 Although satisfying rules of origin in principle means that a product has qualified for the originating status, and is thus entitled to preferential tariffs, in most cases, a claim for preferences must be accompanied by a certificate of origin presented to the customs authority at the port of entry.Unlike the exporter or manufacturer, who is responsible for (and capable of) proving to the issuing authority (or self-certifying) the origin of the product, the importer often has little knowledge of how the product meets the origin criteria.The importer is instead required to present a proof, e.g., a certificate of origin issued or obtained by the exporter or manufacturer.