Author:Seymore, Sean B.
Position:In patent law


A bedrock principle of patent law is that the same invention cannot be patented twice. (1) Although improvements and modifications of the original invention can be patented, the identical subject matter cannot be claimed again. (2) For example, consider aspirin--acetylsalicylic acid--patented by Bayer in 1900. (3) Over a century later aspirin-related patents abound (including those for a nasal spray, chewing gum, and even a new method of making the drug). (4) But acetylsalicylic acid itself is no longer patentable--not by Bayer or any other party. (5) It has become public property. (6)

As a theoretical matter, this rule makes sense. The essence of the U.S. patent system is a quid pro quo between the patentee and the public. (7) The basic idea is that in order to promote the full disclosure of information about the invention to the public, the patentee must be given something in return. (8) What the patentee gets is the limited period of exclusivity conferred by the patent grant. (9) The public gets detailed knowledge about the invention as soon as the patent document is published (10) and possession of it at the end of the patent term. (11) So if an invention has already been disclosed in a prior patent, a subsequent inventor cannot give anything to the public that it did not already possess. (12)

Indeed, a fundamental principle of patent law is that a patent cannot issue if it would remove subject matter that is already in the public domain. (13) Patent law requires novelty; (14) meaning that an invention "must be new, that is, bestowed for the first time upon the public by the patentee." (15) So if the subject matter has previously been disclosed, the inventor has not invented anything and the public would receive no benefit from the patent. (16)

But the theoretical rationale for the proscription against repatenting rests on a crucial assumption--that the original patentee adequately disclosed the invention in the original patent. The patent statute requires that an invention be disclosed in sufficient detail to enable a person having ordinary skill in the art (PHOSITA) (17) to make and use the full scope of all that is claimed without undue experimentation. (18) The enablement requirement lies at the heart of the quid pro quo theory of patents because it ensures that (1) the applicant's disclosure sufficiently enriches the public storehouse of knowledge in exchange for the exclusionary right; (19) and (2) the public will get complete possession of the invention at the end of the patent term. (20) So when an invention is inadequately disclosed, the quid pro quo failed--the original patentee received a patent yet the public was deprived of an enabling disclosure.

Unfortunately, current novelty rules render an invention that was nonenabled in a prior patent unpatentable by a subsequent inventor who tries to claim it, even if the subsequent inventor has figured out how to make and use it. (21) This is true even though noncompliance with the enablement requirement is a persistent problem in patent law. (22) Policing enablement, admittedly, is no easy task; rejecting a patent claim for nonenablement might be the most formidable task that a patent examiner can undertake. (23) It is no secret that the U.S. Patent and Trademark Office ("Patent Office") routinely issues patents with nonenabled claims. (24) And when one considers the universe of millions of expired patents, (25) there is every reason to believe that some of them--perhaps many of them--contain nonenabled claims. Particularly suspect are patents emerging from fields like chemistry, biotechnology, and pharmaceuticals where a single patent claim can easily cover a large number of compounds.

This Article draws attention to a situation where a subsequent inventor--the reinventor--seeks to claim subject matter identical to that claimed by a third party in an expired patent. Under current patent law, the expired patent presumably issued with enabled claims. (26) I argue that if the reinventor can prove that the earlier claim to the subject matter was nonenabled (and thus invalid when the original patent issued), (27) the reinventor should be allowed to claim the identical subject matter in a new patent. (28)

