Custom and Law in Transnational Commercial Contracts: A Coevolutionary Perspective

The article examines the role of custom and trade usages in transnational commercial law. It distinguishes between state and communities-based rules. The validity of the former is grounded on procedural compliance, the validity of the latter on the effectiveness of the rule. It addresses the alternative or complementary nature of custom and law, accounting for the historical perspective. But for a few exceptions, custom and law are complementary and have co-evolved over time. Co -evolution has operated through different mechanisms: cooperation and choice. The analysis examines strengths and weaknesses of the two families of instruments that have permitted to feed law with customary rules.