It has the Mouse Studios embossing stamp, guaranteed authentic. A rare piece of Rick Griffin's work, very collectible and bound to increase in value. Please, if you have any questions or concerns about this item, do not hesitate to contact me. I work hard to be accurate in my descriptions, I think my feedback's reflect this.It is signed & framed as well. The item "Rick Griffin Grateful Dead Surfing California Artist Proof S/N" is in sale since Friday, August 19, 2016. This item is in the category "Entertainment Memorabilia\Music Memorabilia\Rock & Pop\Artists G\Grateful Dead\Posters". The seller is "discountdoug" and is located in Nevada City, California. This item can be shipped to United States.