A database of serial numbers alone wouldn't be sufficient. Counterfeiters frequently copy real serial numbers and print them on fake products.
There are more effective means such as tamper resistant RFID tags, but those aren't cost effective for cheap items. And often no one bothers to check anyway.
Any individual labeling of goods is not cost-effective even on not-so-cheap items.
I've seen implementing individual labeling of items in two cases first-handed. Both were required by new regulations and both almost kill small companies.
Cost of new equipment (readers, dedicated computer which can work 24/7 in real world in the hands of non-IT people), IT system (you have only one vendor, of course, as it is government-required system, and you can imagine quality of this solution, as it is written by government contractor), support for this IT system and integration with existing POS and ERP (by 3rd party company), all these costs are tremendous in practice. If you are not reseller or distributor but producer, you need additional hardware (typically very expensive one) to apply tags to items on your production line.
Unique tags prices are negligible here.
I've seen this for small custom brewery (with very rudimentary bottling line) and for small imported/distributor of fine and exotic alcohol. Both companies are alive, but they were forced to get loans when implemented new regulations about individual-per-bottle tags, and it was long and painful process in both cases.
Who will pay for this? You. And me. In both ways: some business goes out (think: your nearest papa-n-mama grocery store, which struggles to compete with big supermarket chain already), and other business will rise up retail prices to cover expenses to implement supply-chain control systems. As there will be expenses on all steps from producer to retail store, these expenses will accumulate.
And we already pay (with taxes) for police. Which work is to catch thieves.
UPDATE: And as sibling comment (https://news.ycombinator.com/item?id=33740337) points out, it is not one-time expense for any business in supply chain, as they will need to scan all these tags, and have (much) more warehouse/retail space workers or pay more for more hours. Always, forever.
I think serial numbers would be enough to stop the vast majority of people selling stolen items.
It would require companies to track serial numbers that go into the store, and serial numbers of items put on shelves, or otherwise legally leave the store. After a while, it'll be clear which items & serial numbers were legelly sold vs. stolen. And, to address the original point, copied stolen serial numbers still aren't any good.
The serial numbers of stolen items get reported to the authorities and/or Amazon, and it becomes their legal problem. As another post in this thread poins out, pawn shops have to do something similar to check for stolen items. So there is some sort of legal framework in place.
Im not saying that this should be i plemented or anything, I'm just trying to say that individual serial numbers might work. It will not be easy to implement, and cost money. But so does rampant theft. Maybe it's worth pursuing.
It’s hard enough to get them to unload you when all they have to do is count pallets like “yep, 22 pallets of potatoes” even harder when they have to break down pallets to count individual cases and would be impossible if they had to verify every single item by serial number.
Even when I used to deliver to individual grocery stores it was difficult because they didn’t plan for unloading the truck on the schedule and they had to stock the shelves before the store opened so more often than not they just got their stuff off the truck as quickly as possible without even doing any sort of verification, just pull the pallets with their store number and let the department heads deal with it in the morning.
It sounds like a valid idea but the amount of labor would be astronomical.
Attorneys General, likely. Amazon would be found selling stolen goods, told to clean up, they wouldn’t, and there’d be a kerfuffle and suddenly it would be one of the items that is harder to list (try listing Milwaukee cordless equipment on Amazon now for example).
This is what happens (in theory) with GSM mobile phones. GSM devices have a serial number in the form of an IMEI which can be blacklisted from networks if stolen [0]. There are, of course, still ways round it as detailed in the wikipedia entry - e.g. the blacklists are national ones, and organised groups can "just" ship the phones to another country and sell them there.
Even so, as you intimate, it does make it _harder_ to resell stolen phones.
