Abstract. A certificate of authenticity (COA) is an inexpensive physical object with a random and unique structure S which is hard to nearexactly replicate. An inexpensive device should be able to scan object’s physical “fingerprint,” a set of features that represents S. In this paper, we explore the requirements that optical media such as DVDs should satisfy, to be considered as COAs. As manufacturing of such media produces inevitable errors, we use the locations and count of these errors as a “fingerprint” for each optical disc: its optical DNA. The “fingerprint” is signed using publisher’s private-key and the resulting signature is stored onto the optical medium using a post-production process. Standard DVD players with altered firmware that includes publisher’s public-key, should be able to verify the authenticity of DVDs protected with optical DNA. Our key finding is that only DVDs with exceptional wear-and-tear characteristics would make optical DNA an ine...