October 8, 2021by Yanhong Hu

“A picture is worth a thousand words.” This is also true, and sometimes may be even more so, in patent applications. However, one should be careful about what a figure in a patent application does and does not say. A recent decision of the Patent Trial and Appeal Board (“Board”) in Ex parte Hogard (Appeal 2020-006394) illustrates this point.

Appellant in Hogard claimed a method of controlling a fluid level in a venous drip chamber of a dialysis system having a blood pump and an air pump. The claimed method required operation of the blood pump in first and second modes that resulted in the fluid (i.e., either blood or saline) moving both forwards and backwards through the tubing set.

The Examiner rejected the claimed method as obvious over Heyes in view of Folden. The Examiner admitted that Heyes did not disclose the claimed priming sequence. However, the Examiner cited Folden, which taught bi-directional flow, as making up for the deficiency of Heyes.

Relying on Heyes’ Figure 7 (viewable here), Appellant argued that Heyes’ fluid path was meant to be unidirectional only and the Examiner’s proposed modification would have rendered Heyes’ device inoperable. In particular, noting that Figure 7 illustrated aperture 30 of bubble trap 34 being above level sensor 44, Appellant argued that if saline flowed in the reverse direction through the bubble trap, due to the position of inlet lip 36 (which was the entry point to aperture 30), the saline level would have to be higher than level sensor 44. Appellant argued that having no control of the fluid level within the chamber would have caused the hydrophilic membrane covering the vent in bubble trap 34 to become wetted and non-useful. Therefore, Appellant argued that the Examiner’s proposed modification of Heyes by Folden to have priming fluid flow in the reverse direction during priming would have caused Heyes’ bubble trap 34 inoperable due to a wetted hydrophilic membrane.

The Examiner raised two counter arguments in his answer. First, the Examiner argued Appellant’s arguments regarding the location of aperture 30 were moot because the drawings of Heyes were not to scale. Second, the Examiner argued even if aperture 30 was above level sensor 44, it would have been obvious to configure Heyes’ bubble trap 34 so that the level sensor prevented saline from contacting the hydrophilic membrane.

Appellant agreed Heyes did not indicate that its figures were drawn to scale. However, citing Vas-Cath Inc. v. Mahurkar, 935 F.2d 1555, 1565 (Fed. Cir 1991), Appellant argued that the drawings could be used to establish “relative sizes and relationship between the various components which are clearly depicted in those drawings.” Specifically, Appellant argued that the relative positions of aperture 30, level sensor 44, and the hydrophilic membrane of bubble trap 34 depicted in Heyes’ Figure 7 made it clear that Heyes’ bubble trap 34 was designed only for unidirectional flow. In response to the Examiner’s second counter argument, Appellant argued modification of Heyes’ bubble trap 34 to operate bi-directionally amounted to a significant change in the function of Heyes’ device.

The Board was persuaded by Appellant’s arguments. The Board agreed with Appellant’s interpretation of Heyes’ Figure 7 and pointed out that “[p]atent drawings may not be disregarded for items that they clearly show.” The Board also sided with Appellant’s position regarding the change in function and emphasized that “[i]f the proposed modification or combination of the prior art would change the principle of operation of the prior art invention being modified, then the teachings of the references are not sufficient to render the claims prima facie obvious.” The Board further noted the well-settled law that “which is within the capabilities of one skilled in the art is not synonymous with obviousness” and that “[t]he mere fact that the prior art may be modified in the manner suggested by the Examiner does not make the modification obvious unless the prior art suggested the desirability of the modification.”

Because the Board concluded that there was no suggestion in the applied art to modify Heyes’ system for unidirectional flow by Folden’s method of priming a dialysis system using bi-directional flow, the Board reversed the Examiner’s obviousness rejection.

Takeaway:  If a reference does not disclose that the drawings therein are to scale and is silent as to dimensions, arguments based on measurements of features in the drawings are of little value. However, an examiner can rely on features of drawings that are not explicitly described in a reference, if the meaning or intent of such features would be apparent to one of ordinary skill in the art viewing the reference. Ex parte Hogard illustrates a situation where an applicant was similarly able to rely on the manner in which a skilled artisan would have understood the drawings to rebut a rejection.

