Principles of European contract law: an autonomous lex mercatoria or part of a universal lex mercatoria?

The Commission on European contract law contends that the principles of European contract law are a source of European lex mercatoria. The concept of lex mercatoria itself, however, is still ambiguous. This paper analyses the current academic opinion on the nature of lex mercatoria and provides a more practical definition which focuses on the role of the arbitrator and better clarifies this confusing system of law. It further explains how the PECL, like any other set of principles developed to regulate international trade, form a part of the universal lex mercatoria.