美国法律
The PECL were inspired by the United Nations Convention on Contracts for the International Sale of Goods (CISG) from 1980; however, they are a so-called "Soft Law", such as the American Restatement of the Law of Contract, which is supposed to restate the Common Law of the United States. Therefore, the PECL do not represent a legally enforceable regulation: "The term 'soft law' is a blanket term for all sorts of rules, which are not enforced on behalf of the state, but are seen, for example, as goals to be achieved."