Here is why your ideas don't work

I buy a Rolex. I drop it. It stops running. I take it to my local watch battery place. They take it in, say they'll take a look at it. They call me back an hour later, say "sorry we can't service Rolexes" and now I have to take it to Rolex. Meanwhile they've photographed the shit out of it and sold the serial numbers to a shop in Shenzen.

A month later my legit serial number is on 900 counterfeit watches, a dozen of which are seized. Rolex is notified and blackballs my serial number. Now - maybe I get my watch out of there before Rolex decides its counterfeit and I get blackballed next time. Or maybe Rolex decided they sold me a fake Rolex and either refuse to work on my Rolex or confiscate it. Either way, I'm a legit customer paying legit money for a Rolex and you just called me a criminal. This will not end well for you.

So okay. You put three serial numbers on the thing to get "10^18 possible combos." Great. My shady shop either copies all of them, or one of them stays secret so that the only way you can tell a counterfeit Rolex is by dismantling it all the way.

All right, though, you've got a magical mystical database, the tech nerd's solution to never touching that shitty Bitcoin bullshit. Every authorized Rolex repair shop has to have access to it, and there needs to be a process whereby they can influence it - if they find a fake Rolex and the serial number comes up real, there needs to be a process whereby a field-reported serial gets disavowed. These are trade school grads at best, BTW, many of whom are in their 60s, and you've decided you need them to keep a computer around, learn a system and also be responsible for pissing off their best customers.

So we've got a disavowed serial number but the watch is being serviced by a savvy center that knows it's legit - they unpeel down to your mystical third serial number or some shit. THAT watch is legit. It needs to be marked in the system. Do we give the owner a new serial number?

And what happens when your counterfeit ring gets access to your database? 'cuz they're gonna get access to your database.

And what happens when the write keys get hacked/leaked? Swiss banking security largely functioned through SneakerNet and we've got the most recognizable brand in the world with a dealer network nearly 2000 strong and they are fallible.

Here's what works

You've got a watch. It's got a serial number. That serial number is tied to an NFT on a blockchain. When you buy that watch you get set up with a passcode - maybe it's a password, maybe it's your driver's license, maybe it's your wedding anniversary, whatever. And when you bring it in for service, that passcode combined with that serial number allows you to operate on the blockchain. NOTHING ELSE DOES. And when you sell it, you transfer ownership - via the blockchain - to the new owner, who gets a new passcode, who gets to interact with the blockchain instead of you.

- Rolex has to do nothing.

- The dealer has to do nothing.

- You have to use your digital signature.

- And we're done.

How much premium does Nike lose on the black market? I don't have to wonder, I know. Thirty to eighty percent.

Read that again.

Thirty to eighty percent.

There isn't much out there that covers the black market. Piketty reported every estimate he could find and the overall black market is estimated to be between 50% and 150% that of the white market. Michel Chivalier reported it at "thirty to eighty percent" depending on the business, the market segment and the year; he did that based on being chairman of Paco Rabanne and then researching and writing four books on the subject.

Yes. It is difficult to suss out quality counterfeit goods. So you can either turn your dealer network into a cryptographic Stasi hell or, you know, do what the industry is already doing.