Certified Guaranty Company, also known as CGC, is a Sarasota, Florida comic book grading service. CGC is an independent member of the Certified Collectibles Group of companies. It is the first independent and impartial third party grading service for comic books. The company was launched in early 2000 and has since gone on to become a notable part of the comic book collecting community. As of 2021 they have graded over 7 million comic books.