On 15 January 2026, the Belgian High Court delivered a judgment in proceedings initiated by the Belgian Supervisory Authority, in which it challenged the scope of judicial review exercised by the Market Court over its enforcement decisions. The authority was unsuccessful on both grounds of appeal.

By way of background, the Supervisory Authority had adopted an enforcement decision imposing an administrative fine on the Belgian railways. The company appealed that decision before the Market Court, which reduced the fine to a symbolic amount of 1 EUR.

First, the High Court rejected the Supervisory Authority’s argument that the Market Court may only annul a fine and remit the case to the authority for reconsideration. The High Court instead held that the Market Court has full jurisdiction to review Authority’s decisions and may revise the fines, including by reducing the amount where it finds it to be disproportionate.

Second, the Supervisory Authority contended that the imposition of a symbolic 1 EUR fine was incompatible with the GDPR, on the ground that such a fine could not be regarded as effective, proportionate, and dissuasive within the meaning of Article 83(1) GDPR. The High Court again disagreed, holding that, in appropriate circumstances, a fine of 1 EUR may satisfy those requirements.

The High Court found that there was no need to refer a preliminary question to the Court of Justice of the European Union.

From a practical perspective, this judgment is significant for GDPR enforcement in Belgium because it confirms that appeals before the Market Court can involve a genuine assessment of the proportionality of administrative fines. The Supervisory Authority will have to anticipate that its sanctions may be fully reviewed and, where appropriate, adjusted.