Speed Reads

Revolving Door

Twitter CEO Dick Costolo to step down

Twitter CEO Dick Costolo is set to step down in July, according to a document released to shareholders on Thursday. Jack Dorsey, the social media giant's co-founder, will step in as the company's interim CEO.

Though he'll no longer be at Twitter's helm, Costolo will remain on the company's Board of Directors. Dorsey, who co-founded the mobile payment company Square Inc. in 2009, will also continue to hold his post as Square's CEO, according to a statement released by Twitter.

Costolo became CEO in October 2010, replacing co-founder Evan Williams. Since Twitter went public in 2013, Costolo has become a controversial figure, said to be respected by Twitter's employees but a disappointment to the company's Wall Street investors.