March 25, 2024by Yanhong Hu

In Ex parte Perrot-Simonetta (Appeal 2023-000358), the Patent Trial and Appeal Board (“the Board”) reversed the Examiner’s obviousness rejection based on the principle of inherency.  

The claim at issue was directed to a steel part having a particular elemental composition and microstructure and exhibiting certain properties. Specifically, in addition to the specific mechanical strength, elastic limit, and breaking elongation, the claimed steel part had “a constriction at break greater than 30%.” 

The Examiner rejected the claim as obvious over Gao in view of Resiak and Han. The Examiner admitted that Gao was silent towards the constriction at break value but reasoned that since Gao described steel having overlapping composition, microstructure, and other mechanical properties, one skilled in the art would have found Gao’s steel necessarily had the recited constriction at break value. The Examiner additionally cited Resiak and Han, which described steel having the recited constriction at break value and admittedly “similar” but not identical compositions, to support her inherency/obviousness position.  

The Appellant argued that Resiak and Han provided evidence showing that Gao’s steel did not necessarily possess the characteristics of the claimed product, and thus rebutted, not supported, the Examiner’s allegedly prima facie case. In particular, the Appellant noted that Resiak described a steel with the recited mechanical strength and constriction at break value but not the recited breaking elongation value. The Appellant further noted the different processing parameters for steel described in Gao, Resiak, and Han and argued that the secondary references could not provide any information on the constriction at break value of Gao.  

The Board agreed with the Appellant and held that the combined prior art teaching did not support the Examiner’s finding that the recited properties were necessarily present in Gao’s steel. Judge Owens further noted in his concurring opinion that the Examiner had exercised impermissible hindsight.  

Takeaway:  A prima facie case of either anticipation or obviousness is established when the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes. However, as shown in Perrot-Simonetta, mere overlap in composition and structure may not be sufficient to establish that the claimed and prior art products are identical or substantially identical in structure or composition.  

Judges: Terry J. Owens, Catherine Q. Timm, and Lilan Ren 


March 3, 2023by Yanhong Hu

The USPTO is currently operating an interim process for Director review in response to the Supreme Court’s decision in United States v. Arthrex, Inc., 141 S. Ct. 1970 (2021), which held that decisions rendered by the Administrative Law Judges of the Patent Trial and Appeal Board (PTAB; “Board”) regarding patent validity were not the final decisions of the agency without the ability for the Director of the USPTO to intervene. Under the interim Director review process, any party to a PTAB proceeding (e.g., inter partes review (IPR) and post-grant review (PGR) proceedings) may request review by the Director using a process similar to the current PTAB rehearing procedure.  

Director Vidal has actively used the Director review process since she took office last April. In one of her recent decisions (Nested Bean, Inc. v. Big Beings Pty Ltd., IPR2020-01234, Paper 42 (February 24, 2023)), the Director decided on the issue of assessing patentability of multiple dependent claims, which was deemed to be an issue of first impression.  

Nested Bean filed an IPR petition challenging claims 1-18 of a patent owned by Big Beings. Claims 1 and 2 were independent claims; claims 3-16 were multiple dependent claims depending directly or indirectly from either claim 1 or 2; and claims 17 and 18 were single directly or indirectly dependent claims of claim 1.  

The Board found that claims 1, 17, and 18 were patentable but claim 2 was unpatentable. With respect to the multiple dependent claims 3-16, the Board considered them to be anticipated or rendered obvious by the prior art if either the version depending from claim 1 or the version depending from claim 2 was described by the prior art. Because the Board found that the version depending from claim 2 was unpatentable, without separately considering the patentability of the claims as dependent from claim 1, the Board concluded that claims 3-16 were also unpatentable.  

