Featured is a Thomas Wilson signed Back To The Future Biff Tannen Funko Pop. This Pop was hand signed by Thomas Wilson and authenticated by JSA authentication services. Included with the figure is a JSA hologram and certificate of authentication. This item would make a great addition to any entertainment memorabilia collection. 100% Guaranteed Authentic Autographs. Sign up for our Sports Integrity Newsletter for deals and upcoming autograph signings! Sign up to receive special insider notifications of deals and upcoming autograph signings! Tom Wilson Signed Biff Tannen Back To The Future Funko Pop #963 JSA. James Spence Authentication (JSA). Questions about this item? My about us text goes here. My authenticity guarantee text goes here.