Jack Dorsey would have to give up his post at Square if he wants to become permanent CEO of Twitter. The company he helped found and now leads on an interim basis said Monday that it is only considering candidates who can make a 'full-time commitment to Twitter.' Dorsey was named interim CEO after Dick Costolo stepped down effective July 1 amid criticism over Twitter's disappointing financial performance and share price decline. Costolo had been Twitter's CEO for five years and led the company through a successful stock market debut in 2013. But Twitter has yet to make a profit and there are concerns about its ability to grow its user base.Costolo stepping down from his role beginning July 1Costolo faced controversies over online abuse and user numbersBoard only considering candidates who can make 'full-time commitment' 
 Question:_ has been under the microscope since going public in late 2013, and has struggled to deal with user growth issues that have seemed to show the company had hit a plateau.
Twitter