I tried this one once at PCGS and now one last time at NGC. It's a problem coin according to the pros, but not to me, DARN IT! Just got the result this morning.
looks good to me, do see some scratching between bust and date on obverse. I would guess they gave AU details,cleaned maybe?
Discoloration due to corrosion. Otherwise, it is a planchet defect filled w/black debris. Also note glue residue (yellow-orange) base of shield & around leaves. I'm going to bet that the upper reverse has been altered/repaired to hide something. C-B-D will possibly let us know. At the least the TPGS's weaseled out and called it cleaned.
Could it be a slag error?... Get a toothpick and gently glide the tip across it. Does it feel smooth like its embedded in the surface or does the toothpick jump up and over it like it's on top of the surface?
Curious to see what they both said, and I'm assuming they both said the same thing, but I'm gonna guess altered surfaces.
I got dinged on one because of a planchet flaw once, and it had a similar black mark as what I see by the claw, although more unsightly. Sometimes there is evidence of someone having tried to mechanically remove the inclusion, so the presence of one will alert graders to look for other problems there. Liberty's cheek almost has "That Look" to it, which would probably be more readily visible in hand when you can tilt the coin around a bit or use a glass. Curious as to how the problem was described.
Awesome looking coin, don't listen to those amateurs. This is the one I have (love this type and all Capped Busts in general):
I suppose if both grading services says there's a problem, more than likely there is one. But it is a nice looker, regardless.