How do you authenticate baseball card?

Answer:

Have the card Graded

You could send the card to get graded by PSA, short for Professional Sports Authenticator PSA graded cards are sonically sealed inside a protective, tamper-evident PSA holder guaranteeing that the card is authentic. The card holder has a tagged label that shows its certification number, manufacturer, grade, date, unique bar code and player's name. This label appears above the card that is graded. To get complete information on their card grading standards, visit their website.
Contributor: Steven
First answer by Steven Keyman. Last edit by Steven Keyman. Contributor trust: 1623 [recommend contributor recommended]. Question popularity: 1 [recommend question].