The news that Dorsey was expected to depart the executive role was first reported by CNBC, and Dorsey confirmed in a tweet that he had resigned on Monday. Bret Taylor will take over as new chairman of the board, and Dorsey will serve on the board through May. 

“I believe it’s critical a company can stand on its own, free of its founder’s influence or direction,” Dorsey wrote in an email to the entire company Monday morning, which he then tweeted. 

Twitter stock soared more than 11% following reports of Dorsey’s resignation.

Besides serving as the CEO of Twitter, Dorsey is also the CEO of Square, a digital payment service. His role at that company has been a source of friction with some Twitter investors. Last year, Elliott Management attempted to oust Dorsey as CEO. 

Though he was a founder of Twitter, Dorsey’s history with the company hasn’t been a smooth one. He initially ran the company, but his management style was widely criticized, and in 2008 he was pushed out by the company’s board. 

Two years later, Dorsey reportedly launched a whisper campaign among Twitter’s board and employees to get then-CEO Evan Williams fired, and he returned to the company.

Williams was replaced with Dick Costolo later that year, and Dorsey moved from a passive board member to executive chairman. By 2015, he was CEO again.

The past few years have been rocky for Twitter. The company has been criticized for verifying white supremacists and providing a space for aggressive and hateful discourse. It has also faced criticism from prominent Republicans for being biased against conservatives. After the Jan. 6 Capitol riot, Twitter banned former President Donald Trump from the platform “due to the risk of further incitement of violence.”  

“I want you all to know that this was my decision and I own it. It was a tough one for me, of course. I love this service and company…and all of you so much,” Dorsey wrote in his email. “I’m really sad…yet really happy.”