To illustrate, consider the following hypothetical. Suppose that pharmaceutical company AcmePharma seeks to obtain a patent on a promising compound, X--a fibrate that effectively lowers cholesterol in humans. (29) At the time that AcmePharma files its patent application in 2015, X is, as far as AcmePharma knows, previously unknown. But when the patent examiner searches the "prior art" (preexisting knowledge and technology already available to the public) (30) to assess novelty, (31) the examiner finds an expired drug patent filed in 1980 that listed X by name and structure and claimed it along with ninety-nine other compounds. But the original patentee's disclosure merely speculated about Xs effectiveness as a drug (32) and offered no details about how to make X. But this inadequate disclosure of X was of no import to the original patentee who made a business decision not to pursue X--perhaps because it would be too costly to develop or another claimed compound proved to be safe, effective, and profitable. (33) Yet while X was discarded by the original patentee, the Patent Office did not give X much (if any) scrutiny during the original examination, thereby allowing the nonenabled compound to slip through the cracks (34) and to be covered by a presumptively valid (now expired) patent. (35) Importantly, X has never been commercialized; and other than the expired patent, no mention of X appears in the technical literature. Simply put, X was not invented until AcmePharma came along. (36)

Nonetheless, two major hurdles prevent the reinventor from obtaining a patent for X, even if the reinventor can actually develop and commercialize it. (37) First, the same invention cannot be claimed again in a later patent. (38) This double-patenting prohibition rests on the presumption that the original patent issued with valid (and thus enabled) claims. Second, the Patent Office can reject AcmePharma's claim to X for a lack of novelty despite its inadequate disclosure in the expired patent. (39)

To qualify as novelty-defeating prior art, the expired patent must satisfy three conditions. (40) First, it must predate the reinventor's filing date. (41) Second, the subject matter that the reinventor seeks to patent (X) must be identical to that disclosed in the prior patent (the "strict identity" requirement). (42) Third, and very importantly, the asserted prior art reference must be enabling. (43) This means that as of the reinventor's filing date, a PHOSITA could have combined the teachings of the expired patent with preexisting knowledge in the field to make X without undue experimentation. (44) If the expired patent meets all three criteria, it "anticipates" the reinventor's claim and renders it unpatentable for a lack of novelty because X is considered to be in the public's possession. (45) The U.S. Court of Appeals for the Federal Circuit (46) has held that, for the sake of expediency, the examiner is allowed to presume that prior art references are enabling. (47)

Thus, the reinventor's patentability hurdles are tied to enablement--a presumption that the expired patent issued with enabled claims and a presumption that the expired patent has an enabling disclosure. But the latter completely subsumes the former--if X is not enabled later in time when the reinventor files, it was not enabled earlier in time when claimed in the original patent. (48) Thus, I argue that if the reinventor can prove that the expired patent was nonenabling for prior art purposes, that proof rebuts both presumptions. The double-patenting problem disappears because the original, nonenabled patent was technically invalid. (49) The novelty problem disappears because a nonenabled reference does not qualify as anticipatory prior art. (50) Thus, AcmePharma can claim X in its own patent. (51)

The reinvention paradigm clearly aligns with broader goals of the patent system. A basic purpose of the patent system is to encourage investment in the research, development, and commercialization of socially valuable inventions that firms would not otherwise make. (52) Indeed, the possibility of reinvention--and ultimately securing a patent--might accelerate innovation by leading firms to engage in socially-productive races to figure out how to make and use the claimed-but-nonenabled subject matter contained in the universe of expired patents. (53) Returning to AcmePharma, it has determined X has value. If the firm is willing to invest time and money to prove that the original claim to X was nonenabled, AcmePharma will probably commercialize it. So reinvention would not only allow AcmePharma to recoup its research and development (R&D) costs, (54) but the public would finally get its end of the patent bargain--an adequate disclosure of X (which would hopefully spur more innovative activity during the patent term (55)) and possession of X when the patent expires. (56) Yet if a patent is unavailable, AcmePharma has little incentive to invest in the development of X. (57) AcmePharma and other firms may simply ignore X, thereby resulting in its ultimate loss to the public (which, in the case of a drug, could be enormous). (58) That the current novelty rules can actually deprive the public of socially beneficial inventions is cause for concern and merits attention.

The Article proceeds as follows. Part I explores the link between disclosure and possession in patent law. It explains that if X was inadequately disclosed in the original patent, the original patentee never possessed it; thus, the public never gained possession of X when the original patent expired. Part II draws attention to squandered patent claims, which are a direct result of inadequate disclosure in the original patent. It...

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