Judgment of the Court (Third Chamber) of 9 November 2023.#Altice Group Lux Sàrl v European Commission.#Appeal – Competition – Control of concentrations between undertakings – Regulation (EC) No 139/2004 – Plea of illegality – Article 4(1) – Prior notification obligation for concentrations – Article 7(1) – Concentration standstill obligation – Scope – Concept of the ‘implementation’ of a concentration – Article 14(2) – Decision imposing fines for implementing a concentration before its notification and clearance – Obligation to state reasons – Principle of proportionality – Unlimited jurisdiction.#Case C-746/21 P.