Excerpt: "The way it works is roughly like a serialization or UPC code. The brand buys the codes from Amazon and puts a unique code on every unit it creates for sale on Marketplace. All the codes are serialized; Amazon will not accept items without codes."

If they signed products with a cryptographic key, might actually be worth something as proof of who they are.

Manufacturer has a keypair. They include a QR code that's the digital signature of the combination of your name & the product's serial number. You use their public key to verify

A solution like this would also limit alienability of property. I buy a DSLR and register it with the manufacturer. Two years later I want to resell it to someone else and discover my manufacturer either refuses to issue the new QR code to the buyer, or wants to charge a "reasonable" or "nominal" fee of 25% of the fair market value of the good to effect the transfer.

This is why a distributed-trust solution like blockchain actually might not be overkill, in spite of its buzzwordiness these days.

Or to return to your idea, instead of the person's name, transfer to an ID that's backed by another keypair. The buyer now has the authority to sign away full ownership without asking the manufacturer for cooperation. Of course, this means the manufacturer and each seller in the chain now has to have a tech-support department for people who lost their private keys or forgot the keychain password....

Nope

https://medium.com/@alitech_2017/blockchain-based-qa-the-end...