Facebook recently certified Google’s DoubleClick as an approved third-party ad tracker, giving advertisers more flexibility in how they measure impressions, clicks and interactions with their Facebook campaigns.

The social network does not allow third-parties to collect impression tracking data through tracking pixels or tags unless they are certified with Facebook. However, recently Facebook has been expanding its list of partners as brand and agency advertisers look for more ways to understand how their social ads are truly performing.

AdExchanger first reported the DoubleClick approval on Wednesday, citing unnamed sources. AdExchanger also says Adometry was approved in July. The Facebook Help Center confirms the addition of DoubleClick, though it does not mention Adometry. Microsoft’s Atlas was approved in late June.

Clients of these services can submit tracking tags along with their creative to Facebook during trafficking. This will allow advertisers to track through to conversion on off-Facebook websites, and view Facebook campaigns alongside their other media efforts.

The social network recently expanded its own conversion tracking capabilities that seem to work with Facebook user IDs rather than cookies. Advertisers using the Ads API can now get reports of post-click and post-impression actions, including what users do on a company’s Facebook page or actions they take in Open Graph apps. That means in addition to being able to track whether people who saw an ad checked into a location or claimed an offer, advertisers can also create custom Open Graph actions for anything they want to track on a third-party site or mobile app. For example, a retailer could run ads promoting a loyalty program that ties a user’s rewards card with their Facebook profile. With the new conversion tracking, the retailer would be able to see which ads drove in-store purchases.

Other third-parties allowed to use cookie tracking include Bloom Digital, Flashtalking, GroupM, Mediamind, Mediaplex, Pointroll, TruEffect and Weborama.

Facebook is also testing a new real-time bidding exchange that will allow third-party platforms to place retargeting ads on Facebook after users visit external websites marked with cookies. DoubleClick’s demand side platform, DoubleClick Bid Manager, is not included in that test.