Despite being competitors, Google and Facebook have announced a partnership in which the search giant’s DoubleClick Bid Manager will become part of the FBX network. This means that Google’s ad partners will be able to deliver retargeted ads on Facebook based on web browsing history.

Launched in June 2012, FBX lets advertisers buy cookie-based retargeted ads on the social network. Essentially, if someone didn’t purchase a flight while visiting a travel site, the site can show them ads promoting the same flight at a discount in hopes of getting that person to complete the transaction.

DoubleClick allows clients to buy ads on several different ad exchanged, but until now it has excluded Facebook forcing some to look elsewhere for their media buying needs. Upon integration, DoubleClick will be more of a one-stop-shop for purchasing ads across the web.

Here’s how it works: When someone visits an advertisers website, a cookie is added to that person’s computer. The site can then pass this cookie on to a demand side platform (DSP) that uses it to target that same person with an ad on Facebook. Soon, DoubleClick will become one of these DSPs.

Although current DSPs like AdRoll and DataXu will now have to compete with Google, this partnership is great news for Facebook Exchange and retargeting as an ad format. In theory, this could improve the quality of Facebook Ads and bring in more revenue, which will hopefully motivate the social network to bring retargeting to mobile.

Advertisers looking to take advantage of the partnership won’t be able to right away; according to Google, the integration won’t be complete for a “few months.”

[Via: TechCrunch, Image credit: Keno]