How does Balenciaga's serial number system work? Do bags of the same style and color have the same serial number? Or each serial number is unique to a particular bag? I saw a bag (Balenciaga Day Electric Blue) for sale at bagpassion.com that has the same serial number as a bag (same style) for sale in another site. Is it possible that both are authentic? Or is it more likely that one of them is fake? I am under the impression that both websites sell only authentic items so I'm quite confused here. I provided links to the website for your reference. Thanks a lot in advance!