JudgesB. A. Franklin, J. B. Roberstson, and C. C. Kennedy


September 3, 2021by Yanhong Hu

In Ex parte Sharma (Appeal 2020-004468), the Patent Trial and Appeal Board (“Board”) considered the Examiner’s obviousness rejection of Appellant’s claimed method of treating once-through steam generator (OTSG) blowdown water for reuse based on “equivalents” allegedly described in a secondary reference.

Claim 1 was representative and the claimed method included, among other steps, a step of “settling precipitants out of said OTSG blowdown water for at least 12 hours to produce an acid clarified blowdown water having more than 50% of the acid insoluble organics removed.”

The Examiner found that Bansal, the primary reference, described a method of treating OTSG blowdown water by separating the solids from the liquid via a centrifuge and admitted that Bansal did not teach that solids and precipitants were settled out for at least 12 hours as claimed. However, the Examiner alleged that Cote, the secondary reference, described various equivalent separation devices, including settling ponds and centrifuges. The Examiner thus alleged claim 1 would have been obvious over Bansal in view of Cote.

Appellant countered that Cote did not teach that pond settling was “equivalent” to Bansal’s high speed centrifuging and particularly pointed out that the high pressure centrifuges described in Bansal exerted 3000-3500 times the force exerted in a settling pond.

The Board noted Cote disclosed that solids generated during wastewater processing of a phosphogypsum pond processes “may be removed by one or more suitable solids separation devices such as a clarifier, settling pond, lamella clarifier, upflow sludge blanket clarifier, disk filter, centrifuge, vacuum filter, dissolved air floatation device or the like.” According to the Board, Cote’s statement that “one or more” of these separation devices could be used only indicated that settling and centrifuges were both solids separation devices, but “not that they are equivalent.” Instead, as the Board continued, “the suggestion is that settling and centrifugation are complementary approaches that may be used in combination.”

Further, as the Board noted, Bansal disclosed that the smaller size and relative softness of the solids described therein limited the ability to separate liquid and solid phases by conventional centrifuging or hydrocycles and that the oily organics further limited ability to utilize filtering since the particles tended to stick together agglomerating and clogging filter media. Therefore, the Board found Bansal indicated that settling would not work in its process.

Citing In re Ruff, the Board emphasized “[t]hat two things are actually equivalents, in the sense that they will both perform the same function, is not enough to bring into play the rule that when one of them is in the prior art the use of the other is obvious and cannot give rise to patentable invention” and “[t]o rely on equivalence as a rationale supporting an obviousness rejection, the equivalency must be recognized in the prior art, and cannot be based on an applicant’s disclosure or the mere fact that the components at issue are functional or mechanical equivalents.”

Because the Examiner erred by finding that the prior art recognized settling and centrifugation as equivalents, the Board concluded one of ordinary skill in the art would not be expected to substitute settling for Bansal’s high pressure centrifugation and reversed the Examiner’s obviousness rejection.

Takeaway: As noted in Mat Barnet’s prior blog on interchangeable equivalents, for a component missing from a primary reference, U.S. patent examiners usually cite a secondary reference disclosing the missing component and resort to the rationale of simple substitution by alleging that the substituting component disclosed in the secondary reference is equivalent to one of the components in the primary reference (i.e., the substituted component). One justification for the substitution the examiners often rely on is that the secondary reference describes various components, including both the substituting and substituted components, by using terms such as “include,” “one or more,” and “at least one.” As illustrated by Sharma, such description alone cannot justify the substitution rationale. Instead, the equivalency must be described in the prior art references so that it is recognized by one of ordinary skill in the art in light of the prior art description.

Judges: G. C. Best, D. M. Praiss, D. L. Dennett


July 30, 2021by Yanhong Hu1

What does “up to at least 150 volts” mean? Does it mean 150 volts is a maximum voltage due to the use of the words “up to” or a minimum voltage due to the use of the words “at least”? This was the problem the Patent Trial and Appeal Board (“Board”) in Ex parte Bagehorn (Appeal 2020-004760) had to solve.

Claim 1 was the sole independent claim on appeal and was directed to a method for the electrolytic polishing of a metallic substrate. The claimed method included a step of “applying a current at a voltage of 270 to 315 volts.”

