DeneyTerrio, Jurvetson, BloomEnergy / flickr
The move would be a logical step given that Google just became an ad-buyer inside Facebook, too.
For consumers, the move would create a formidable online ad environment: Previously, all three companies targeted consumers with ads separately. With the Amazon move, any consumer could be cross-targeted across all three companies, as the three companies would have to cooperate in serving data to each other in one way or another.
AdExchanger had only the barest of details on Amazon's entry into Facebook's FBX:
Amazon, the ever-silent commerce stalwart, may be next in line to join the Facebook Exchange party, according to AdExchanger sources.
Facebook, Google and Amazon all have their own ad exchanges. They work by allowing buyers to target the tracking cookies that users create as they surf around the web. Once you enter Facebook, Google or Amazon carrying one of those cookies, the three companies let other advertisers target you with ads that might be relevant to you, based on your browser history.
But only recently have the three companies begun cooperating within each other's targeting environments. For a long time, Facebook kept Google out of FBX, for fear that Google might get a look at its performance data. That changed last week. Google brings a big new set of clients inside Facebook - likely pushing up prices due to higher demand. (Facebook has traded a loss of data for more potential money, in other words.)
By allowing Amazon into FBX, Facebook could make the same tradeoff: It would get more money from ad buyers using Amazon's "demand-side platform" (a DSP is the buying platform Amazon's clients use to buy ads in exchanges across the web).
Amazon has previously had a two-pronged strategy as an ad buying platform: Its clients have been able to use Triggit, an independent company that Amazon has used as a DSP, or Amazon's own purpose built DSP.
To speculate further, there is one obvious piece missing from this puzzle: A Facebook DSP, allowing Facebook's clients to target Facebook users in ad exchanges outside Facebook.
Stay tuned.
Disclosure: Jeff Bezos is an investor in Business Insider through his personal investment company Bezos Expeditions.