OpenAI CFO Sarah Friar is looking to reassure its investors that the richly valued artificial intelligence startup is still in a strong position and is poised to close a big funding round soon, despite losing top talent this week.

In an email to OpenAI’s investors seen by CNBC, Friar addressed the departure of Chief Technology Officer Mira Murati, who announced her departure on Wednesday. Later that day, Sam Altman said two top research executives, Bob McGrew and Barret Zoph, were also leaving.

“I wanted to personally reach out following the news of Mira’s departure from OpenAI,” Friar wrote in the letter, which was viewed by CNBC. “While leadership changes are never easy, I want to ensure you have the full context.”

Friar added that, “We are incredibly proud of everything she’s helped build,” and said the San Francisco-based company still has a “talented leadership bench” to compete.

OpenAI, which is backed by Microsoft and recently partnered with Apple on its AI for iPhones, is in the midst of closing a $6.5 billion funding round, which should value the company at roughly $150 billion, according to sources familiar with the matter. Thrive Capital is leading the round, and plans to invest $1 billion, according to sources.

Friar said in the email that the funding round was oversubscribed and would close by next week. She said the team plans to host a series of calls with investors to introduce the group to key leaders from product and research teams.

“Collectively, we remain laser-focused on bringing AI to everyone and building sustainable revenue models that fuel our operations and deliver value to our investors and employees,” Friar wrote. The company is “excited for you to be with us as we enter our next chapter,” she wrote.

OpenAI declined to comment on the email.

Murati’s departure comes after six and a half years at the company. She briefly served as interim CEO last year after the board of directors abruptly fired Altman. When Altman was quickly reinstated, Murati returned to the role of CTO.

The company was already dealing with the loss of key executives. Co-founder John Schulman and safety chief Jan Leike left to join rival Anthropic. Co-founder Ilya Sutskever left to start another AI company , while another founder, Greg Brockman, is on a leave of absence.

Friar said Mark Chen will step into the role of of senior vice president of research, and leaders like Kevin Weil, who joined from Meta, and Srinivas Narayanan are the “right people to keep pushing the boundaries of innovation.”

Friar was formerly CEO of Nextdoor, and before that CFO at Block, formerly Square.

Also on Thursday, at an all-hands meeting, Altman denied that there are plans for him to receive a “giant equity stake” in the company, calling reports of such a development “just not true,” according to a person who was in attendance.

Altman and Friar both said at the meeting, conducted by video, that investors have raised concerns about Altman not having equity in the company that he co-founded almost nine years ago, said the person, who asked not to be named because the gathering was only for employees.

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