Dick Costolo became Twitter’s chief executive officer in October 2010, succeeding co-founder Evan Williams. Costolo had joined Twitter as chief operating officer in 2009 and helped build its commercial operations.
During Costolo’s tenure, Twitter became a publicly traded company in 2013 and expanded its advertising products, including promoted tweets and promoted accounts. The company also acquired Vine and continued developing its global user base. Costolo remained CEO until July 2015.
The succession is often confused because Jack Dorsey returned as CEO after Costolo stepped down. Dorsey served as interim chief executive before becoming permanent CEO again. Parag Agrawal followed Dorsey in November 2021, so he was not Costolo’s immediate successor.