Lex mercatoria

Lex mercatoria or Law Merchant (‘LM’) is said to be the self-made law of international commerce. According to its proponents, LM is an autonomous legal order that not only supplements state commercial law, but works as a substitute for it. The ‘ancient’ LM, which accompanied the commercial revolution in late medieval Europe, is taken as a blueprint for ‘new’ LM, a transnational law that develops in international commercial arbitration to govern modern global commerce. According to its opponents, ancient LM as a uniform customary law of Europe never existed. Rather it was dreamed-up in order to support the neo-liberal agenda of new LM. This paper investigates the historical and empirical foundations of these claims in the three dimensions of transnational dispute resolution, norm making, and enforcement. It is concluded that truly autonomous transnational legal regimes are industry-specific exceptions, where socio-economic sanctions are formally organized. Transnational commercial law in general is characterised by a hybrid mode of governance, which combines institutions of private (norms, arbitration, and social sanctions) and public (laws, courts, and enforcement) origin. However, the latter are disembedded from their domestic context to a considerable extent.