How Facebook Tracks Your Offline Purchases Too

It’s a well-known fact that Facebook tracks your every move online for the purpose of serving targeted ads. Along with that, Facebook also tracks the performance of its ads by tracking your buys online and matching them with the ads that were displayed to you. What isn’t known, however, is that Facebook can now tell if an online ad influenced your purchase in-store (offline).

Surely you’ve experienced this scenario many a time before: while completing your purchase, the cashier prompts you to enter your phone number and/or email address for the purpose of sending you promotional emails or coupons. Now, that phone number or email address can be used for other purposes as well. Internet giants like Facebook can use that same email to match the purchase to your profile. This way, they can tell if an ad that was shown to you actually influenced your decision to buy, even if you didn’t buy online.

This new system by Facebook is called Atlas (although it has been getting done by Facebook for over 2 years now, it wasn’t public). The system is anonymous, so you don’t have to worry that your identity will be exposed. Facebook collaborates on this project with DataLogix – a data collection company that has access your phone number and email from retailers. The two companies both create an anonymizing hash of your phone number/email which they can then compare. Since they use the same algorithm to anonymize your phone number/email, both of their hashes will be identical. Your offline shopping history cannot be matched to your real identity, however, because not even Facebook knows what hash belongs to whom, or so they say.

This, however raises concerns in some people who do not wish to be tracked even if it’s anonymous. How do you feel about Facebook’s tracking system? Share your opinion about it by taking the survey below.