The articles described or meeting the specified conditions set forth below are excepted from marking requirements (see subpart C of this part for marking of the containers):

Articles that are incapable of being marked;

Articles that cannot be marked prior to shipment to the United States without injury;

Articles that cannot be marked prior to shipment to the United States except at an expense economically prohibitive of its importation;

Articles for which the marking of the containers will reasonably indicate the origin of the articles;

Articles which are crude substances;

Articles imported for use by the importer and not intended for sale in their imported or any other form;

Articles to be processed in the United States by the importer or for his account otherwise than for the purpose of concealing the origin of such articles and in such manner that any mark contemplated by this part would necessarily be obliterated, destroyed, or permanently concealed;

Articles for which the ultimate purchaser must necessarily know, or in the case of a good of a NAFTA country, must reasonably know, the country of origin by reason of the circumstances of their importation or by reason of the character of the articles even though they are not marked to indicate their origin;

Articles which were produced more than 20 years prior to their importation into the United States;

Articles entered or withdrawn from warehouse for immediate exportation or for transportation and exportation;

Products of American fisheries which are free of duty;

Products of possessions of the United States;

Products of the United States exported and returned;

Articles exempt from duty under §§ 10.151 through 10.153, § 145.31 or § 145.32 of this chapter;

Articles which cannot be marked after importation except at an expense that would be economically prohibitive unless the importer, producer, seller, or shipper failed to mark the articles before importation to avoid meeting the requirements of the law;

Goods of a NAFTA country which are original works of art; and

Goods of a NAFTA country which are provided for in subheading 6904.10 or heading 8541 or 8542 of the Harmonized Tariff Schedule of the United States (HTSUS) (19 U.S.C. 1202).