0309.10 - Of fish:

This HTS category, 0309.10, specifically covers flours, meals, and pellets derived from fish, provided these products are fit for human consumption. This implies that the raw material is exclusively aquatic vertebrates from the fish family, processed into a powder, granular, or pelletized form. The classification hinges on the origin of the aquatic invertebrate and its suitability for direct human intake, distinguishing it from industrial feed or by-products.

The sibling category, 0309.90, encompasses similar processed aquatic invertebrates but explicitly excludes fish. Therefore, if the processed product originates from crustaceans, molluscs, or other aquatic invertebrates that are not fish, it would fall under the "Other" designation of 0309.90, rather than the fish-specific category of 0309.10.

Under 0309.10, further subdivisions are provided to refine classification based on packaging. The subcategory 0309.10.05.00 applies to goods presented in bulk or in immediate containers where the combined weight of the container and its contents exceeds 6.8 kilograms. Conversely, 0309.10.90.00 covers all other presentations of fish-based flours, meals, and pellets fit for human consumption, including smaller packaging.