Section 5(1)(b) in The Customs Tariff (Determination of Origin of Products under the Duty Free Tariff Preference Scheme for Least Developed Countries) Rules, 2015
(b)the product has undergone a change in tariff classification in sub-heading at the 6 digit level of the Harmonized System nomenclature from the tariff classification in which the non-originating material used in its manufacture are classified; and