Big Beings filed a request for Director review and argued that the Board should have found claims 3-16, as depending from claim 1, were patentable under pre-AIA 35 U.S.C. § 112, fifth paragraph, which was the statute governing the multiple dependent claims of the patent at issue. Director Vidal granted the request and noted that the determinations and rationale in her decision applied equally to the corresponding post-AIA version of the statute, i.e., 35 U.S.C. § 112(e). 

After reviewing the language of the relevant statutes and regulations governing multiple dependent claims, Director Vidal found that the plain language of § 112, fifth paragraph, which states “[a] multiple dependent claim shall be construed to incorporate by reference all the limitations of the particular claim in relation to which it is being considered,” clearly communicated that “a multiple dependent claim is the equivalent of several single dependent claims.” In addition to the statutory language, the Director further examined other interpretive sources, including Federal Circuit case law, the statute’s legislative history, and the current USPTO guidance and practice, and found that all these sources also supported the conclusion that a multiple dependent claim must be considered as a plurality of single dependent claims. Therefore, the Director agreed with Big Beings and held that “multiple dependent claims must be treated as multiple claims, each comprising the dependent claim and one of the claims to which it refers, and the validity (and/or unpatentability) of each of the multiple claims must be considered separately.”  

Accordingly, the Director determined that the Board “erred in its analysis of multiple dependent claims 3-16 by failing to separately consider that claims 3-16 incorporate by reference the limitations of claim 1” and granted rehearing and modified the Board’s Final Written Decision.  

Takeaway:  By citing cases addressing alternatively recited limitations in the body of a claim as supporting its position, Nested Bean, the Petitioner, appeared to urge the Director to treat claim dependency of a multiple dependent claim in the same manner as treating alternatively recited claim features. The Director rejected this treatment. Noting that the statute is clear in specifying that a multiple dependent claim must be interpreted as several single dependent claims, the Director has clarified that the patentability of a multiple dependent claim must be separately evaluated as to each of its alternatively referenced claims.


December 1, 2022by Yanhong Hu

In Ex parte Langenfeld (Appeal 2021-004075), the Examiner rejected the claims as obvious over a combination of prior art references and based on the theory of design choice. The Patent Trial and Appeal Board (“Board”) reversed.  

The invention at issue was directed to a method of producing rolled food products that included a step of cutting a dough sheet to form a roll sheet having a continuous pattern comprised of “an asymmetrical repeat unit.” 

Wolf, the primary reference found by the Examiner, described a method of producing croissants. As admitted by the Examiner, Wolf did not disclose a cutting pattern that would produce an asymmetrical repeat unit. The Examiner then turned to Mel, which described making homemade crescent rolls. Mel disclosed cutting a circular dough into triangles and described that it was all right if the “triangles aren’t all perfect” because “[that] is something special about home cooking – it is not all perfect and rigid.” The Examiner thus concluded that “it would have been obvious to form the triangles and subsequently the rolls of Wolf as slightly asymmetrical in order to create a ‘homemade’ appearance that is special and pleasing to consumers.” The Examiner further contended that the claimed asymmetrical repeating unit shape was merely an obvious matter of design choice, alleging that the shape and symmetry of the rolls would have been obvious to adjust in the absence of a demonstration of criticality. 

However, the Board found that, at best, Mel only suggested random variations, not “asymmetrical repeat units” as required by Appellant’s method. Thus, the Board agreed with Appellant that not only the resulting arrangement of Wolf as modified by Mel failed to meet the claim limitation, but Mel was “directly contrary to the Examiner’s conclusion that all the produced rolls would be the same and have the same asymmetry” in that Mel equated the homemade look to imperfection.  

With respect to the Examiner’s allegation of obvious design choice, the Board noted that Appellant provided evidence showing that the asymmetrical repeating unit was significant to the invention (specifically, it was possible to retain a symmetrical outer appearance despite that each of crescent rolls had a different amount of dough at each end) and was more than one of the numerous configurations a skilled artisan would have found obvious for the purpose of forming rolled dough products. Because the prior art had no suggestion for changing the shape to any asymmetrical repeating unit shape, the Board found the evidence provided by Appellant was sufficient to prove non-obviousness. In addition, the Examiner did not adequately rebut Appellant’s evidence of significance. Therefore, the Board held that Appellant need not show the criticality of the change in shape for unexpected results and reversed the Examiner’s obviousness rejection.  

