Independently authenticated through Beckett (Lautner) and Celebrity Authentics (Pattinson) with witnessed certification. This type of witnessed authentication sticker is only placed on items that a Beckett/CA representative witnessed being signed and is stickered immediately.
(Think of it as a notary public where the authenticator is confirming they witnessed the actual item being signed by that actor). Certification numbers are unique on each individual item.
While extremely rare, an item could sell on one platform and also sell on another platform before inventory updates. Items are transported to and from signings and handled by the signers so minor wear is normal.