Meta Platforms and TikTok secured a legal victory Wednesday against the European Union over how regulators calculated supervisory fees under the bloc's flagship Digital Services Act, in a ruling that forces Brussels to overhaul its methodology but stops short of refunding payments already made.

The Luxembourg-based General Court, part of the Court of Justice of the European Union, ruled that the European Commission used the wrong legal instrument to establish its fee system, which imposes a levy of 0.05% of global net income on very large online platforms to fund enforcement of the DSA. Judges said the methodology should have been adopted through a delegated act, not by implementing decisions. The Commission now has 12 months to correct the procedure.

Meta and TikTok had challenged the Commission's calculation, arguing the formula unfairly shifted costs to profitable companies while loss-making platforms with large user bases escaped payment. The court sided with the companies, though it did not order reimbursement of the 2023 fees.

"The Court confirms our methodology is sound: no error in calculation, no suspension of any payments, no problem with the principle of the fee nor the amount," Commission spokesperson Thomas Regnier said, framing the ruling as a procedural setback rather than a substantive defeat.

TikTok welcomed the decision, saying it would "closely follow the development of the delegated act." Meta said the judgment "will force the European Commission to reassess the unfair methodology being used to calculate these DSA fees" and called for changes that ensure costs are shared more proportionately.

The case marks the first significant loss for Brussels in defending the DSA, which came into force in late 2022. The law requires platforms with more than 45 million monthly active users in the EU to take stronger action against harmful and illegal content or face fines of up to 6% of global annual revenue.

Other companies subject to the supervisory fee include Amazon, Apple, Google, Microsoft, Booking.com, Snap, Pinterest and Elon Musk's X. Regulators say the levy reflects a "polluter pays" principle, ensuring the largest platforms bear the costs of oversight.