The decision was made on the basis of a pre-formulated clause in a lease contract for shops in a shopping centre, which stated that all additional costs, in particular all costs arising from the operation and maintenance of the technical facilities, were to be borne proportionately by the tenant. Moreover, the clause contained a non-exhaustive list of the additional costs to be borne, which, among others, explicitly distinguished between the administrative costs, the lease costs for office space or administrative offices and the costs for the “centre management”, without defining in concrete terms which expenditures are exactly referred to.

The clause was declared to be ineffective due to insufficient transparency and certainty as such a formulation and breakdown aside the broad term “administrative costs” did not clarify which services were to be covered by the term “centre management”.

In order to include the expenditures for the “centre management” as part of the statement of additional costs in the future, which, by definition, are not to be added to the administrative costs, the measures covered should be expressly broken down in the lease contracts. An exemplary list with relevant positions would, as a rule, allow the allocation of these costs.

Since this decision is applicable to all of the existing lease contracts and tenants may now refer to the ineffectiveness of such clauses even if they have paid ancillary costs for years without objection, lease contracts should be completely revised, taking into account the adequate contractual structure and concretization.