Preferential origin rules: importers must declare origin and officers may suspend or disallow tariff preference pending verification. Chapter VAA requires importers claiming preferential duty to declare origin, possess and furnish information showing compliance with rules of origin and exercise reasonable care; a certificate of origin does not absolve this duty. Proper officers may request information, suspend preferential treatment, require security or deposit of differential duty to release goods, inform and seek information from the Issuing Authority, and restore or disallow preference based on responses. Preference may be refused without verification in specified circumstances and non compliance can lead to rejection of preference for identical goods from the same producer or exporter.