Twitter announced late on Thursday that CEO Dick Costolo has quit, and will be replaced by co-founder Jack Dorsey on an interim basis from 1 July.
"There is no one better than Jack Dorsey to lead Twitter during this transition. He has a profound understanding of the product and Twitter’s mission in the world as well as a great relationship with Twitter’s leadership team," said Costolo, adding that he was "tremendously proud" of the company’s achievements during his six years in charge.
Costolo has been under pressure to spur stronger growth in Twitter’s user base, which has been slowing in recent quarters, and to generate more money from the service.
The company added 47 million monthly active users in the 12 months to 31 March, leaving it with 302 million monthly active users.
In the first three months of 2015, Twitter generated revenue of US$436 million, missing the low end of its forecast range of $440 million-$450 million. It also lowered its full-year revenue outlook due to a lower-than-expected contribution from its direct response advertising products.
Twitter’s board has formed a search committee to find a permanent replacement.
Twitter’s shares jumped 7% when Costolo’s resignation was announced.
"Dick has put a world-class team in place and created a great foundation from which Twitter can continue to change the world and grow," said Dorsey, who added that he looks forward to "continuing to execute our strategy while helping to facilitate a smooth transition as the board conducts its search."
