This deliverable consists of an introduction and two main parts. Each part consists of two sections:Data exchange and interoperability and Demand-side flexibility. The two main topics of this interim deliverable, data exchange and interoperability and Demand-Side Flexibility (DSF), were identified as relevant research domains in the regulatory gap analysis performed in INTERRFACE Deliverable D2.4 Completed Regulatory Framework (Schittekatte et al. 2019).1 These two topics have been listed as European priority legislations. The relevance of the network code on Demand-Side Flexibility (DSF) has been confirmed in the priority list for new network codes for 2020-2023 published on 14 October 2020 by the European Commission. The implementing act on interoperability is described as a priority action in the European Energy System Integration Strategy published in July 2020 by the European Commission. Please note that our work around flexibility market design as part of D2.4 is also very relevant with regards to the planned new network code on DSF. We chose not to include that research in this deliverable as it is already published as part of D2.4 but we plan to integrate it, possibly including some updates, in the final deliverable of T9.4. The research results have a two-fold purpose. First, the research results feed into the ongoing discussions at national and European level around the new European legislations. Second, the research results are of direct use for the project partners who are involved in the INTERRFACE demonstrators.