Kernrechtsfrage
Whether the employer was subject to the collective labor agreement and who bore the burden of proof
Extrahierter Entscheid
The employee bore the burden of proving that the CCT applied, including the positive and negative scope conditions; the employer did not have to prove an exception.
Extrahierte Begründung
Article 3.2.1 CCT sets one set of applicability conditions rather than a general rule plus an exception. Under Art. 8 CC, the party asserting the CCT's applicability must prove it. The lower court correctly found that it was not established that the employer maintained products other than its own.