The competent authorities for data intermediation services designated to monitor compliance of data intermediation services providers with the requirements of this Regulation should be chosen on the basis of their capacity and expertise regarding horizontal or sectoral data sharing They should be independent of any data intermediation services provider as well as transparent and impartial in the exercise of their tasks. Member States should notify the Commission of the identity of those competent authorities for data intermediation services. The powers and competences of the competent authorities for data intermediation services should be without prejudice to the powers of the data protection authorities. In particular, for any question requiring an assessment of compliance with Regulation (EU) 2016/679, the competent authority for data intermediation services should seek, where relevant, an opinion or decision of the competent supervisory authority established pursuant to that Regulation.