Classification should begin with the named headings — oysters (03631) and fresh cuttlefish, octopus, and squid (03633) — and only default to the NES heading (03635) if the species is not covered there. Abalone, geoduck, clams, mussels, and scallops in fresh or chilled form would typically fall here. When in doubt, a binding ruling request to CBP or consultation with a licensed customs broker is advisable.

Geoduck clams harvested in the US Pacific Northwest are subject to state-level harvest licensing and size limits, but imported geoduck from Canada or other sources must meet FDA NSSP-equivalent certification for the harvest area. Some Pacific geoduck is also subject to state shellfish dealer certification requirements upon entry into domestic commerce. Importers should verify both FDA admissibility and destination-state requirements before arranging shipment.