DoubleClick is a subsidiary of Google which develops and provides Internet ad serving services. Its clients include agencies, marketers (Universal McCann Interactive, AKQA etc.) and publishers who serve customers like Microsoft, General Motors, Coca-Cola, Motorola, L’Oréal, Palm, Inc., Apple Inc., Visa USA, Nike, Carlsberg among others. DoubleClick’s headquarters is in New York City, United States.

DoubleClick was founded in 1995 by Kevin O’Connor and Dwight Merriman. It was formerly listed as “DCLK” on the NASDAQ, and was purchased by private equity firms Hellman & Friedman and JMI Equity in July 2005. In March 2008, Google acquired DoubleClick for US$3.1 billion. Unlike many other dot-com companies, it survived the bursting of the dot-com bubble. Today, it focuses on uploading ads and reporting their performance.