Graded Sports Cards are cards that are evaluated by a third party company for their authenticity and condition, and are then sealed in what we call a "slab" to preserve this condition and prevent tampering.

 

There are mainly four sports card grading and authentication services which deserve attention and are reputable : The PSA, BGS, SGC, and GAI.

 

Professional Sports Authenticators (PSA): PSA pioneered the graded sports cards grading industry. They're part of Collectors Universe, a publicly traded Nasdaq company. You will however need a membership to take advantage of their grading directly. They use a 10-point scale and just recently added the half-point scale in their grading system (7.5, 8.5...) 

 

Beckett Grading Services (BGS): The BGS is affiliated with Beckett magazine and also uses a 10-point scale with half-points. What makes BGS unique is that it also offers a secondary rating for centering, edges, corners and surface. Many people believe the BGS scale is graded more strictly than the PSA scale. BGS also offers their BCCG grading service, a more economic service than the BGS one, which is looked down from many collectors who don't see a BCCG graded card as something as professionaly graded as a BGS one.

 

Sportscard Guarantee (SGC): SGC is another reputable grading service out there. The SGC grading scale starts at 10 (poor) and goes up to 100 (pristine).

 

Global Authentication, Inc. (GAI): This grading company was started by two former PSA employees and bring a lot of that prestige with them to this new company.

 

Any other grading company out there is trying hard to get their share of the market, but unfortunately a lot of them where shady businesses from the get go and it's getting really hard to be considered as good and authentic as these four grading companies, with the possible exception of KSA, which is a Canadian grading company and is well respected in the collector community, especially in the Hockey sports cards grading.