Case C-683/19: Judgment of the Court (Fifth Chamber) of 14 October 2021 (request for a preliminary ruling from the Tribunal Supremo — Spain) — Viesgo Infraestructuras Energéticas SL v Administración General del Estado and Others (Reference for a preliminary ruling — Common rules for the internal market in electricity — Directive 2009/72/EC — Article 3(2) and (6) — Imposition of public service obligations — Financing of a regulated discount for the purpose of the protection of vulnerable consumers — Requirements of transparency and non-discrimination)