Coke derived from coal, lignite, or peat falls under heading 2704, while petroleum coke — a byproduct of oil refining — is classified under heading 2713. The feedstock origin is the key distinction: coal-based carbonization products go to 2704 regardless of their physical form.

Certain coke and semicoke imports have been subject to antidumping or countervailing duty orders depending on origin country and product specification. Importers should check the current scope of any active orders with CBP and the Department of Commerce before shipment, as coverage can be product- and country-specific.