In August, Google entered into a $2.7 billion deal AI Character.AI chatbot launch. The official reason? Obtaining a license to use Character technology.

The unofficial reason? According to one Wednesday's Wall Street Journal reportthe consensus within Google is that the tech giant primarily wanted to rehire a former employee who left in 2021 after creating an AI chatbot that Google refused to make public.

The engineer, 48-year-old Noam Shazeer, was one of the first hundreds of employees at Google. He quickly established himself as an AI expert and wrote a paper in 2017 with seven other Googlers called “Attention is all you need” who introduced a new deep learning architecture. This paper has been cited by other researchers more than 100,000 times and placed it as one of the the inventors of modern AI.

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Shazeer claims credit for his contributions: His “About” section on LinkedIn at the time of writing reads, “I have invented much of the current revolution in large language models.”

^{Noam Shazeer. Credit: Winni Wintermeyer for The Washington Post via Getty Images}

In 2021, before the release of OpenAI's ChatGPT, Shazeer was working on AI at Google. He and his colleagues created an AI chatbot that could interact with users in conversation, and they asked Google to demonstrate it to the public. Google declined several times and Shazeer left to start Character, building the startup from 2021 to the present day with over 150 million dollars in financing in one a value of 1 billion dollars since March.

Google's August deal with Character brought Shazeer back into the company as part of it DeepMind Research Teamwho works in AI.

Shazeer made hundreds of millions of dollars as part of the deal, according to the WSJ.

Related: Google co-founder Sergey Brin has returned to the company 'Pretty Much Every Day'. Here's what you're working on.

Other big tech companies have made similar deals recently. At the end of August, Amazon signed a deal to non-exclusively license AI models developed by the AI ​​robotics startup covariant and bring in Covariant's co-founders and some employees.