This jersey was worn and hand-signed by Joanna Jedrzejczyk. It is officially licensed by the UFC and comes with an individually-numbered Certificate of Authenticity from Fanatics Authentic. The Certificate of Authenticity is signed by the UFC. To ensure authenticity, the item can be verified online using the Certificate of Authenticity's unique alpha-numeric code. This process helps to ensure that the product purchased is authentic and eliminates any possibility of duplication or fraud.