most of these third party graders have nothing third party about them, they are straight dealer to consumer sales so in my opinion they shouldn't be considered certified by a third party since there never was a third party involved in the grading of the coins. A dealer can get a coin in his inventory and look at it and say that is a MS-64 and he may be correct by the grading standards but that still doesn't mean it has any guarantee that is what it is like you have with third party companies and it doesn't matter if he puts his grade on a piece of plastic or on the 2x2 the coin is in when he got it its still not graded by a third party. A third party would be someone that has no interest in the outcome the coin grades and makes absolutely no more off the coin if it grades a P01 or a MS-67. In my opinion there are some self slabbers that get pretty close on some coins that are placed in plastic slabs by the dealer but still that doesn't mean it was graded by a third party company just because they happen to create some sort of special name for their grading service they provide for themselves