General terms and conditions
General terms and conditions (“GTC”) are contractual clauses that a market participant pre-formulates for a large number of similar transactions (e.g. the sale of products, provision of services, etc.). They are particularly common where a market participant concludes numerous identical contracts in writing with its customers. In order for GTCs to be validly agreed, the customer must have the opportunity to take note of them before the contract is concluded. This usually occurs by explicit reference to the GTC.
In order to protect the weaker contracting party, case law has developed in particular the unusualness and ambiguity rules to avoid unfair results. The unusualness rule prevents clauses of the GTC from becoming part of the contract which the disadvantaged party did not expect and did not have to expect in the specific contract. The ambiguity rule in turn stipulates that in case of doubt, ambiguous provisions of the GTC are to be interpreted to the detriment of the author of the GTC.