The Requisite Legal Standard of the Digital Markets Act's Designation Process.

This article critically examines the European Commission’s initial enforcement of the Digital Markets Act (DMA), focusing on the legal standards applied in the September 2023 designation decisions that identify gatekeepers and their core platform services (CPSs). It highlights the Commission’s discretionary approach in delineating CPSs—distinguishing between different services and their purposes—which departs from the DMA’s text and borrows concepts from EU competition law, resulting in inconsistent application across gatekeepers and service categories. The paper also analyzes the rebuttal process allowing designated gatekeepers to contest their status, noting that while qualitative and quantitative arguments are theoretically admissible, the Commission applies a high evidentiary threshold and unevenly accepts such arguments. Overall, the study reveals tensions between the DMA’s intended bright-line rules and the Commission’s flexible, case-by-case enforcement, raising questions about legal predictability and the scope of the Commission’s discretion in regulating digital markets.