Takeaway: When a claim feature cannot be found in prior art, examiners may apply the theory of “design choice” and often also request applicants to provide evidence of criticality to overcome an obviousness rejection based on design choice. Langenfeld, again, clarifies that evidence of criticality is not necessary under such circumstances if applicants provide unrebutted evidence of significance. Examples of evidence of significance include a different function associated with the claim feature, a stated problem solved by the claim feature, and improvements, advantages, and benefits of the claim feature (see also one of our previous posts here). Such evidence can be found in applicant’s specification and/or prior art or can be provided in the form of a declaration during examination.  

JudgesC. Q. Timm, G. C. Best, and N. W. Wilson 


August 18, 2022by Yanhong Hu

Examiners often make § 112(b) indefiniteness rejections when claims include relative terms. The Patent Trial and Appeal Board (“Board”) in Ex parte Rehder (Appeal 2021-003607) considered such a rejection.

The illustrative claim in Rehder was directed to a solar cell structure of a carrier, a solar cell, and an adhesive layer including an adhesive material and conductive carbon nanostructures that electrically coupled the carrier to the solar cell. The claim required that “the conductive carbon nanostructures within the adhesive layer do not generally contact one another.”

The Examiner found that the specification disclosed a volume percentage of about 0.1% to about 1.0% for the carbon nanostructures, which resulted in the nanostructures generally not contacting one another. However, noting that limitations from the specification were not imported into the claims, the Examiner alleged that the use of the relative term “generally” rendered the claim indefinite.

Appellant contended that the ordinary meaning of the term “generally” should apply. According to appellant, when “generally” is interpreted in light of the specification, it is clear that “exceptions” to the requirement of non-contact are permitted, especially because “it would be difficult, if not impossible, to guarantee that each and every carbon nanostructure situated in the claimed adhesive layer does not contact an adjacent nanostructure.”

The Board noted that, for determining the question of indefiniteness, exact precision is not required; instead, the test could be formulated as whether the claims “set out and circumscribe a particular area with a reasonable degree of precision and particularity.” Regarding the reasonable standard, the Board emphasized that one must consider the language in the context of the circumstances.

The Board particularly noted that the use of relative terms did not automatically render a patent claim indefinite. The Board reviewed precedent approving the use of relative terms such as “about,” “substantially,” “approximately,” and “generally” and found that these relative terms were used to provide some “wiggle room” around a readily ascertainable limit such as a strict numerical limit. Applied to the instant case, the Board concluded that the term “generally” was used to provide some “wiggle room” with respect to the requirement that carbon nanostructures not contact one another. The Board further noticed that the specification taught that due to the low concentration of the carbon nanostructures dispersed in the adhesive material, the nanostructures “do not generally make contact with one another.” The Board noted that the Examiner did not challenge the reasonableness of this disclosure and found that its reasonableness appeared on its face to be sound.

Therefore, the Board concluded that the phrase, “do not generally contact one another,” envisioned some amount of deviation from exactly no contact between the carbon nanostructures in the adhesive layer and was clear and definite.

Takeaway:  Relative terms, including terms of degree, in claim language are not necessarily indefinite. The key is whether the language provides enough certainty to one of ordinary skill in the art to understand what is claimed in light of the specification. For example, it is always advisable to include in the specification some examples or teaching that can be used to measure a degree if terms of degree are used. The Board in Rehder held that the term “generally” was definite because a skilled artisan would be able to ascertain the scope of the claim in light of the specification.

