Die Aufrechnung im Internationalen Privat- und Verfahrensrecht

Set-off in International Private and Procedural Law This paper analyses the functions of set-off, illustrates the differences between individual national regimes, introduces and explains Art. 17 of the Rome I Regulation (Rome I) and discusses disputes regarding further topics relating to the private international and procedural law of set-off. The primary function of set-off is the simplification of payment transactions. It facilitates the settlement of mutual claims of two parties against one another in a fast and simple way and reduces transaction costs by rendering unnecessary the execution of two separate payment transactions and by disburdening lawsuits from multiple claims. Given these – and other – functional advantages, no developed legal system can afford to abstain from providing the legal institute of set-off. Nevertheless, there are profound differences between individual legal systems, e.g.in the classification of set-off as a matter of substantive or procedural law, in whether there is a pre-condition of an offsetting statement, and whether the set-off has a retroactive effect back to the moment in which the two claims faced each other for the first time (ex tunc) or whether it just takes effect ex nunc after the issuance of an offsetting statement. European and international academic model rules (DCFR, UNIDROIT) basically follow the German-coined continental approach, with the exception of instead giving a set-off an ex nunc effect to a large extent. The regulation of the conflicts of law by the newly established Art. 17 Rome I is of fundamental importance given the differences between the legal systems. It declares as applicable the law governing the claim against which the right to set-off is asserted and abolishes former disputes about the applicable law. It aims at protecting the set-off opponent, which is justified since he is confronted with the extinction of his claim and the party who has pleaded the set-off, judicially or extra-judicially, had the choice to file a suit instead. The author argues that all known kinds of unilateral set-offs should be governed by Art. 17 Rome I, and that – irrespective of the scope of Rome I – all kinds of claims, contractual and non-contractual, should be subjected to its Art. 17 (analogously). Since Art. 17 Rome I does not regulate the law applicable to set-off by contract, the general rules of the law of conflicts apply, especially Arts. 3 and 4 Rome I. Furthermore, Art. 17 Rome I does not apply to genuinely procedural aspects of a set-off, so that the lex fori is to be applied. Heavily disputed is the question of the international jurisdiction of a court in respect to procedural set-offs against disputed, non-connected claims. Here, the author argues against international jurisdiction as a pre requisite since the set-off opponent is not deserving of any protection.