Dummy UPC

Dummy (number system 4) UPCs are for private use. This means anybody (typically a retailer) that needs to assign a UPC to an item that doesn't already have one, can use any number system 4 UPC it chooses. Most importantly, they can know that by doing so, they won't pick one that may already be used. So, such a UPC can and does mean something different depending on who you ask, and there's no reason to try to keep track of what products these correspond to.