JudgesJ. C. Housel, N. W. Wilson, and B. D. Range


July 8, 2022by Yanhong Hu

Ex parte Deporter (Appeal 2021-003598) is a recent decision of the Patent Trial and Appeal Board (“Board”) where the Board considered whether a prior art reference taught away from Appellant’s claimed invention.

The claim at issue was directed to a composite structure of at least one spunbonded, nonwoven, polymeric layer and at least one meltblown, nonwoven, polymeric layer. The Examiner found that the primary reference, Moore, disclosed each element of the claim except that Moore did not teach “at least one of the spunbonded layers comprises inorganic particulate filler in an amount from about 12% by weight to about 16% by weight of the spunbonded layer.” The Examiner found that the secondary reference, McAmish, taught nonwoven fabrics of spunbonded polymeric fibers which contained fillers such as calcium carbonate particles in an amount of about 10-15 wt% and the associated advantages. The Examiner thus determined it would have been obvious to use from 10-15 wt% of filler in one of Moore’s spunbonded layers as motivated by the advantages described in McAmish.

Appellant argued that there would be no motivation to modify Moore’s structure using McAmish’s amount of filler because Moore taught away from using so much filler. In particular, as noted by Appellant, Moore disclosed that “[f]illers, plasticizers, and other additives, when used at levels above 3% by weight, and more certainly above 5% by weight of the aliphatic polyester, can have a significant negative effect on physical properties such as tensile strength of the nonwoven web. Above 10% by weight of the aliphatic polyester resin, these optional additives can have a dramatic negative effect on physical properties.”

However, Moore also disclosed that “total optional additives including any particulate phase other than antishrinkage additive, preferably are present at no more than 10% by weight, preferably no more than 5% by weight and, most preferably no more than 3% by weight.” Based on such disclosure, the Examiner contended that Moore “does not … expressly teach away from the combination [of Moore and McAmish]” because “Moore acknowledges fillers as high as 10%.”

The Board acknowledged that “[in] some circumstances, the use of the word ‘preferably’ in this context might militate against a finding of teaching away.” However, the Board found that Moore’s specific statement that using above 10% by weight “can have a dramatic negative effect on physical properties” was “direct and specific enough” to outweigh the possibility that “a person of skill in the art might see the word ‘preferably’ and consider using more than 10% of filler.”

Therefore, the Board agreed with Appellant that Moore taught away from using 12-16% by weight of an inorganic particulate filler in at least one of the spunbonded layers and reversed the Examiner’s obviousness rejection.

Takeaway:  Teaching away from an applicant’s claimed invention is a strong indication that it would not have been obvious. Teaching away can be found in a situation where a reference criticizes, discredits, or otherwise discourages the route the applicant takes. However, it is also well-settled that the indication that a certain embodiment is a preferred embodiment is not a teaching away. Deporter is a case where the two situations coexist. It illustrates that “teaching away” is still an effective rebuttal argument for patentees, especially when a reference specifically and directly discourages the alleged modification.

Judges:  B. A. Franklin, G. C. Best, and N. W. Wilson


May 20, 2022by Yanhong Hu

In Ex parte Stone (Appeal 2021-004177), the Patent Trial and Appeal Board (“Board”) reversed the Examiner’s obviousness rejection citing Lucas, Kaersgaard, and Wu because the Examiner did not meet his initial burden of presenting a prima facie case of obviousness.

Appellant’s claimed invention in Stone was directed to a method of “selectively removing a proteinaceous impurity from a sample comprising at least an immunoglobulin and the proteinaceous impurity.” It included steps of “adjusting the solution pH of the sample, such that the pH is within 2.0 pH units of the isoelectric point of the proteinaceous impurity to be selectively removed,” then “contacting the sample with activated carbon, [which] selectively binds the proteinaceous impurity,” and “removing the activated carbon from the sample.”

