This Essay proceeds in three parts. Part I summarizes the King Pharmaceuticals opinion. Part II argues that the opinion was correctly decided, and it offers an original thesis about the role that the printed matter doctrine should play to enforce patentees’ disclosure obligations and preserve the deep structure of the Patent Act. Assuming that King Pharmaceuticals was correctly decided, Part III addresses the necessary next step in the continuing refinement of the printed matter doctrine. The Federal Circuit must explain why claims like the claim at issue in Prometheus Laboratories v. Mayo Collaborative Services are novel.Cite as Kevin Emerson Collins, An Initial Comment on King Pharmaceuticals: The Printed Matter Doctrine as a Structural Doctrine and Its Implications for Prometheus Laboratories, 2010 Patently-O Patent L.J. 111 at http://www.patentlyo.com/Collins.KingPharma.pdf.