European Commission finds TikTok breached advertising transparency rules

The European Commission has delivered a preliminary verdict that TikTok is in breach of the Digital Services Act's advertising transparency obligations, opening the door to a fine of up to 6% of the platform's global annual turnover. The finding, published on Thursday, concludes an investigation launched in February 2024 into whether the Chinese-owned short video service provides the searchable advertisement repository the law requires.

What the Digital Services Act demands

Under the DSA, very large online platforms must publish an advertisement library that details the content of each ad, the parameters used to target users, and the identity of the person or entity that paid for it. The repository must be publicly searchable. Commission officials regard this as a vital tool for researchers, journalists and civil society to detect scam advertisements and coordinated campaigns that seek to manipulate public opinion, particularly during election periods.

The Commission said TikTok did not provide this information and did not allow the public to search for it. That failure, in the Commission's view, constitutes a breach of Article 39 of the DSA. If the preliminary finding is upheld after TikTok exercises its right of defence, the company would be ordered to bring its ad repository into compliance and could face the maximum financial penalty the regulation allows.

The Romanian election context

The advertising transparency verdict arrives four days before what Romanian officials have called "super Sunday", the second round of a rescheduled presidential election. The first round, held in November 2024, was annulled by Romania's Constitutional Court after intelligence services alleged that Russia had mounted an online campaign to promote a far-right outsider, Călin Georgescu, who topped the poll. That episode triggered a separate Commission investigation, launched in December 2024, into whether TikTok failed to mitigate systemic risks to election integrity on its platform.

Ursula von der Leyen, the Commission president, said at the time that there were "serious indications that foreign actors interfered in the Romanian presidential elections by using TikTok." The ongoing probe examines whether the platform's design, algorithms and content moderation allowed such interference to spread unchecked. Sunday's run-off pits Georgescu against Elena Lasconi, the reformist mayor of Sibiu.

Commission separates the two cases

Thomas Regnier, a Commission spokesperson, was careful to distinguish the advertising transparency finding from the election integrity investigation. "Of course it's not helping that your ad repository is not working. That's one fact because it doesn't help us to assess if there were fake or scam ads being used in the context of elections," he said. But he added: "The fact that the ad repository is not working in the context of this February investigation of last year is absolutely not prejudging the outcome of the December investigation."

The distinction matters. The advertising repository case is a procedural breach: the platform did not build the tool the law requires. The election integrity case is a substantive one: whether TikTok's systems amplified or failed to remove coordinated inauthentic behaviour that may have influenced a presidential election. The Commission is studying actions TikTok says it took to prevent interference in Romania, but has not yet reached a preliminary view.

TikTok's response

A TikTok spokesperson said the company was reviewing the Commission's preliminary findings. "While we support the goals of the regulation [DSA] and continue to improve our ad transparency tools, we disagree with some of the Commission's interpretations and note that guidance is being delivered via preliminary findings rather than clear, public guidelines," the company said. The statement points to a broader tension: platforms argue the DSA's obligations are sometimes vague, while regulators counter that the law sets outcomes, not technical specifications, and that companies with TikTok's resources should be able to comply.

TikTok now has access to the Commission's investigation file and can submit a formal defence. The Commission will then decide whether to confirm its preliminary view and issue a final decision. There is no fixed statutory deadline for that final decision, though the DSA requires the process to be conducted within a reasonable time.

Other open investigations

The advertising repository probe was one of several opened simultaneously in February 2024. The Commission is also investigating whether TikTok's recommendation algorithms lead users down damaging content "rabbit holes" and have addictive effects, particularly on younger users. A third strand examines the platform's age verification and child safety policies. Both remain incomplete. The Commission said it continues to investigate "other suspected offences under EU law" without specifying a timetable for conclusions.

These parallel inquiries reflect the DSA's systemic risk framework. The regulation requires very large platforms to assess and mitigate risks ranging from the dissemination of illegal content to negative effects on mental health, civic discourse and the rights of the child. The Commission's enforcement strategy has been to open multiple proceedings early, then resolve them sequentially as evidence is gathered.

Why the ad repository matters for elections

Researchers who study online political advertising have long argued that a functional, searchable ad library is the single most effective transparency measure. Without it, they cannot map who is paying to reach which voters, identify coordinated networks buying ads across multiple pages, or detect foreign state actors masking their involvement. The Romanian case illustrates the stakes: if a foreign power buys political ads on TikTok targeting Romanian users, the absence of a public repository means the interference may only be discovered after the vote, if at all.

The Commission's own assessment capabilities are similarly hampered. Regnier's comment that the broken repository "doesn't help us to assess if there were fake or scam ads being used in the context of elections" is an admission that the regulator itself relies on the very transparency tools the DSA mandates. When platforms fail to build them, oversight becomes reactive rather than preventive.