ABSTRACT The paper explores the balance between interoperability and innovation within the context of the Digital Markets Act (DMA) and competition law. It discerns vertical interoperability obligations (Article 6(4) and 6(7)) from the horizontal interoperability obligation (Article 7) and highlights the following. First, the EU competition law is more experienced in dealing with vertical interoperability which favours innovation incentives for SMEs and new entrants over those for established incumbents (the incentive-balance test). This approach may encourage sustaining innovation at the downstream level by fostering competition and could eventually lead to disruptive innovations as new entrants gain experience and resources. Secondly, EU competition law is not well-versed in horizontal interoperability obligations. While Article 7 may boost innovation through increased competition, considerations related to privacy and standardization make its (potentially benign and adverse) effects on innovation uncertain.