Patent prosecution refers to the interaction between inventors and a governmental patent office, such as the US Patent and Trademark Office (USPTO) or the European Patent Organization (EPO), to obtain a patent. Patent prosecution is analogous to a negotiation in which the inventors and the patent office agree on patentable subject matter or patentability. In the USA, patentable subject matter must be novel (not publicly disclosed), useful (functional) and non-obvious (unapparent to a skilled artisan).
Strategies behind patent procurement constantly change, in response to emerging technology, changes in patent rules or statutes and court decisions. For example, the emergence of biotechnology patent prosecution resulted in the landmark Supreme Court decision Diamond versus Chakrabarty, which held that a live, human-made microorganism is patentable subject matter as a ‘manufacture’ or ‘composition of matter’ Citation[1]. More recently, the controversial Tafas versus Doll litigation, regarding proposed rules limiting the number of claims and continuation applications set forth by the USPTO, remains unsettled, leaving patent prosecutors uncertain as to how to manage their patent portfolio Citation[2].
Recent US court decisions have altered strategies for patent procurement in biotechnology and pharmaceutical sciences. Notably, the Supreme Court decision in KSR International Co. versus Teleflex Inc. has significantly increased the burden of proof placed upon patent prosecutors in demonstrating the non-obviousness of chemical compounds and nucleic acid sequences Citation[3]. Recent Federal Circuit decisions have also affected the duty of disclosure, as evidenced by Larson versus AluminartCitation[4].
US Patent Statute 35 USC Section 103 relates to non-obvious subject matter or non-obviousness: “to reach a proper determination under 35 USC section 103, the examiner must step backward in time and into the shoes worn by the hypothetical ‘person of ordinary skill in the art’ when the invention was unknown and just before it was made. In view of all factual information, the examiner must then make a determination whether the claimed invention ‘as a whole’ would have been obvious at that time to that person” Citation[5]. To argue against an obviousness (apparent to a skilled artisan) rejection, the differences between the invention and the prior art, and the reasons as to why those differences are not apparent to the skilled artisan, should be ascertained. Examples of such differences include surprising superiority, disincentive in the art, no motivation in the art, teachings to modify reference teachings and no reasonable expectation of success.
Other patent systems, such as the EPO, use a ‘problem–solution’ analysis for determining an ‘inventive step’. The problem–solution analysis generally consists of three main stages:
First, determining the ‘closest prior art‘;
Second, establishing the ‘objective technical problem to be solved‘;
Third, considering whether or not the claimed invention, starting from the closest prior art and the objective technical problem, would have been obvious to a person skilled in the art.
The third step is subjective and constantly changes. The difference between obviousness in the USA and the inventive step in Europe might lead to different determinations of the inventive step of a patent application.
Previously, there had to be an incentive, motivation, teaching, suggestion or direction in the art to modify reference teachings to arrive at the invention in order for there to be obviousness. Pfizer versus Apotex, Inc. held that a suggestion, teaching or motivation to combine the relevant prior art teachings to achieve the claimed invention does not have to be found explicitly in the prior art references sought to be combined but, rather, “may be found in any number of sources, including common knowledge, the prior art as a whole or the nature of the problem itself” Citation[6].
In KSR International Co. versus Teleflex Inc., the Supreme Court rejected the teaching, suggestion and motivation test, as well as an ‘obvious-to-try’ analysis, “[w]hen there is a design need or market pressure to solve a problem and there are a finite number of identified, predictable solutions, a person of ordinary skill has good reason to pursue the known options within his or her technical grasp” Citation[7]. “Rigid preventative rules that deny fact finders recourse to common sense, however, are neither necessary under our case law nor consistent with it” Citation[8]. Thus, it is arguable that the USA is moving toward a problem–solution approach.
The KSR decision was extended to chemical compounds to render a purified stereoisomer of a known mixture obvious in Aventis Pharma Deutschland versus Lupin LtdCitation[9]; specifically, “isolation of interesting compounds is a mainstay of the chemist’s art” Citation[10]. However, the Court provided guidance that “a purified compound is not always prima facie obvious over the mixture; for example, it may not be known that the purified compound is present in or an active ingredient of the mixture, or the state of the art may be such that discovering how to perform the purification is an invention of patentable weight in itself” Citation[11]. In light of this case, an effective argument against an obviousness rejection should highlight disincentives regarding isolating, purifying or synthesizing the compound and emphasize the difficulties in the purification, isolation or synthesis that were overcome.
However, the KSR decision did not render a purified enantiomer obvious in Forest Laboratories versus Ivax PharmaceuticalsCitation[12]. In this instance, the claim was directed to a substantially pure enantiomer. The cited reference did not disclose a process of separating racemates and, furthermore, there was a previous failure in the art to separate the racemates. As indicated above, for patent disclosures relating to isolating compounds, arguments to overcome obviousness should highlight disincentives regarding isolating, purifying or synthesizing the compound, including difficulties in the purification, isolation or synthesis that were overcome.
