Posted By:
Jay MillerScott--My guess is that the grading company will define a set any way people want for registry purposes as long as there are X number of collectors who show an interest. Ty Cobb cards could be a set. So could cards of players named Elmer if there was interest in that. I guess the only other factor would have to be that the number of cards in the set could be agreed upon so the grading company could judge completeness.