Reservations and the CISG: The Borderland of Uniform International Sales Law and Treaty Law After Thirty-Five Years

Abstract

The makers of uniform international commercial law have traditionally used an instrument of public international law – the treaty between States, or ‘convention’ – in order to unify commercial law rules governing the relations between private parties (merchants). The resulting ‘dual character’ of such conventions as creatures of both treaty law and private law gives rise to a host of difficult legal questions. Maybe more than by any other type of legal rules, such questions are raised by reservations, i.e. formal declarations by which States ‘opt out’ of certain provisions in uniform law conventions, leaving it to the courts to determine the precise effect on contracts between private parties.The 1980 United Nations Convention on Contracts for the International Sale of Goods (CISG) ranks as one of the most successful uniform international commercial law instrument of all times, having been ratified by 83 States worldwide, among them the U.S., 24 of the 28 EU States, Brazil, Russia, China and Japan. The present article takes the 35th anniversary of the CISG as an occasion to provide an overview of the experiences that have been made with reservations thereunder, investigating the various difficulties that the dual character of its reservations has caused in theory and in practice.In doing so, the article first discusses the hotly disputed qualification of some of the CISG’s provisions as ‘reservations’ or mere ‘declarations’, and its legal consequences. It then challenges the commonly held perception that reservations reduce the degree of uniformity under international commercial law conventions, arguing that reservations should be regarded as a tool enabling a ‘wider’ uniformity. The article goes on to address problems that have emerged in practice under the CISG, as notably the tendency among courts to overlook reservations and the significant uncertainty they seem to cause both in the eyes of government officials and – maybe more importantly – of judges and arbitrators deciding cases. Finally, it looks forward to the next 35 years and discusses the (likely) rule of reservations in future CISG practice, including the trend to withdraw reservations, which reservations may be here to stay and which may even gain in importance in the future.In summary, the article presents the most comprehensive treatment yet of reservations under the most important uniform international commercial law convention in force, identifying important lessons to be learned for the unification of commercial law in general.