Empirical insights on sources of knowledge in the Digital Markets Act ’s enforcement

Within three years of the Digital Markets Act (DMA) becoming applicable, the European Commission (Commission) has not only issued numerous designation decisions, but also two crucial non-compliance decisions, as well as adopted a number of other measures based on this regulation. This article analyses the references identified in the decisions adopted until July 2026, with a view to providing insight into what sources of knowledge the Commission uses when enforcing the DMA and what the functions of these references are. The results show that the catalogue of types of sources of knowledge invoked in the decisions is quite broad and includes, for example, reports and cases from other jurisdictions. However, the most frequently invoked source of knowledge is that from the industry. The analysis reveals that, although sources are diversified with regard to the conceptualization of market characteristics, knowledge from market participants is crucial for analysing a given infringement.