Case C-211/18: Judgment of the Court (Sixth Chamber) of 5 March 2020 (request for a preliminary ruling from the Tribunal Arbitral Tributário (Centro de Arbitragem Administrativa — CAAD) — Portugal) — IDEALMED III — Serviços de Saúde, SA v Autoridade Tributária e Aduaneira (Reference for a preliminary ruling — Taxation — Value added tax (VAT) — Directive 2006/112/EC — Article 132(1)(b) — Exemptions — Hospital and medical care — Hospital establishments — Services provided under social conditions comparable to those applicable to bodies governed by public law — Articles 377 and 391 — Derogations — Right to opt for a taxation regime — Maintenance of the taxation — Variation in the conditions for the exercise of the activity)