Undisclosed ads on TikTok skirt ban on profiling minors

The European Union recently introduced strict laws to stop social media platforms from targeting children with personalised advertisements. But a study of TikTok reveals a massive loophole: teens are still being bombarded with highly targeted commercial content disguised as everyday posts.

The EU’s Digital Services Act (DSA) explicitly forbids profiling minors for advertising. However, the legislation defines “advertisements” narrowly, only covering “formal” ads purchased directly through a platform’s own advertising system. It largely ignores influencer marketing and undisclosed promotional videos.

To see how this plays out in practice, Sára Soľárová at the Kempelen Institute of Intelligent Technologies in Slovakia and her colleagues deployed sock puppet automated accounts to TikTok, which simulated 16- to 17-year-old teenagers and 20- to 21-year-old adults. The bots were assigned specific interests, such as beauty, fitness or gaming, and were programmed to scroll through TikTok’s algorithmic For You feed for an hour a day over 10 days.

“The only way for us as a society to understand social media is to study it behaviourally, and this is the way we do it,” says Soľárová.

In total, the bots watched 7095 videos over that period, 19 per cent of which contained some sort of advertisement. Of those advertising videos, around 56 per cent were undisclosed ads, where creators and brands push products without using the platform’s required disclosure labels.

The formal, platform-purchased ads shown to the minor accounts were limited – and in some cases non-existent – and showed no signs of personalised targeting. But the vast majority of the commercial content the simulated teens encountered fell into the undisclosed category.

These hidden ads were aggressively tailored to the teens’ inferred interests. For instance, when a simulated 16-year-old girl showed an interest in beauty, 92.1 per cent of the undisclosed ads algorithmically fed to her explicitly matched that interest.

Overall, the researchers found that this hidden profiling of minors was five to eight times stronger than the level of targeting permitted for formal adult advertising, as measured by the gap between how often an ad matched a user’s interests versus how often it appeared for the average user. That matters because undisclosed ads made up the vast majority minors saw: 84 per cent of ads they encountered were undisclosed, compared with 49 per cent for adults.

“Formally, TikTok complies with the law because it does not profile the formal ads to minors,” says Soľárová. “On that note, TikTok is doing everything it can. But… the disclosed ads represent a small proportion of the total commercial content on the app.” TikTok declined to provide comment for this story.

“These undisclosed ads are a new form of targeted advertising: using consumer preferences to infer the type of content they see, platforms are able to seamlessly deliver more commercial content,” says Catalina Goanta at Utrecht University in the Netherlands.

Goanta believes that responsibility needs to be shared by a broader range of bodies, including regulators. “Influencer marketing has been traditionally understood very narrowly by regulators. Ads that are not disclosed are a harm to consumers,” she says. Soľárová echoes this point: “We have to expand the definition of what advertising is.”