Lucas described the presence of contaminants in monoclonal antibodies and also taught that the contaminants should be removed to produce monoclonal antibodies of the highest purity. However, Lucas did not disclose how to remove the contaminants. The Examiner acknowledged this deficiency. The Examiner found that Kaersgaard described removing PEG from immunoglobulins using activated carbon and Wu described removing proteinaceous material from corn syrup using activated carbon. The Examiner also found that Wu disclosed that the maximum adsorption of the proteinaceous material by the activated carbon occurred at the protein’s isoelectric point. The Examiner thus determined that it would have been obvious to a skilled artisan “to remove the impurities of Lucas” by Wu’s method “motivated by the desire for highest purity, described by Lucas;” and reasoned that because Kaersgaard “teach[es] using very similar methods for purifying immunoglobulins, and explicitly discuss[es] using the methods to remove other impurities, an artisan in this field would attempt this process with a reasonable expectation of success.”

Appellant argued that the combination of cited references did not suggest the claimed method or provide the motivation to combine Wu with Lucas and Kaersgaard. Specifically, Appellant argued that none of the cited references described the selective removal of a protein impurity from other proteins, noting that Kaersgaard disclosed removing PEG rather than a protein impurity from immunoglobulins and Wu disclosed removing proteins from corn syrup, but did not teach selectively removing a proteinaceous impurity from other proteins based on the isoelectric point of the impurity as required by Appellant’s claimed method.

The Board agreed with the Appellant. The Board noted that Lucas identified the need to remove protein contaminants but did not teach how to do so. The Board also noted that neither Kaersgaard nor Wu described selective removal of a protein. In particular, Wu described removal of all protein contaminants, despite teaching that the maximum adsorption of a protein could be achieved using the pH of the protein’s isoelectric point. The Board noted that the Examiner did not provide adequate reasoning to modify Wu to selectively remove impurities. Specifically, regarding the Examiner’s contention that Appellant’s arguments “assume that a person of skill in the art cannot make the leap from the explicit experiments and motivations of the reference to other, closely related applications and goals,” the Board pointed out that the Examiner did not provide a reason for making the “leap” from adsorbing all proteins from a solution to adsorbing only certain proteins based on their isoelectric point.

The Board emphasized that it was the Examiner who had the initial burden of presenting a prima facie case of obviousness and that ordinary creativity and/or common sense “cannot be used as a wholesale substitute for reasoned analysis and evidentiary support, especially when dealing with a limitation missing from the prior art references specified.” The Board cautioned that although the Supreme Court emphasized “an expansive and flexible approach” to the obviousness approach, it also reaffirmed the importance of determining “whether there was an apparent reason to combine the known elements in the fashion claimed by the patent at issue.”

Because the Examiner failed to provide sufficient reason to selectively remove proteinaceous impurity as claimed, the Board reversed the Examiner’s obviousness rejection.

Takeaway:  Obviousness can be established by combining or modifying the teachings of prior art references to produce a claimed invention where there is some teaching, suggestion, or motivation to do so and there is a reasonable expectation of success. The Examiner in Stone did not establish obviousness because, although Wu disclosed adsorption of a protein was related to the pH of the protein’s isoelectric point, the Examiner failed to present sufficient reasoning to modify Wu’s teachings to achieve the claimed selective removal of a proteinaceous impurity. As the Board pointed out, an examiner’s assertion of ordinary creativity and/or common sense cannot substitute for reasoned analysis and evidentiary support.

Judges:  E. B. Grimes, R. M. Lebovitz, and G. C. Best


April 15, 2022by Yanhong Hu

Functional equivalence is a rationale that examiners often rely on in support of an obviousness rejection. However, as discussed in one of our previous blogs, examiners may misapply the rationale by ignoring the different function or purpose of an allegedly equivalent component disclosed in prior art. A recent decision of the Patent Trial and Appeal Board (“Board”) – Ex parte Takasu (Appeal 2021-001290) – is another illustrative case.