The In re Omeprazole Patent Litigation also provides some guidance as to how to address obviousness rejections. In this litigation, expert testimony indicated that there was a “multitude of possible paths and dead-ends” in formulation attempts, the prior art taught away from the subcoated formulation and the prior art disclosure to omeprazole formulations did not disclose stability problems Citation[13]. Since recognition of problems and answers to problems in the art may lead to a finding of obviousness, a patent prosecutor should point to variables suggesting that results would be unpredictable.
The KSR decision has also extended to biotech patents. In re Kubin found that claims directed to DNA encoding a particular protein were invalid due to being obvious over the prior art, which taught the protein and ‘general cloning methods’. This is because the level of skill in the art had advanced sufficiently such that claims for a DNA sequence encoding a protein, when the encoded protein is already known, may now be considered obvious Citation[14]. Therefore, in drafting patent applications, a prosecutor should regularly review the state of the art and adapt his or her practice accordingly.
In summary, to overcome an obviousness rejection for disclosures relating to isolating compounds, a patent prosecutor should point toward disincentives regarding isolating, purifying or synthesizing the compound, emphasize difficulties in the purification, isolation or synthesis that were overcome and point to variables suggesting that results would be unpredictable. In addition, a prosecutor should regularly review and carefully consider changes in the state of the art when preparing the disclosure.
Recent case law has also impacted the duty of disclosure. This duty relates to informing the USPTO of all information known to any individual involved with patent prosecution (e.g., patent attorneys, patent agents, inventors, assignees, licensees or collaborators) to be material to patentability in an information disclosure statement (IDS; submission of relevant background art or information to the USPTO) Citation[15]. Such information may usually be found in references cited in counterpart foreign applications, search reports or closely related US patent applications. Related co-pending US patent applications (pending applications filed by the same applicant) should also be disclosed in an IDS.
However, disclosing co-pending patent applications in an IDS may be insufficient. Larson versus Aluminart affirmed that office actions from co-pending applications can be material to prosecution Citation[16]. Previous decisions, such as Dayco Products Inc. versus Total Containment, Inc. held “that a contrary decision of another examiner reviewing a substantially similar claim” is material, even if the co-pending application is in a separate patent family Citation[17]. Another decision relates to the failure of a patent applicant to disclose an office action and a notice of allowability in a continuation-in-part application of the patent in suit Citation[18]. The patent prosecutors in these cases were accused of inequitable conduct (breach of candor and good faith to the USPTO).
These decisions stress the importance of citing office actions in related patent applications in an IDS, even if the patent examiner is aware of the codependency of the applications and if the patent applications are in separate patent families. Therefore, a patent prosecutor should be vigilant in citing any paper (e.g., an office action, interview summary or reasons of allowability) in a related co-pending patent application that may be relevant during prosecution in an IDS. The citation of office actions in co-pending applications, even if the co-pending application is cited, indicates that patent examiners have, in part, shifted the burden of searching for material references to patent prosecutors.
Patent prosecutors continually shift their practice to adapt to new USPTO rules and regulations, as well as court decisions. The recent decisions affecting obviousness and disclosure have produced new challenges for patent prosecutors to overcome in the quest for and enforcement of a patent.
Financial & competing interests disclosure
The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.
No writing assistance was utilized in the production of this manuscript.
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Bibliography
- Diamond versus Chakrabarty , 447 US303 (1980).
- Tafas versus Doll , 559 F.3d 1345 (Federal Circuit 2009)
- KSR International Inc. versus Teleflex Inc ., 127 S.Ct. 1727 (2007).
- Larson Manufacturing Company versus Aluminart Products Ltd. , 559 F.3d 1317 (Federal Circuit 2009).
- Manual of Patent Examining Procedure (8th Edition) . Revision 4, section 2142 (2007).
- Pfizer v. Apotex Inc. , 480 F.3d 1458 (Federal Circuit 2007).
- KSR International Inc. versus Teleflex Inc. , 127 S.Ct. 1727, 1732–1742 (2007).
- KSR International Inc. versus Teleflex Inc. , 127 S.Ct. 1727, 1742–1743 (2007).
- Aventis Pharma Deutschland versus Lupin Ltd. , 499 F.3d 1293 (Federal Circuit 2007).
- Aventis Pharma Deutschland versus Lupin Ltd. , 499 F.3d 1293, 1302 (Federal Circuit 2007).
- Aventis Pharma Deutschland verus Lupin Ltd. , 499 F.3d 1293, 1303 (Federal Circuit 2007).
- Forest Laboratories versus Ivax Pharmaceuticals , 501 F.3d 1263 (Federal Circuit 2007).
- In re Omeprazole Patent Litigation , 490 F. Supp. 2d 381 (SDNY 1 June 2007).
- In re Kubin , 561 F.3d 1351 (Federal Circuit 2009).
- Manual of Patent Examining Procedure (8th Edition). Revision 4, section 2001 (2007).
- Larson Manufacturing Company versus Aluminart Products Ltd. , 559 F.3d 1317 (Federal Circuit 2009).
- Dayco Products Inc. versus Total Containment Inc ., 329 F.2d 1548, 1368 (Federal Circuit 2003).
- McKesson Information Solutions Inc. versus Bridge Medical Inc. , 487 F.3d 897 (Federal Circuit 2007).