The Examiner rejected claim 1 as obvious over Clasquin in view of Kodera. Regarding the claimed voltage of “270 to 315 volts,” the Examiner believed Clasquin described an overlapping voltage range based on Clasquin’s disclosure in ¶ 49 that “it has been found that higher voltage up to at least 150 volts can be used.” The Examiner interpreted the phrase “up to at least 150 volts” as teaching a range of “at least 150 volts” and pointed to Clasquin’s disclosure in ¶ 63 that “[c]urrent densities as high as at least 225,000 A/m2 can be used at applied voltages of 150 volts or more” for “nickel based alloy 718” as a support.

Appellant argued the Examiner’s interpretation of the phrase indicated that he ignored the preceding words “up to” and failed to read Clasquin’s disclosure in ¶¶ 49 and 63 in the context of Clasquin as a whole. In particular, Appellant argued “up to at least 150 volts” implied a ceiling of 150V, while the words “at least” provided some flexibility to that ceiling so that Clasquin suggested a maximum voltage that is slightly higher than 150V, but not as high as the lower boundary of 270V recited by claim 1. Appellant further argued that the disclosure in ¶ 49 served as an umbrella disclosure and that Clasquin’s specific working examples, including ¶ 63, would be understood by a skilled artisan as falling within that umbrella. In addition, Appellant noted Table 5 of Clasquin, which disclosed more than two dozen examples, used a maximum voltage of 150V.

The Board sided with the Appellant. The Board agreed that the Examiner’s interpretation of the phrase did not adequately account for the words “up to,” which, by their plain meaning, suggested a maximum, not a minimum. The Board noted Clasquin disclosed in ¶ 49 that for certain metals, polishing with voltages above 40V was undesirable because voltages above 40V resulted in loss of luster; however, certain other metals did not demonstrate the same problem and it was for those metals that “higher voltages up to at least 150 volts can be used.” Therefore, the Board held that, in context, the words “at least” did not wholly negate the preceding words “up to” but rather suggested the ceiling indicated by the words “up to” may be somewhat higher than 150V. The Board agreed with the Appellant that this interpretation was supported by the examples disclosed in Table 5 of Clasquin and was consistent with Clasquin’s other disclosures in, for example, ¶¶ 57 and 95.

Regarding Clasquin’s disclosure in ¶ 63, the Board noted “150 volts or more” – in isolation – was consistent with the Examiner’s understanding of Clasquin. However, the Board found that when it was read in view of Clasquin’s other disclosures, a skilled artisan would not have understood ¶ 63 as suggesting that any voltage above 150V could be used even for nickel 718, as evidenced by the dozen nickel 718 based compositions disclosed in Table 5, for which voltages only ranged from 9.7V to 150V.

Therefore, the Board agreed with the Appellant and found Clasquin as a whole as suggesting a voltage ceiling of approximately 150V, with some flexibility. Because 270V, the recited lower boundary of the voltage range, was 80% greater than the 150V suggested by Clasquin and because the Examiner did not establish a person of ordinary skill in the art would have understood Clasquin as teaching or suggesting voltages as high as those of claim 1, the Board reversed the Examiner’s obviousness rejection.

Takeaway:  Although the term at issue in Bagehorn is not a claim term but a phrase in a cited reference, the interpretation principle is the same. That is, terms and phrases should be given the interpretation as understood by a person of ordinary skill in the art in light of the disclosure as a whole. Nevertheless, the confusion could have been avoided if a phrase such as “up to around 150 volts” had used instead of “up to at least 150 volts.”

Judges:  J. C. Housel, C. C. Kennedy, and J. E. Inglese


June 16, 2021by Yanhong Hu

Section 101 specifies four patent eligible categories: process, machine, manufacture, and composition of matter.  However, the U.S. Supreme Court has long interpreted § 101 to exclude the so-called “judicial exceptions” as patent eligible subject matter.  Specifically, the judicial exceptions are laws of nature, natural phenomena, and abstract ideas (mathematical formulas, certain methods of organizing human activity such as fundamental economic practices, or mental processes).  Therefore, a claim determined to be directed to a judicial exception is patent ineligible unless it is found that the claim as a whole includes additional elements “that amount to significantly more than the judicial exception.”

