The authenticity can be verified on Beckett Authentication Services website. This Autographed Card with the inscription of "Dr. 21B Only Takes Blue Cross (Hamill), 21B (Delk)" has been Personally Signed by Mark Hamill & Denny Delk of Star Wars. This item is 100% Authentic, it comes slabbed and authenticated by Beckett Authentication Services. The authenticity can be verified on Beckett Authentication Services website.