General Terms and Conditions, short GTC, also just «General Terms» are contractual clauses that a party formulates and applies generally to all its business relationships or at least to a specific business area. Thus GTCs serve on the one hand to rationalise, but for smaller companies GTCs can also serve as a checklist. This means that once you formulate your General Terms, you may even consult a lawyer for this purpose, and then you no longer have to ask yourself what you should agree on every time you conclude a business transaction. However, GTCs also have an important function in negotiations. If you enter into contract negotiations with your own ready-made contract clauses, you have a good chance of enforcing them in the negotiations (contract dominance), if only because many people think that GTCs cannot be changed. The latter is of course not true. GTCs can always be changed by individual agreements.
From a legal point of view, it is even assumed that the other party to the contract does not read or read but does not understand the GTC at all. For this reason, two special rules are applied to GTC. The ambiguity rule is based on the principle of good faith (Swiss Civil Code, CC 2) and is generally applied in contract law. The rule states that ambiguous clauses, in this case in the GTC, are interpreted in favour of the party who must adopt the GTC and to the disadvantage of the party who uses them (latin also: in dubio contra stipulatorem). There is also the rule of unusualness. According to this rule, provisions in the GTC are non-binding for the obligated contractual partner if this contractual partner did not have to expect a provision that is unusual for the respective transaction.
Logically, GTC must be presented to the other contracting party before the conclusion of a contract (CO 1). It is best to attach the GTC to the offer. The presentation of the GTC together with the invoice would be clearly too late.
Nowadays, it often happens that both or more parties to an agreement have their own GTCs which they want to apply in the contractual relationship. However, this is not advisable. The so-called «Battle of the Forms» can occur if the GTC are contradictory. The solution is to take one set of GTC and adapt it in an individual contract to the acceptable wishes of the other party/ies.