By Akanksha Khushi

May 14 (Reuters) - OpenAI co-founder and chief scientist

Ilya Sutskever said on Tuesday he is leaving the ChatGPT maker.

"After almost a decade, I have made the decision to leave

OpenAI," he said in a post on X.

Sam Altman, CEO of the Microsoft ( MSFT )-backed company said Jakub

Pachocki will be the company's new chief scientist.

Pachocki has previously served as OpenAI's director of

research and led the development of GPT-4 and OpenAI Five.

"OpenAI would not be what it is without him," Altman said,

referring to Sutskever.

Ilya Sutskever was removed from OpenAI's board in November

last year, after he joined in the effort to fire Altman but

later signed an employee letter demanding his return.

Altman was fired from the company in November without any

detailed cause, sparking confusion about the future of the

startup but he was soon given back the reins of the company.

Sutskever's exit comes a day after the company said at an

event on Monday that it would release a new AI model called

GPT-4o, capable of realistic voice conversation and able to

interact across texts and images.

Shortly after launching in late 2022, ChatGPT was called the

fastest application ever to reach 100 million monthly active

users. However, worldwide traffic to ChatGPT's website has been

on a roller-coaster ride in the past year and is only now

returning to its May 2023 peak, according to analytics firm

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