Mira Murati, OpenAI's chief technology officer, earlier announced her departure from the company.Now, CEO Sam Altman revealed two other executives, Barret Zoph and Bob McGrew, are also leaving.Altman also outlined their replacements in a note to staff.

Mira Murati announced on Wednesday that she's leaving OpenAI, where she was chief technology officer. Now, two other leaders are leaving, according to CEO Sam Altman, who posted a note to OpenAI staff shortly after 5 p.m. Pacific Time on X.

According to Altman, "Barret and Bob" are leaving OpenAI. Those are Barret Zoph, who had served as the company's vice president of research, and Bob McGrew, who was chief research officer.

OpenAI did not immediately respond to a request for comment about the departures. But Zoph confirmed his departure, posting a note to X saying he decided to leave OpenAI. And The Verge's Kylie Robison posted on X that McGrew had left the company.

Read the note Altman posted to X below:

i just posted this note to openai:Hi All–Mira has been instrumental to OpenAI's progress and growth the last 6.5 years; she has been a hugely significant factor in our development from an unknown research lab to an important company.When Mira informed me this morning that she was leaving, I was saddened but of course support her decision. For the past year, she has been building out a strong bench of leaders that will continue our progress.I also want to share that Bob and Barret have decided to depart OpenAI. Mira, Bob, and Barret made these decisions independently of each other and amicably, but the timing of Mira's decision was such that it made sense to now do this all at once, so that we can work together for a smooth handover to the next generation of leadership.I am extremely grateful to all of them for their contributions.Being a leader at OpenAI is all-consuming. On one hand it's a privilege to build AGI and be the fastest-growing company that gets to put our advanced research in the hands of hundreds of millions of people. On the other hand it's relentless to lead a team through it—and they have gone above and beyond the call of duty for the company.Mark is going to be our new SVP of Research and will now lead the research org in partnership with Jakub as Chief Scientist. This has been our long-term succession plan for Bob someday; although it's happening sooner than we thought, I couldn't be more excited that Mark is stepping into the role. Mark obviously has deep technical expertise, but he has also learned how to be a leader and manager in a very impressive way over the past few years.Josh Achiam is going to take on a new role as Head of Mission Alignment, working across the company to ensure that we get all pieces (and culture) right to be in a place to succeed at the mission.Kevin and Srinivas will continue to lead the Applied team.Matt Knight will be our Chief Information Security Officer having already served in this capacity for a long time. This has been our plan for quite some time.Mark, Jakub, Kevin, Srinivas, Matt, and Josh will report to me. I have over the past year or so spent most of my time on the non-technical parts of our organization; I am now looking forward to spending most of my time on the technical and product parts of the company.Tonight, we're going to gather at 575 starting at 5:30 pm. Mira, Bob, Barret, and Mark will be there. This will be about showing our appreciation and reflecting on all we've done together. Then tomorrow, we will all have an all-hands and can answer any questions then. A calendar invite will come soon.Leadership changes are a natural part of companies, especially companies that grow so quickly and are so demanding. I obviously won't pretend it's natural for this one to be so abrupt, but we are not a normal company, and I think the reasons Mira explained to me (there is never a good time, anything not abrupt would have leaked, and she wanted to do this while OpenAI was in an upswing) make sense. We can both talk about this more tomorrow during all-hands.Thank you for all of your hard work and dedication.Sam

This is a developing story. Check back for updates.