49 Ariz. St. L.J. 1257 (2017). Alan L. Durham.
Because a patentable invention must be novel, and it must embody an advancement that would not have been obvious to persons of ordinary skill, the invention must be compared to the “prior art.” Prior art, in the language of the current Patent Act, includes anything that was already “patented, described in a printed publication, or in public use, on sale, or otherwise available to the public.” With certain qualifications, patent law has always required that prior art have been available to the public. A manuscript describing the claimed invention that had never left its author’s desk drawer would not qualify as a printed publication. But what of prior art that was accessible, but ignored; or that was available at one time, but snatched away or forgotten? Can “lost art” be used to challenge the novelty of a claimed invention? It is an important question because of the light it sheds on what it means for prior art to be “available to the public,” a matter that has been the subject of much attention since the recent adoption of the America Invents Act. It also forces us to consider the character of the public domain as applied in the context of patent law; specifically, whether every addition to the prior art is also a contribution to the public domain and, in consequence, irrevocable. I conclude that courts should be guided by the policy of preserving in the public domain advancements that have already made an enduring contribution to public welfare. Lost art that demonstrably failed to provide any lasting benefit to the public should not count against a later inventor who, in a practical sense, has advanced what the Constitution calls “the Progress of . . . [the] useful Arts.”