Appellant’s claimed invention in Takasu was a substrate of a single crystal of formula RAMO4, where, among other things, R could be Sc, A could be Al, and M could be Mg. The claimed RAMO4 substrate had an epitaxially-grown surface and a satin-finish surface, each having specific surface roughness.

Yoshii, the primary reference relied on by the Examiner, provided a sapphire substrate for epitaxial growth that could be easily polished. The Examiner found that Yoshii as evidenced by Hansen disclosed a sapphire single crystal substrate that allegedly had the claimed roughness on its front and back sides. The Examiner admitted that the sapphire substrate disclosed in Yoshii was not a RAMO4 substrate. However, the Examiner found a secondary reference, Yoshida, which disclosed ScAlMgO4 as one of the material options for a single crystalline substrate as a functional equivalent to sapphire for epitaxial growth. The Examiner thus concluded Appellant’s claimed RAMO4 substrate would have been obvious over Yoshii in view of Yoshida as evidence by Hansen.

Appellant argued that a sapphire substrate and a RAMO4 substrate were not equivalent to each other in terms of surface polishing properties.

The Board agreed with Appellant and emphasized that, as stated by the Examiner herself, Yoshida merely disclosed ScAlMgO4 as “a functional equivalent to sapphire for epitaxial growth, but … not for surface polishing properties.”

Because a sapphire substrate is not functionally equivalent to a RAMO4 substrate in terms of surface polishing properties, the Board found that the Examiner’s reliance upon Yoshida was misplaced and reversed the obviousness rejection.

Takeaway:  As cautioned in MPEP § 2144.06 II, the equivalency of a proper substituting equivalent must be recognized in the prior art for the same purpose and cannot be based on applicant’s disclosure or the mere fact that the components at issue are functional or mechanical equivalents. Thus, arguments rebutting an examiner’s obviousness rejection relying on functional equivalence may be successfully advanced by carefully analyzing the function and purpose of substituted and substituting components disclosed in prior art.

Judges:  J. T. Smith, B. A. Franklin, and J. R. Snay


March 11, 2022by Yanhong Hu

Applicants can traverse rejections by submitting evidence in the form of a declaration under 37 CFR 1.132. While factual evidence, such as additional experimental data, is preferable, opinion testimony, which is often brushed off by examiners, is entitled to consideration as long as the opinion is not on the ultimate legal conclusion. A recent decision of the Patent Trial and Appeal Board (“Board”) – Ex parte Zhu (Appeal 2021-001375) – illustrates a situation where an expert’s opinion testimony provided evidence that successfully traversed the Examiner’s obviousness rejection.

Appellant’s claimed invention in Zhu was directed to an electrochemical test sensor containing a base, a lid, multiple electrodes, and a dried reagent. The dispositive issue before the Board was whether the evidence of record supported the Examiner’s finding that the primary reference (Bateson) described or suggested an electrochemical test sensor having a dried reagent that “has a uniformity in which the ratio of the thinnest point to the thickest point is greater than about 0.2” as claimed.

The Examiner admitted that Bateson did not explicitly disclose the feature but provided a hypothetical calculation based on Bateson’s disclosure, including the drawings, and obtained a ratio of 0.64 between the thinnest and thickest points.

Appellant responded with declaratory evidence from Mr. Brown (an employee of the assignee’s subsidiary company) explaining why the Examiner’s hypothetical calculation was erroneous. Mr. Brown stated that when a dry reagent was obtained from a wet reagent, “[t]he exact percentage of the reduction in the thickness would depend on the drying conditions and the crystalline or molecular structure of the dissolved solid materials in the wet reagent.” Mr. Brown further stated that “details like the contour of the dried reagent” must be considered when the ratio was calculated because the surface of the dried reagent was not smooth, citing a figure in Appellant’s application as a proof and noting that a skilled artisan would expect the dried reagent in Bateson to exhibit the “coffee ring” effect upon drying, which represented a non-uniform reagent surface.

