1934-35 Jack Johnson & Jack Dempsey Signed Membership Card (JSA). Interesting High School Theaters Association of New York membership card signed by two of the most remarkable boxers to ever step into the ring; Jack Johnson and Jack Dempsey. Unique piece and professionally framed and matted, the signatures look incredible. Jack Johnson signature is dark and inscribed "Former Champion" while Dempsey simply wrote, "Good Luck." GD condition overall; comes with JSA LOA.