Importers should verify current antidumping and countervailing duty orders with US Customs and Border Protection and the International Trade Commission, as trade-remedy coverage for specific organic chemicals can change. The origin of the shipment is critical, since orders are country-specific. A licensed customs broker can run a scope ruling check against active orders before importation.

Lines 2918296500 and 2918297500 separate compounds that are described in Additional US Note 3 to Section VI from those that are not. Note 3 typically covers certain chemical intermediates subject to a special duty regime. Correctly identifying whether a specific phenolic carboxylic acid falls within the Note 3 definition requires reviewing the note text and, if necessary, seeking a binding ruling from CBP, as the duty implications can differ materially between the two residual lines.