profile. The post text is confirmed across multiple independent outlets.
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