When Patents Claim Preexisting Knowledge

Novelty is a basic requirement of patent law. An inventor cannot obtain a patent if the invention exists in the “prior art,” a term that generally refers to knowledge and technology already in the public domain. Interestingly, an earlier-filed patent document qualifies as prior art as of its filing date — even though the document does not become accessible to the public until much later. The rationale is that the first inventor did all that could be done to promptly disclose the invention to the public; administrative delay of public accessibility due to Patent Office procedures should not count against the inventor. That the first inventor placed the patent document in the pipeline toward disclosure justifies backdating it for prior art purposes. But an earlier-filed patent application is not the only type of “pipeline” disclosure. A manuscript submitted for publication in a peer-reviewed technical journal is also on a trajectory toward public disclosure. This Essay argues that patent law should not only treat such manuscripts the same as earlier-filed patent documents for prior art purposes, but that backdating is more justifiable for peer-reviewed publications. This Essay raises interesting theoretical and policy questions about novelty and the meaning of prior art