Always post here first. There are a lot of styles and details that don't fit any specific category, and there are a thousand more exceptions and "if's, and's and but's" than anyone could ever have room to describe in a few-thousand word Guide.
Daria48's Guide breaks fake numbers down by Always Fake and Possibly Fake, but there's also a remote chance that someone doing the stamping simply made a mistake, and we need to take a close look at the bag.
The ones you can report immediately are the ones with a serial number like that one - only 5 digits or that says Made In Korea, or the ones with only a 2-digit prefix at the top of her List like NT-4903. Those are always fake.
Also note the Edit I made to my original answer:
"BTW, if the seller removes the fake hangtag and the name Coach from the listing description it would actually be legal to sell since other than the hangtag, it doesn't seem to say "Coach" anywhere on the bag. The creed just says "This is a Leather Ware bag..." which isn't a copyright violation."