Key legal question
Whether the tenants' rent deposit was valid despite lack of the formal notice and deadline under Art. 259g CO, invoking Art. 108 ch. 1 CO.
Extracted holding
The deposit was not valid because the tenants had not first demanded repair in writing and threatened deposit; Art. 108 ch. 1 CO did not excuse these formalities on the facts.
Extracted reasoning
The landlord had not clearly shown an absolute refusal to remedy the defects. The tenants therefore had to comply with the statutory formal steps; good faith cannot generally replace mandatory formal requirements.