Judgment of the Court (Second Chamber) of 14 December 2023.#European Commission v Grand Duchy of Luxembourg and Others.#Appeal – State aid – Article 107(1) TFEU – Tax ruling adopted by a Member State – Aid declared incompatible with the internal market – Concept of ‘advantage’ – Determination of the reference framework – ‘Normal’ taxation according to national law – Arm’s length principle – Review by the Court of Justice of the interpretation and application of national law by the General Court.#Case C-457/21 P.