Kuka vartioi portinvartijaa? Who guards the gatekeeper?

The Digital Market Act (DMA) introduces rules for platforms that act as gatekeepers in the digital sector. The DMA aims to address concerns regarding contestability and fairness in the digital economy. This article compares DMA with Article 102 TFEU that prohibits abuse of dominant position. While competition law enforcement is based on an (ex post) evaluation of the conduct of the dominant company, the DMA introduces (ex ante) regulation with a number of strict prohibitions and obligations on digital gatekeepers that offer core platform services. We will first examine the central content of the DMA through the lens of competition law. After this, the relationship between the digital market regulation and the prohibition of abuse of a dominant position will be considered. The DMA is compared to Article 102 from the point of view of the material content and regulatory approach, what are the similarities and what are the differences. The purpose is also to understand how the regulatory environment changes with the DMA. Finally, the article considers more generally the relationship between competition law and regulation in the digital markets and the grounds for introducing the new regulation.