The Examiner gave little or no weight to Mr. Brown’s statements. While noting that Bateson did not disclose the “coffee ring” effect or details pertaining to the surface contour of the wet or dried reagent, the Examiner argued that “it would be improper to read into the disclosure of Bateson to give the surface of the reagent any particular contour without some teaching, suggestion and/or evidence to do so.”

The Board, however, found that Brown’s testimony was valid evidence showing that a skilled artisan would have expected a calculation of the ratio to require details such as the contour of the surface of the reagent. Because, as acknowledged by the Examiner, Bateson did not disclose any noteworthy details regarding the surface contour of the reagent, the Board found that the record before it supported Appellant’s position that the Examiner failed to make a sufficient showing that Bateson disclosed or suggested the recited ratio.

Takeaway:  It is known to patent practitioners that arguments of counsel are not evidence and must be supported by an appropriate affidavit or declaration from an expert. The expert can be an outside expert or someone from inside the company as in Zhu as long as they have appropriate expertise. While an opinion affidavit or declaration which states only conclusions may have little probative value, weight and deference should be given to factually supported statements and, particularly, to the underlying factual basis, as illustrated by Zhu.

Judges:  M. N. Ankenbrand, B. D. Range, and L. Ren


February 11, 2022by Yanhong Hu

A typical Markush group is structured as “selected from the group consisting of A, B, and C.” The language is closed in nature due to the closed transitional phrase “consisting of.” However, it is not uncommon for an open-ended claim to recite a Markush group in patents or patent applications related to chemical arts. An issue that often arises , therefore, is whether unrecited members of the “closed” Markush group are allowed in open-ended claims. In Ex parte Kapitan (Appeal 2021-001272), the Patent Trial and Appeal Board (“Board”) addressed such an issue.

Appellant’s claimed invention in Kapitan was directed to a process for making a methylfluoroacrylate “comprising” steps A-D, wherein “the solvent in at least steps C and D … is an alkane selected from a group consisting of pentane and hexane.”

The Examiner rejected the claimed process as obvious over a combination of several prior art references. The Examiner admitted that the primary reference did not disclose using pentane or hexane as the solvent in making methylfluoroacrylate; and relied on a secondary reference, Sedlak ‘967, for the admitted deficiency. In particular, the Examiner found Sedlak ‘967 used inert solvent, including petroleum ether, which, according to the Examiner, “consists of pentane and hexane hydrocarbons.” However, as noted by the Board, the Examiner did not provide evidence establishing that petroleum ether was either pentane or hexane.

Appellant, on the other hand, provided several prior art references during prosecution showing that petroleum ether was not a single composition but a mixture of aliphatic hydrocarbons, such as a mixture of C5 to C13 paraffins that might contain a small amount of aromatic hydrocarbons.

The Board thus agreed with Appellant that petroleum ether had numerous variations of petroleum ether components that were not limited to pentane or hexane. The Board noted that by using the open-ended transitional phrase “comprising,” the claimed process allowed for additional steps. However, the Board further noted “that additional steps may be allowed does not mean that the solvent for use in the reaction step C as modified by the wherein clause, i.e., the alkane solvent [] being ‘selected from a group consisting of pentane and hexane,’ can be something other than pentane or hexane.” Citing Amgen, Inc. v. Amneal Pharms. LLC, 945 F.3d 1368, 1377–78 (Fed. Cir. 2020), which discussed in detail Multilayer Stretch Cling Film Holdings, Inc. v. Berry Plastics Corp., 831 F.3d 1350 (Fed. Cir. 2016), the Board concluded that, just as was the case in Multilayer, the suitable solvent required to be used in step C in Appellant’s claimed process was restricted to the listed solvents by the use of the closed Markush transition phrase “selected from the group consisting of.”

Because Sedlak ‘967’s teaching of using “petroleum ether” in its reaction scheme as an inert solvent did not indicate that pentane or hexane alone was a suitable inert solvent, the Examiner’s application of the prior art references was not sustainable.

