After a three-month absence, Greg Brockman, co-founder of OpenAI, returns to the company.

• After taking a sabbatical that started in August, Greg Brockman, co-founder of OpenAI, has returned to the startup.
• More than a month after OpenAI closed its latest funding round at a valuation of $157 billion, Brockman's return.
• The company has faced challenges with executive departures and controversy surrounding its transition to a for-profit model.

OpenAI co-founder Greg Brockman has returned to the company as president, three months after announcing he would take a sabbatical "through end of year." On Tuesday, he posted on X that the "longest vacation" of his life was complete and that he was "back to building OpenAI."

More than a month after OpenAI closed its latest funding round at a valuation of $157 billion, Brockman's return comes with an increasing number of executives departing and the company facing heightened controversy surrounding its upcoming conversion to a for-profit structure and its decision to shutter certain safety teams.

In late September, OpenAI Chief Technology Officer Mira Murati, research chief Bob McGrew, and research vice president Barret Zoph announced their departures from the company. In May, OpenAI co-founder Ilya Sutskever and former safety leader Jan Leike left, with Leike joining rival Anthropic. Co-founder John Schulman also departed for Anthropic in August. Last week, Lilian Weng, OpenAI's vice president of research and safety, announced her departure after seven years at the company.

Brockman and Altman have been close allies since the company's inception in 2015, with Brockman serving as chief technology officer and Altman as CEO.

After Altman's temporary removal, Brockman posted on X that he had resigned. He also stated in a post at the time that both he and Altman were "shocked and saddened by what the board did today."

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