CGC Trading Cards has developed a proprietary algorithm to determine a card’s final grade based on its sub-grades. While we can’t explain how we arrived at the grade and sub-grades for a specific card, we can share some guidelines. First, it is important to note that the final grade is not simply an average of the sub-grades. Rather, it is based on numerous rules built in to CGC Trading Cards’ proprietary systems and grading process. For example, the final grade can be no more than 1 point highe