Sam Altman will return to OpenAI’s Board of Directors, the exclusive group with ultimate control over the ChatGPT developer, first reported by The Information on Friday. The decision comes just over four months after the board mysteriously fired Altman, causing more than 700 OpenAI employees to revolt and threaten to leave the company.

An investigation into the November near-disaster by the external law firm WilmerHale has concluded, according to an OpenAI blog post on Friday. The investigation found that Sam Altman was fired due to a “loss of trust between the prior Board and Mr. Altman.” WilmerHale says the firing did not arise out of concerns for product safety, security, pace of development, or finances.

Altman is joined by three new board members: Sue Desmond-Hellmann, former CEO of the Bill and Melinda Gates Foundation; Nicole Seligman, former President of Sony, and Fidji Simo, CEO of Instacart. Notably, all three new members are women, joining an all-male board, but lack the research background of OpenAI’s previous directors.

OpenAI’s board has an unusual mandate to benefit humanity over shareholders. The group ultimately decides when the startup has achieved an ultra-powerful AI known as artificial general intelligence or AGI.

As OpenAI’s CEO returns to the Board of Directors, there are still unanswered questions about what soured his relationship with the prior board. Ilya Sutskever, Tasha Mccauley, and Helen Toner resigned from their board seats in November after firing Altman.

OpenAI Chief Scientist and co-founder Ilya Sutskever is still in talks about remaining at the company, according to The Information’s report. Sutskever has rarely been heard from in the last four months, with the exception of a letter he co-authored to Elon Musk earlier this week.

One speculation about Altman’s firing related to the CEO’s numerous side projects, which most recently include a $7 trillion chip-building initiative. OpenAI’s board issued a new policy on Friday to prevent potential conflicts of interest.