Facts
In this case, it was about a rent increase where the form for notifying the increase only showed facsimile instead of handwritten signatures. The tenant (appellant) then asserted the formal invalidity of the rent increase and demanded the refund of the paid rent differences.
The lower court recognized that the formal requirements under Art. 269d CO had not been complied with. However, the rent increase was to be considered formally valid due to the handwritten signed cover letter. Furthermore, the tenant's assertion of the formal defect was considered an abuse of rights, as the tenant had paid the increased rent without reservation for 6 years without challenging the rent increase.
Considerations
The Federal Supreme Court confirmed the view of the lower court. It stated that the purpose of the form requirement is primarily to inform the tenant about the reasons for the increase and the possibilities of challenging it. The handwritten signature serves only to identify the declarant and is not a mandatory requirement, as long as the identity is clarified in another way.
Since in the present case there was no uncertainty about the sender of the rent increase and both parties had accepted the increase without objection over the years, it would be an abuse of rights if the tenant…