• by Steve Smith  @popeyesm, January 5, 2012

Millennial Media has filed its S-1 with the SEC to initiate a proposed Initial Public Offering with a maximum offering price of $75 million. The long-expected IPO is from what analysts estimate is the second-largest mobile ad network in the U.S. after Google.  

In its S-1 filing, the company revealed that it had $69 million in revenue for the first three quarters of 2011 and posted a net loss of $417,000. The company claims that it grew revenue from $16.2 million in 2009 to $47.8 million in 2010, with a net loss dropping to $7.1 million from $7.6 million. In 2011, Millennial says its gross margins improved from 33% to 39% as its revenues were up 138% in the first nine months. About 10% of revenue is from outside the U.S.

Millennial says that in December 2011 it served 40 billion ad impressions. Over 28,000 apps carry Millennial ads, and the company claims a reach of over 200 million unique users.

The IPO was expected. While early mobile ad networks AdMob, EnPocket and Quattro got eaten by Google, Nokia and Apple, respectively, Millennial remained independent and grew to achieve more ad revenue than Apple and its iAds network, according to analysts.  

The bankers involved in the IPO are Morgan Stanley, Goldman Sachs and Barclays.