Judgment of the Court (Fourth Chamber) of 5 June 2019.#Skype Communications Sàrl v Institut belge des services postaux et des télécommunications (IBPT).#Request for a preliminary ruling from the Cour d'appel de Bruxelles.#Reference for a preliminary ruling — Electronic communications networks and services — Directive 2002/21/EC — Article 2(c) — Notion of ‘electronic communications service’ — Transmission of signals — Voice over Internet Protocol (VoIP) service to fixed or mobile telephone numbers