This baseball is signed by Joe Mauer. This is authenticated by Steiner SportsThis baseball comes complete with the Steiner Sports certificate of authenticity and tamper proof hologram.MONEY BACK GUARANTEE! If for any reason you are not completely satisfied with the quality or authenticity of your purchase, we will gladly give you a full refund or exchange, whichever you prefer up to 30 days after purchase. Please feel free to e-mail us with any questions. GOOD LUCK BIDDING!!! Authenticator Pre-Certified Authenticator: Steiner Sports Authenticated History of item: Joe Mauer signed this item in the presence of a representative from Steiner Sports. Describe how you came to possess this item: Super Sports Center is a fully authorized dealer for Upper Deck Authenticated as well as Mounted Memories and Steiner Sports. Other information about you and / or the item: Super Sports Center strives to deliver the most authentic in sports memorabilia from trusted companies like Mounted Memories, Steiner Sports and Upper Deck Authenticated. If it exists, we can find it for you!