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At present, we assume that the seller uniquely identifies an object by means of a distinctive string of characters, e.g. by an internal item number or EAN code.
Conceivable Conceivable in addition to the item number, though, is a need for further information such as clothing size or colour to identify an item. The ItemIdentificationType element type is also suitable for these cases. However, we will not define detailed rules for this until a practical requirement for it arises.
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