This baseball has been personally hand-signed by J.D. Martinez with the inscription "18 WS CHAMPS." It has been obtained under the auspices of the Major League Baseball Authentication Program and can be verified by its numbered hologram at MLB.com. It also comes with an individual numbered, tamper-evident hologram from Fanatics Authentic. This process helps to ensure that the product purchased is authentic and eliminates any possibility of duplication or fraud.