Transformer Co-Inventor Noam Shazeer Leaves Google for OpenAI

Noam Shazeer, co-author of the Transformer paper and Gemini co-lead, has left Google to join OpenAI as Lead for AI Architecture Research.

AI Tutorials · 21 June 2026 · 2 min read

Quick answer

Noam Shazeer, co-author of the landmark 2017 'Attention Is All You Need' paper that introduced the Transformer architecture, has left Google to join OpenAI as Lead for AI Architecture Research. Google had paid $2.7 billion just two years ago to bring Shazeer back from Character AI, making this one of the most significant talent moves in AI history.

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Transformer Co-Inventor Noam Shazeer Leaves Google for OpenAI

The man who helped invent the technology behind every major AI assistant is switching sides. Noam Shazeer, co-author of the 2017 Transformer paper and co-lead of Google’s Gemini models, has left Google to join OpenAI as its Lead for AI Architecture Research.

The move is a major talent win for OpenAI — and a painful loss for Google.

Why This Matters

In 2017, Shazeer and seven colleagues at Google published “Attention Is All You Need,” the paper that introduced the Transformer architecture. That single idea became the foundation for ChatGPT, Gemini, Claude, and essentially every modern AI model. It is not an exaggeration to say the current AI boom traces directly back to this work.

Shazeer left Google in 2022 to co-found Character AI, a startup focused on conversational AI characters. Google wanted him back badly enough to pay $2.7 billion in 2024 to acquire parts of Character AI’s team and technology, bringing Shazeer back as VP of Engineering and co-lead of Gemini.

Now, less than two years later, he is leaving again — this time for Google’s biggest rival.

What He Will Do at OpenAI

At OpenAI, Shazeer will lead AI Architecture Research, overseeing the fundamental design of the company’s next generation of models. The hire comes as OpenAI prepares for its anticipated IPO and continues to compete with Google and Anthropic for dominance in frontier AI.

The timing is notable. Google’s Gemini 3.5 Pro is expected to launch publicly before the end of June, while OpenAI continues to build on its GPT series. Having the co-inventor of the Transformer leading architecture research gives OpenAI a significant edge in designing what comes next.

What This Means for You

For everyday AI users, this will not change anything overnight. But talent moves at this level shape the products you will use a year from now. The AI tools that improve fastest are built by the strongest research teams — and OpenAI just got considerably stronger.

If you are interested in how the competition between AI companies shapes the tools available to you, this is a story worth watching.

Frequently asked questions

Who is Noam Shazeer?

Noam Shazeer is a computer scientist who co-authored the 2017 paper 'Attention Is All You Need,' which introduced the Transformer architecture. Transformers are the foundation of virtually every modern AI model, including GPT, Gemini, and Claude. He was most recently a VP of Engineering and co-lead of Google's Gemini models.

Why did Noam Shazeer leave Google for OpenAI?

The exact reasons have not been publicly detailed. Shazeer will serve as Lead for AI Architecture Research at OpenAI, overseeing the fundamental design of advanced AI models. The move comes ahead of OpenAI's planned IPO.

What is the Transformer architecture?

The Transformer is a type of neural network architecture introduced in 2017 that processes text by paying 'attention' to relationships between all words simultaneously. It replaced older sequential approaches and became the foundation for every major AI assistant, including ChatGPT, Gemini, and Claude.

How does this affect Google's AI efforts?

Losing Shazeer is a significant blow for Google, especially since the company paid $2.7 billion in 2024 to bring him back from Character AI. However, Google still has a deep bench of AI researchers and its Gemini 3.5 models are expected to launch soon.