Revocability of a collective agreement amendment and the scope of individual wage claims under collective bargaining law

The Federal Labour Court (BAG) reversed the Landesarbeitsgericht decision, reinstated the Arbeitsgericht judgment, and dismissed the plaintiff's appeal, ordering the plaintiff to bear the costs of the appellate and revision proceedings. The dispute concerned a civil labour law claim, where the plaintiff sought redress against the defendant, and the revision was filed by the defendant to overturn the lower appellate court's ruling. The decisive legal basis involved the application of substantive labour law doctrines and procedural requirements governing revision appeals, where the BAG found in favor of the defendant, thereby restoring the initial lower court's dismissal of the plaintiff's claims.