Doubleclick would not comment on the reports.
DoubleClick is majority owned by Hellman & Friedman, a private equity firm. A source quoted in The Wall Street Journal said the firm is seeking $2 billion for DoubleClick.
Pieces of DoubleClick have been sold off over the past two years as the company concentrated on online services. Most recently, it sold its profitable Abacus unit, which handles data management and analytics, to Alliance Data Systems Corp.’s Epsilon.