UPDATE

Twitter co-founder Jack Dorsey will step down as CEO of the social media platform, the company announced. He will be succeeded by Twitter’s current Chief Technology Officer Parag Agrawal.

Dorsey will remain on the board until his term expires in 2022.

Agrawal has been CTO since 2017 and at Twitter since 2011.

In a letter posted on his Twitter account, Dorsey said he was “really sad…yet really happy” about leaving the company and that it was his decision.

Dorsey has faced several distractions as CEO, starting with the fact that he’s also founder and CEO of the payments company Square. Critics have long complained that the arrangement has divided his attention to Twitter’s detriment.

Twitter shares rose 5% to $49.47 in morning trading after the announcement.

Dorsey became Twitter CEO in 2007, but was forced out the next year. He returned to the role in 2015.

While Twitter has high-profile users like politicians and celebrities and is a favorite of journalists, its user base lags far behind old rivals like Facebook and YouTube and newer ones like TikTok. It has just over 200 million daily active users, a common industry metric.