Atlas, an advertising suite, was acquired by Facebook from Microsoft. Facebook said it the reason the it purchased the ad network was to help advertisers "close the loop" and understand how their spend earns them money.
The Atlas team that was based in Seattle stays, and Facebook invests in back-end scaling for better measurement.
Before being acquired by Facebook, Microsoft had been aggressively searching for a buyer and that the price had to be less than $100 million, following previous bids in the $30 million to $50 million range. Microsoft originally acquired Atlas through a $6 billion purchase of aQuantive.
Atlas allows advertisers to plan campaigns, buy ads on sites across the web, and measure their impact. It can handle search, rich media and in-stream video, and display ads, as well as offer APIs for programmatic control of big campaigns.