OpenAI's new CFO, Sarah Friar, emailed investors on Thursday just after CTO Mira Murati and two other top executives left.Kevin Mazur/Getty Images for TIME and Brian Lawless - Pool/Getty ImagesOpenAI CFO Sarah Friar emailed investors the day after three top execs suddenly left, per CNBC.Friar sought to soothe investor worries, saying the firm is still "laser-focused" on AI that can bring them returns.OpenAI has been seeking a $150 billion valuation, and Friar said its first investing round is oversubscribed.OpenAI's chief financial officer, Sarah Friar, is trying to assure investors that the company is still in good hands despite the sudden exit of three top executives, according to an email reported by CNBC.The outlet's Kate Rooney cited an email from Friar to OpenAI investors on Thursday night, a day after the firm saw the departure of its chief technology officer, Mira Murati.Two other leaders, VP of Research for Post Training Barret Zoph and Chief Research Officer Bob McGrew, are also leaving.Friar's email spoke of their exits directly, saying that even after the switch-up, OpenAI still fields a "talented leadership bench.""While leadership changes are never easy, I want to ensure you have the full context," she wrote, per CNBC.She also told them that the promise of their returns was still airtight."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," she wrote.Friar herself is a relatively new hire, joining the firm in June after helming Nextdoor.OpenAI has been trying to raise a valuation of more than $150 billion.