Only the tenants named in the contract are allowed to live in the apartment. If the landlord discovers that other people are living there, they may increase the rent or terminate the agreement.
You may not sublet the apartment, or any part of it, to another person without the landlord’s prior written consent.
You must also inform the landlord about any person who is not listed in the agreement and stays in the apartment for more than 24 hours or uses it for overnight stays.