Judgment of the Court (Fourth Chamber) of 9 September 2021.#Adler Real Estate AG and Others v Finanzmarktaufsichtsbehörde (FMA).#Request for a preliminary ruling from the Bundesverwaltungsgericht.#Reference for a preliminary ruling – Securities admitted to trading on a regulated market situated or operating within a Member State – Obligation of transparency – Notification of ‘major holdings’ in companies acquired by ‘persons acting in concert’ – Directive 2004/109/EC – Fourth subparagraph of Article 3(1a) – Concept of ‘more stringent’ requirements – Directive 2004/25/EC – ‘Supervision’ by an authority designated pursuant to Article 4 of that directive.#Case C-605/18.