TakeawayKapitan, like Multilayer, illustrates that without other language altering the meaning of a Markush clause, other unrecited members or mixtures of the recited members are not allowed even in an open-ended claim. Amgen illustrates a different situation. Specifically, the Amgen Court held that additional unrecited members of a Markush group and mixtures of the recited members were allowed if the Markush clause included qualifying language such as “at least one” as in “at least one selected from the group consisting of A, B, and C” and was preceded by an open-ended transitional phrase such as “comprising.” Indeed, the result would have been different if Appellant in Kapitan had recited “the solvent in at least steps C and D … comprises an alkane selected from the group consisting of pentane and hexane.”

Judges: D. E. Adams, T. Chang, and R. H. Townsend


December 29, 2021by Yanhong Hu

In Ex parte Price (Appeal 2021-003888), the Patent Trial and Appeal Board (“Board”) reversed the Examiner’s obviousness rejection because of Appellant’s successful showing of unexpected results.

Claim 1 was illustrative and read:

A ballistic material, comprising:

a first woven para-aramid ballistic fabric having a fiber denier in a range of 50 d to 5000 d; and

a hydroentangled nonwoven fiber component consisting essentially of ballistic grade para aramid fibers having a denier in a range of about 0.5 d to about 2.5 d and a density of about 10 gsm to about 200 gsm; wherein

the hydroentangled nonwoven component is needlepunched with the woven ballistic fabric to form a consolidated material.

The Examiner rejected claim 1 as obvious over Price in view of Van der Loo. Price taught a similar consolidated material but was silent on its non-woven component being “hydroentangled.” Instead, Price’s nonwoven was manufactured, for example, by dry laid carding and mechanical needling. The Examiner thus turned to Van der Loo and found that Van der Loo provided suggestion of using hydroentangling instead of needling to form a nonwoven.

The Board did not find that the Examiner’s combination of Price and Van der Loo was unreasonable. However, the Board found that the Examiner failed to give proper weight to Appellant’s evidence of unexpected results presented by Declarant Brahms.

The Board noted that Appellant first provided evidence regarding the expectation of the ordinary artisan. In particular, according to Appellant, “[t]he expectation in the art is that an identical stack of woven para-aramid layers reinforced with the same weight of nonwoven para-aramid fibers of the same denier would yield the same ballistic performance.” Appellant supported this statement with evidence showing linearity of the correlation between weight and ballistic performance measured as V-50.

Appellant then provided declaratory evidence that their results were significantly different from those of the closest prior art. In particular, after comparing the V-50 performance of shoot packs formed of ballistic materials made with identical materials and by identical processes except for the use of a non-woven that was hydroentangled versus needled, Brahms declared the observed difference was not merely random as verified by statistical analysis.

Finally, Brahms declared that the result was unexpected. In particular, according to Brahms, “[w]hen we first substituted spunlace material, we had hoped for some processing advantages and some reduction in weight for the final ballistic product. We did not expect an improvement in ballistic properties.” Brahms further declared that “[s]pecifically, an amount of fiber material, incorporated as spunlace, produced unexpected advantages in terms of the ballistic performance as compared to the same amount of fiber material incorporated from a needled batting. We now believe that the improvement in ballistic performance is due to the availability of the fibers of the spunlace material.”

The Board dismissed the Examiner’s determination that Appellant’s results were expected, because the Examiner improperly discounted Brahms’s specific statements that the difference was unexpected in that it was surprising that lower weight products would achieve V-50 ballistic performance improvements above the normal linear correlation seen in other known products.

Takeaway:  Any differences between a claimed invention and prior art may be expected to result in some differences in properties. What matters is whether the differences in properties are of a magnitude that really would have been unexpected. Ex parte Price illustrates a scenario where applicant can prove unexpected results by showing results that are “greater than” what is normally expected.

Judges:  A. L. Hanlon, C. Q. Timm, and N. W. Wilson