Correct, they have one line. Some of the items come off the line and are sent to Nikon USA, others to Nikon Japan, others to Nikon Europe. If an American has one that went through some subsidiary other than Nikon USA "without a legitimate reason," Nikon punishes them. The "legitimate reason" is there because there are a few cases where this is acceptable to Nikon. For example, if you're on vacation in Paris, walk into a shop that's an authorized Nikon Europe retailer, you're technically fine. You purchased through Nikon's desired channel. Of course, you need to be able to *prove* that this is what happened, or they will punish you just the same...
In particular, there's a detail that's worth mentioning. The big New York suppliers (I'm thinking of B&H and Adorama but there might be a couple of others big enough) do provide warranties and even extended warranties, so you are fine within those periods of time. If necessary your lens / camera will be replaced, and they both have a history of doing this. But Nikon USA will NEVER work on an item that they deem to be grey - ever. Even if you pay for it, even if it's after the nominal Nikon warranty period. Note that I used the word "deem." Nikon has an incredibly user hostile policy on this that particularly grates on American sensibilities: you are assumed guilty until you prove otherwise. If you have a product that appears out of its normal context - let's say it's that lens you bought in Paris as described above - Nikon assumes it's grey market unless you demonstrate to their satisfaction that YOU were the importer that bought from Nikon Europe, rather than (say) Adorama, who then sold it to you. This means in practice that you'd better keep every one of your receipts FOREVER. Because ten years from now, if they screw up their records and can't figure out which subsidiary they sold the lens to, they will assume that it's grey and will refuse to service it.
Some lenses have the subsidiary encoded in the serial number, for example many of them now have "US 3230201" or similar.
Until recently I was just fine buying grey market stuff. I strongly dislike Nikon's user-hostile policies, as well as their snail-like repair turnaround, so I now refuse to use Nikon repair unless I'm forced to. In my experience, the authorized repair depots do just as good a job, will turn the repair around FAR more quickly, and they'll - shock - even tell me what the situation is. But this year Nikon has shown that they're trying to cut off even that avenue, by refusing to sell parts. For a while it was even trivial parts like battery covers, although this particular absurdity has been reversed at the moment. I'm confident that older, simpler things like, say, the 50/f1.8 AFD or even the 200/f4 Micro-Nikkor will probably always be serviceable, but if I were buying a 800/f5.6 AFS VR-II at $12k or even a D800e at $3000, I would reluctantly have buy a valid import.
By the way, Nikon also assumes you have no entitlement to warranty repair unless you prove that you do. Even if you've registered with them when you got the product. Proof usually means that original receipt. Even if, for example, the entire model is new enough that 100% of them must be within warranty period.
Honestly I'm angry enough about this that if it wouldn't cost me some huge amount of money, I would consider switching brands, but I checked into the Nikon customer motel thirty years ago and I can't check out. I guess it's like the Eagles said: you can check out but you can never leave...
_____ Brian... a bicoastal Nikonian and Team Member
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