Nikon likes to know what photo gear I have, so that have provided an online "camera bag" for me. When I obtain new photo equipment, I "register" it with them.
When I dropped a camera recently, the 24-70 lens that was on the cam, kind of separated into two parts. It's at APS in Chicago getting repaired. It's a big money repair, but that is a good lens. I had to have that lens for my photo work, so I purchased another used from Roberts. When I tried to register the replacement lens, Nikon broke the news regarding it's gray market identity. It's sort of ridiculous they won't "recognize" it. It was made by Nikon, in the Nikon factory, sold by Nikon. It was shipped to the USA in the wrong container, so they turn their back on it.
I notified Roberts about the issue. My contact there, Nick, said they had no way of knowing it was gray market. When I purchased it, I talked on the phone to a different salesperson, and got a one year warranty on it anyway. Nick said they would take care of any matters with the lens.
Does anyone know of a website that might list serial numbers so people can check for gray market gear?