Let's put it this way. There's the Original Manufacturer (Sony, Samsung, LG). Then there's the Re-Wrappers (Efest, MXJO, AWT, Imren) who use the B grade cells from the OEMs, and re-wrap them with over-inflated specs. Then there's the little guys (people in basements and garages and whatnot), just trying to make a quick penny, who take any cell they can get their hands on (any grade cell, B/C/D) and put fake wraps of them. Since all these Re-Wrappers are pretty much of Chinese origin, it makes it difficult to distinguish "fake" re-wraps apart from "real" re-wraps.
Although the Re-Wrappers use over-inflated specs, they are still quality cells that can be used safely, just not at what the wraps rating says ("Authentic" re-wraps consistently measure out to 20A cells, which are usable in most Regulated devices without issue)
Since these little guys have started to become a bigger part of the picture, the Re-Wrappers have taken a further step by putting on Authenticity codes/stickers, which will confirm if the cell was actually re-wrapped by them, or by the little guys. If a battery were to fail the Re-Wrappers authenticity, I would chuck it immediately, not even use it in a flashlight. If it passes, then I would only use it in a Reggy.
It's still recommended to only use cells from OEMs (Sony, Samsung, LG)