Mira Murati, chief technology officer of OpenAI, announced Wednesday that she is stepping down from the company after a tenure of six and a half years.

“After much reflection, I have made the difficult decision to leave OpenAI,” Murati wrote in a memo to staff, which she also shared on X. “There’s never an ideal time to step away from a place one cherishes, yet this moment feels right.”

Murati’s exit marks the latest in a series of high-level departures from the Silicon Valley AI startup. Co-founder John Schulman announced last month that he was leaving to join rival Anthropic, following co-founder Ilya Sutskever and former safety chief Jan Leike, who stepped down in May.

Besides her CTO role, Murati also briefly served as interim CEO during last year’s failed attempt to oust Sam Altman.

In her memo, Murati said she is stepping away to “create the time and space to do my own exploration” and emphasized her commitment to ensuring a smooth transition.

She also praised recent company achievements, writing, “Our releases of speech-to-speech and the [latest models] OpenAI o1 mark the beginning of a new era in interaction and intelligence — achievements made possible by your ingenuity and craftsmanship.”

Recently, Bloomberg reported that OpenAI was on the verge of the largest venture capital fundraising round of all time at $6.5 billion. The funding round values OpenAI at $150 billion, up from $86 billion in an earlier round.