Hard to tell from the pic, but most likely a mark in the planchet that wasn't obliterated when struck. Very common on clad Ikes.
Over the years, I have seen some very sloppy grading for modern coins. Quite often MS and PR-65 have not been good enough for me. I often have to go up to PR-66 and 67 to get what I want. Back in 1999, when the State Quarter series started, a dealer I knew at the shows got a bunch of PCGS graded MS-65 Delaware quarters to sell. They looked like the coins in my pocket to me, but he was getting $40 apiece for them. Sure enough, one of his customers showed up ready to tear him from limb to limb at one of the later shows. That put an end to his certified State Quarter sales promotion.
It might be hard to tell, but as I view it, it seems to be clearly post-mint damage of some form. Its a good deep scratch.
why not? If it is intentionally mutilated with a knife, that might be a grade with details. This looks like a normal scratch from the coin being dropped while in a bag of coins or something.
Interesting that the customer wanted to tear him limb from limb..... I would have pointed him to the PCGS table and told him to have a nice day.