Stephon Marbury Signed New York Knicks Wilson Indoor/Outdoor NBA Basketball

Authentication

Certified by an independent third party

We do not authenticate our own inventory. Signatures are examined by an outside authentication house — PSA/DNA, JSA or Beckett Authentication Services — and the certificate they issue travels with the piece. Autograph authentication is an opinion on whether a signature is genuine; it is a separate service from condition grading, which assigns a numeric grade to an item’s state of preservation.

How authentication works, in full