Facebook Ads Can Be Used to Target Individual Users

Published · Oct 20, 2021

Academics have released a study detailing the ability to "nanotarget" through Facebooks Ads. The concern is that individuals' interests can single them out, and make them vulnerable to manipulation and identification.

The researchers managed to use Facebook’s advertising tools to send adverts to selected users. For the purposes of the study, the academics involved were selected as targets. In one round of testing, 8/9 adverts successfully reached the intended individual, and only them.

Facebook assigns users “interests” based on their activity. They’re mostly accurate, although they can sometimes be random. Targeted advertising works by matching ad campaigns to users based on their assigned interests and displaying the corresponding ads.

The study ran multiple campaigns using sets of between five to 22 interests. The researchers found that knowing 18+ of someone’s assigned interests is enough to nano target them with high accuracy.

Identification and Manipulation

Facebook has nearly three billion users. The fact that someone can target a single person amongst such a great number is alarming. It means that individuals can potentially be identified by their activity and subjected to manipulative adverts.

Although the researchers don’t refer to interests as “personally identifiable information” (PII), the GDPR’s definition of PII is broader. It refers to information like name, address, etc., but also things that can indirectly lead to identifying a person, like their interests.

By assigning interests to users, Facebook is effectively creating individual profiles. The bigger they get, the easier it will be to pinpoint people based on that information.

There is also contention around the legality of all this. Publicly listed data is fair game for collection and is often scraped by background checks and people search sites. Companies don't use this data “on” individuals either.

Targeted advertising is different. Facebook uses niche information about individuals to advertise to them. If executed correctly, it could allow parties to unduly influence users.

The GDPR legislation is leaning toward the opinion that this practice is unlawful. Facebook maintains that people agreed to it when signing up and continue to consent by using the service.

Regulators are scrutinizing not only Facebook but tech firms across the board. This study on just how laser-focused targeted advertising can be is sure to inform the regulator’s efforts going forward.

In the meantime, users worried about targeted advertising can use solutions like VPNs to anonymize themselves. However, there’s not much else they can do to protect their privacy online.

Garan van Rensburg
Garan van Rensburg

Garan is a writer interested in how tech reshapes the environment, and how the environment reshapes tech. You'll usually find him inoculating against future shock and arguing with bots.