She takes on the newly created chief marketing officer role at the business and will be responsible for worldwide advertising and branding efforts.
Additionally, Spilman will serve as the company’s executive vice president as it looks to step up its efforts to compete with rival mobile advertising networks Google Admob and Apple’s iAd.
The company says Spilman will be tasked with capitalising on the growing opportunities around “mobile monetisation and the app economy”.
Paul Palmieri, president and chief executive at Millennial Media, adds: “Mollie has a proven track record of developing and executing successful marketing strategies that deliver results. A rapid consumer shift to mobile has brought about a once-in-a-generation opportunity, and Mollie’s vision and strategic approach will play an essential role in defining the future of mobile advertising and allowing Millennial Media to grow our leadership position in the space.”
Spilman left Yahoo! in August after just three months as its chief marketing officer following an overhaul of the company’s senior management team by chief executive Marissa Mayer. Spilman was replaced by the founder of social commerce startup Kathy Savitt.
At Yahoo!, Spilman also ran its Americas marketing for two years. She has also held senior positions at Discovery Communications, Meredith Corp and Time Warner.