This paper analyses certain aspects of the Commission’s proposal for the Digital Markets Act (DMA) of December 15, 2020 and the changes proposed by the Schwab Report for the European Parliament on May 31, 2021. It identifies shortcomings of the proposed DMA and makes suggestions for improvements by comparing the DMA to telecommunications regulation, the EUMR and the new § 19a Act against Restrictions of Competition (ARC). It will, first, take a look at the problems addressed by the DMA (II) and the question of whether the DMA’s objectives are defined in a sufficiently clear manner (III). The analysis then turns to legal certainty and due process with regard to the gatekeeper designation according to Art. 3 DMA (IV). The paper takes a critical look at the self-executing nature of the obligations in Art. 5 and 6 DMA. It raises questions with regard to the balance between ease and speed of enforcement, on the one hand, and the principles of proportionality and due process, on the other (V). Finally, the paper turns to the aspects of effective judicial protection and private enforcement (VI).