Hi @blueeyespt , welcome to the forum. To answer your question quickly, every 3rd party grader has their own definition of ‘Mint’ in terms of conditional attributes. You are correct in that surface dents normally will get a card knocked down to a PSA 6 depending on severity when graded by PSA. Also it’s very hard to tell in that small photo, but could it be possible those are small print dots and not actual physical dents?
According to the SGC website it states:
GRADE
9
QUALITY
MINT
DESCRIPTION
60/40 or betting centering, sharp focus and four sharp corners*. A minor flaw may exist upon close examination. A minor flaw may be, but is not limited to: a slight nick to one corner, a small gloss break or surface scratch, a minor print line or minor refractor line, a minor focus or color imperfection, or a small print spot.
You may want to verify if it’s a physical dent or just a small printing imperfection, perhaps the seller could verify this for you.
Anyway… SGC 9, 9.5s and 10s are generally pretty solid cards they just don’t command the premium that PSA does in the Pokemon hobby normally. If you can confirm those are physical dents you may want to seek out a PSA 9 copy of the same card even if it costs a little more, in my experience they are a very consistent grading standard and will maximize card value in the Pokemon hobby.
For more info you may also want to ask your question here:
www.elitefourum.com/t/the-giant-professional-grading-thread/30930/1