Buck does sell factory blems, but they no longer mark them on the blade or anywhere on the knife with FB like in the past. They're marked as blems on the box only which makes no sense to me. Below is from an earlier thread on that subject.
"No more "Factory Blem" markings?
There's a seller who recently added this to their description for factory blems that they sell. The seller has a great reputation, seems to have a good connection with Buck and sells hundreds of their knives. I've bought a bunch from them with never an issue. I recently bought a FB from the seller and true to his statement, it was only marked FB on the box and not the knife.
"According to Bucks recently changed policy, this knife is not etched with the "FB" (factory blemish) marking as has previously been on blades. Because all factory blemished knives are covered for structural or functional problems by Bucks Forever Warranty, they have decided to discontinue marking blemished knives. The only essential policy change is that no Buck knife can be exchanged because of a cosmetic blemish, from now on, without the original receipt. Otherwise, the best part about this change is that your blade will not have the unsightly "FB" on the blade (the box will state "Factory Blem"). We will ALWAYS let our customers know when a knife that they are bidding on is a factory blemish."
The grind on yours is not unique. The grind at the serrations on my Endeavor is the same as the one on your SentrY and the catalog shows it just the same as your factory pict.
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