Rules of origin determine product nationality and control eligibility for preferential tariffs and trade remedies. Rules of origin set the criteria to determine a product's national source and serve as the legal mechanism for conferring preferential tariff treatment, imposing quotas, and applying remedial trade measures such as antidumping and countervailing duties. They also support trade statistics and country of origin labelling. Historically, under earlier GATT practice each contracting party independently prescribed origin criteria and could maintain multiple rules according to regulatory purpose.