Anyone who has used TikTok for any length of time can attest to the app's compelling properties. The algorithm that determines what short-form video content is shown on your personal For You Page is famous for driving people into endless-scrolling cycles that are hard to break out of.

It's that way by design. But that's the problem: The European Commission has published preliminary findings declaring that TikTok's "addictive by design" strategy, which it's been investigating since 2024, violates the Digital Services Act. That landmark EU regulation from 2022 seeks to impose accountability on large online platforms, including their content moderation practices

TikTok will need to make major changes to how its algorithm works or face fines of up to 6% of its annual global turnover, the Commission said. It highlighted specific features it found problematic, including infinite scroll, autoplay, push notifications and TikTok's highly personalized recommendation system.

The Commission is particularly highlighting how the addictive features of the app could harm the physical and mental well-being of users, including minors and vulnerable adults. Its decision comes in the same month Spain announced it would implement a social media ban for minors under 16, similar to the one already in place in Australia. Other European countries, including France and the UK, could be moving toward similar rules.

"The Digital Services Act makes platforms responsible for the effects they can have on their users," said Henna Virkkunen, the Commission's executive vice president of tech sovereignty, in a statement. "In Europe, we enforce our legislation to protect our children and our citizens online."

It's already been a rocky year for TikTok, as the US version of the app has been split off from the global business to meet the requirements of a US law from 2024. Further algorithmic changes are coming, with TikTok fans already noting major shifts on the platform in the US, sparking an immediate exodus from the app. 

As for Europe, TikTok doesn't seem to be taking the Commission's accusations and demands lying down.

"The Commission's preliminary findings present a categorically false and entirely meritless depiction of our platform, and we will take whatever steps are necessary to challenge these findings through every means available to us," a spokesperson for the company said via email.

TikTok will be able to examine the documents in the Commission's investigation files and file a response.

An end to "dark design"?

A combination of internal data collected from TikTok and top scientific research on the harmful effects of social media led the Commission to conclude that the company is not acting in people's best interests by allowing them to slip into compulsive behaviors.

TikTok is far from the only platform that relies on algorithms designed to keep people hooked to the app without a break. The reason it's been singled out here, said social media expert Matt Navarra, is "because it's the algorithmic and design blueprint for these types of social apps that everyone else has copied." Plus, he added, it's also got the most cultural impact and works, if anything, too well.

"You open the app, you're in the loop, and then within half a second, no decisions, no dead ends, just pure dopamine, and that's the real reason TikTok is in the firing line," said Navarra.

The European Commission's message here is that this kind of design is not "clever," but, in fact, "illegal." It's framing this fight with TikTok as a public health issue, using the Digital Services Act as a legal framework to hold the company accountable for the consequences of its decisions.

Does Navarra think TikTok's closest rivals -- Instagram, YouTube, Snap -- should be worried that they might be next? Yes, he said. 

"The bottom line is that this is probably the start of a global reckoning about dark design choices on social media apps, and TikTok just became the test case."