I wonder if this is ASIN-recycling (where ASIN is the product id), or simply a bad indexer. For instance, is it that an ASIN in location A is reused in location B? Is it that the ASIN is recycled by the lister/Amazon to maintain positive review percent on a new product? Or is it that the column(s) used to map the international comment thread to the product are incorrectly specified?