2306 - Oilcake and other solid residues, whether or not ground or in the form of pellets, resulting from the extraction of vegetable or microbial fats or oils, other than those of heading 2304 or 2305:

Heading 2306 encompasses oilcake and other solid residues derived from the extraction of vegetable or microbial fats and oils. These materials are typically byproducts of the oil extraction process and can be found in various forms, including ground meal or pellets. Crucially, this heading excludes residues from the extraction of soybean oil (heading 2304) and ground-nut oil (heading 2305), which are classified separately.

The products within 2306 are distinct from other primary agricultural or foodstuff categories at the same level (Chapter 01-22) due to their nature as processed byproducts rather than primary commodities or finished food items. They serve primarily as ingredients for animal feed or other industrial uses, distinguishing them from edible oils or food preparations.

This heading is further subdivided to specify the origin of the oil extraction. For instance, subheadings distinguish between residues from cotton seeds, linseed, sunflower seeds, and those derived from rape or colza seeds. Other specific origins like coconut or copra, and palm nuts or kernels, are also individually listed. The residual category, 2306.90, captures oilcakes from other vegetable sources not specifically enumerated, ensuring comprehensive classification of these valuable byproducts.