Microsoft has made headlines with the hiring of Sam Altman, co-founder and former number one of OpenAI, who was dismissed from his position at the start-up last Friday. The company’s stock rose 1.6% in early trading and is now trading around 1% after the announcement. In a tweet, CEO Satya Nadella announced that Altman, along with other colleagues, would lead a new artificial intelligence research team within Microsoft.

Altman expressed his excitement on Twitter about joining Microsoft and building something new. He also thanked OpenAI for its partnership with Microsoft and stated that they remain committed to their roadmap for their product. Emmett Shear, the former Twitch boss who has been appointed as OpenAI’s interim number one, also shared his thoughts on social media, stating that he believes OpenAI is one of the most important companies in existence today and that he accepted this position because of his confidence in the company’s leadership team.

These announcements come after a tumultuous weekend for OpenAI, during which its board of directors fired Sam Altman following a deliberative review process. The body concluded that Altman’s communication style was not always blunt, impeding his ability to fulfill his responsibilities and leading to a lack of confidence in his leadership abilities. The board also announced that it no longer had confidence in its ability to lead OpenAI and resigned en masse.