This study examines whether horizontal interoperability obligations similar to those already in place for number-independent interpersonal communications services (NIICS) under the Digital Markets Act (DMA) could be extended to online social networks (OSNs) and, if so, under what conditions. The demand for a potential extension of vertical interoperability requirements to OSNs in the context of the DMA is also considered. The study draws on insights from an academic focus group, stakeholder interviews and a representative consumer survey alongside the review of technical and academic literature in the field of interoperability. The study also takes into account feedback from relevant stakeholders gathered from a workshop that took place in Brussels, where preliminary conclusions of this study were presented by the research team.
The study concludes that, although some aspects can be challenging to implement, horizontal and vertical interoperability for OSNs is technically feasible. However, the approach to interoperability designed for NIICS cannot simply be transposed to OSNs, as the OSN landscape is more diverse in terms of functions, architectures, and business models. Any extension of interoperability obligations under the DMA to OSNs, in particular of horizontal nature, would need to be tailored in a way that takes into account user demand, technical and organisational feasibility, the impact on innovation and market contestability, and the risk of unintended consequences such as the potential further entrenchment of gatekeepers. This study therefore recommends to continue monitoring the implementation of existing interoperability obligations for NIICS as well as the evolution of usage of OSNs.
