CELEX:62021CA0127: Case C-127/21 P: Judgment of the Court (Third Chamber) of 16 March 2023 — American Airlines Inc. v European Commission, Delta Air Lines Inc. (Appeal — Regulation (EC) No 139/2004 — Concentrations between undertakings — Air transport market — Concentration declared compatible with the internal market — Commitments entered into by the parties to the concentration — Decision granting grandfathering rights — Concept of ‘appropriate use’)