At first glance, it’s just one of Facebook’s many features: depending on the shared information, “People You May Know” suggests profiles to add to your contacts list. However, that “shared information” is only the tip of the iceberg. The truth is that as a social network user, you have a hidden profile, built from data other users have provided about you. The worst part? You can’t see or edit what’s in that profile, and there’s no way to disable it.
There are days when Facebook seems to go through a crisis and starts asking for additional information to complete my profile. City of residence and mobile number are the most frequent requests. I’ve always rejected them for the simple reason that Facebook already has that information. My connection’s IP address gives the social network a solid idea of my location, and as for my phone, well... probably one of my contacts shared that data without realizing it. That brings us to the “People You May Know” section. The first contacts that appear in that list are usually those with mutual friends, but the rest... where do they come from? What kind of processing does Facebook do in the background?
Anecdotes that reveal the mechanism
To better understand “People You May Know,” it’s necessary to review some of its anecdotes on the Web, from dark cases like the classic “Facebook suggested my abusive ex-boyfriend as a friend,” to two patients recommended to each other for the detail of having the same psychiatrist. The social network is known for making mistakes, but what scares here is its mechanism. Suggestions that initially don’t make sense are backed by a chilling amount of data that forms a hidden profile or 'shadow profile.' That data is based on elements like contact information we never provided, and email addresses we never shared... but our contacts did, and that’s the key.
The official explanation
Basically, if a user has your contact information (phone, address, emails) and decides to share it with Facebook, anyone else who has done the same and has similar information will be associated. How exactly does this happen? In reality, one of Facebook’s first recommendations is to 'find friends,' and it invites us to import contacts by entering credentials of other services (Gmail, Yahoo, Outlook). The 'Find Friends' section changes appearance depending on the platform we use, but the function is the same. If we click on the 'how it works' link, Facebook explains that it 'imports contacts from our device and saves them' on its servers to 'help others find people or generate friend suggestions for you and others.' Facebook warns that professional contacts can be imported, however, friend requests should only be sent to personal contacts.
The shadow profile problem
The problem is that we are facing a typical case of 'do as I say, not as I do,' since Facebook will use all that information to expand our hidden profile, that of other contacts, and make suggestions. The social network’s executives reject the term 'shadow profile' for its negative tone, although if it were up to them, we would never know about its existence. Hidden profiles were exposed in 2013, when a user downloaded his internal file, which included the public 'and' hidden data of his friends. Facebook called it a bug, but the genie was out of the bottle and never went back in. Technically, Facebook and WhatsApp users (both services under Facebook’s wing) can also import contacts to the corresponding apps, but spokespeople assure that “People You May Know” only uses data from Facebook and Facebook Messenger.
Everything seems to indicate that the information in hidden profiles has no expiration date. No matter how remote or casual the link, if at some point a person shared their contacts with Facebook and you were among them, now you are part of the package. Multiply that by hundreds of contacts on average, and it’s likely the social network knows everything it needs to know about you, including nicknames, other social profiles, and more. This leads us directly to the trap: you cannot access that information... because it’s not yours in the first place. It was uploaded to Facebook’s servers by other users. That denies us the possibility of managing, editing, or deleting the information 'for privacy reasons.' The interconnection capacity is so powerful that the famous six degrees of separationare just three and a half inside the social network.
No way out
Hidden profiles cannot be deactivated, and there is no opt-out. The only thing Facebook allows is to block the search of our profile via email addresses or phone number in the Privacy section. And filling public profiles with false information has limited effect, because Facebook only needs one user willing to share their contact information, and we are in their address book.
