Twitter CEO Jack Dorsey is expected to step down from his executive role, sources tell CNBC’s David Faber.

Twitter stock was up on the news before being halted due to news pending.

Dorsey, 45, currently serves as both the CEO of Twitter and Square, his digital payments company.

It’s unclear who’s set to succeed Dorsey or the timing of a potential announcement. It’s also unknown why Dorsey, 45, would take a step back. But if he steps down, the next CEO will have to meet Twitter’s aggressive internal goals. The company said earlier this year it aims to have 315 million monetizable daily active users by the end of 2023 and to at least double its annual revenue in that year.

Dorsey faced an ousting last year when Twitter stakeholder Elliott Management had sought to replace him. Elliott Management founder and billionaire investor Paul Singer had wondered whether Dorsey should run both of the public companies, calling for him to step down as CEO of one of them, before the investment firm reached a deal with the company’s management.

Dorsey, who founded the social media giant, served as CEO until 2008 before being pushed out of the role. He returned to Twitter as boss in 2015 after former CEO Dick Costolo stepped down.

Twitter did not respond to a request for comment.

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