The company, which went public in March in a $1.8 billion offering, said it lost $2.2 million in the second quarter, which ended June 30, compared to $152,000 in the year-earlier period. Millennial reported a loss of 3 cents per share, beating Wall Street analysts' estimates of 5 cents per share.
Millennial said it has 350 million unique visitors on its ad network, including 140 million in the United States. The company said about 35,000 mobile applications currently run ads from Millennial's network.
The company also boosted its full-year revenue estimates by $3 million, from $176 million to $179 million.