The USPTO published a revised guidance on the application of § 101 in January 2019 followed by an update in October 2019.  The Guidance and the Update set forth a step-by-step eligibility analysis, in which Step 2 is the Supreme Court’s Alice/Mayo two-part test to determine whether a claim is patent ineligible because it is directed to a judicial exception.  In particular, Step 2A and Step 2B of the Office’s eligibility analysis correspond to the first and second parts of the Alice/Mayo test, respectively.

Step 2A is a two-prong inquiry.  Under Step 2A Prong 1, an examiner should look to whether a claim recites any judicial exceptions.  If the answer is yes, it does not mean that the claim is “directed to” the judicial exception; instead, the examiner should proceed to Step 2A Prong 2 to look to whether the claim recites additional elements that integrate the judicial exception into a practical application.  If so, the claim is not directed to the judicial exception and thus is patent eligible.  Only when the claim recites a judicial exception and does not integrate that exception into a practical application does the examiner proceed to Step 2B to consider whether the claim recites additional elements that are significantly more than the judicial exception.

Step 2A Prong 2 is similar to Step 2B in that both analyses involve evaluating a set of the same considerations to determine if the claim is still patent eligible due to the recited additional elements.  However, although consideration of whether the additional elements represent well-understood, routine, conventional activity is included under Step 2B, such consideration is specifically excluded under Step 2A Prong 2, because additional elements that represent well-understood, routine, conventional activity may integrate a recited judicial exception into a practical application.

Applying the Office’s eligibility analysis, the Patent Trial and Appeal Board (“Board”) in Ex parte Moritz (Appeal 2020-004626) considered the Examiner’s rejection of Applicant’s claims as being directed to patent-ineligible subject matter.

Claim 1, which was illustrative, was drawn to “[a] multiplexed method to identify proteins to which a test compound binds in a sample containing numerous proteins or for identifying a compound capable of binding to a target protein contained in a sample comprising numerous proteins, including said target protein.”  The method included steps (a)-(c), which, according to the Applicant, described a prior art method for determining interaction of a test compound with a single protein.  However, the Applicant argued the invention itself was directed to “an improvement which permits multiplexing” of the prior art method and the improvement lied in requiring that the sample comprised numerous proteins and that the step (c) of determining the concentration of multiple proteins was performed by SWATH-MS or SRM-MS.

The Board first analyzed whether the claim recited any judicial exceptions under Step 2A Prong 1.  The Board determined that the claim did not recite any method of organizing human activity such as fundamental economic practices or any mathematical concepts.  The Board noted that the Applicant did not dispute the Examiner’s contention that the claim recited metal processes and found it was “arguably conceivable that at least the claimed steps of identifying a protein that binds a test compound could be performed in the mind.”  The Board thus concluded “the claims recite the judicial exception of mental processes, and, thus, abstract ideas” under the broadest reasonable claim interpretation standard and proceeded to analyze the claim under Step 2A Prong 2.

The Board emphasized that under Step 2A Prong 2, the claim elements must be analyzed both individually and as an ordered combination to determine whether the additional elements integrated the recited abstract idea into a practical application, such as an improvement to technology or to a technical field.  To do that, the specification should be evaluated to determine “if the disclosure provides sufficient details such that one of ordinary skill in the art would recognize the claimed invention as providing an improvement.”  In addition, “the claim must be evaluated to ensure that the claim itself reflects the disclosed improvement.”

Applying to the application at hand, the Board noted that the claimed steps recited a method of identifying and quantifying proteins to which a test compound bound in a sample containing numerous proteins, where the interaction between the test compound and proteins was determined using SWATH-MS or SRM-MS.  The Board found that the Specification described the invention as an improvement in the technical field of assays (such as thermal shift assays) that assessed the interaction of a compound with a protein.  The Board also found that the Specification specifically explained that the claimed application of SWATH-MS or SRM-MS to prior art thermal shift assays overcame obstacles associated with using such assays on “complex protein samples.”  The Examiner recognized the claim included additional elements of the sample preparation and separations steps.  However, as held by the Board, the Examiner erred in considering whether the additional elements were “routine and conventional data gathering activity” under Step 2A Prong 2 and also erred in failing to consider the claim as a whole.  The Board agreed with the Applicant that when considered as a whole, the claim was directed to “an improvement in determining test compound interaction with proteins” and the additional elements integrated the recited judicial exception into a practical application.

Accordingly, the Board reversed the Examiner’s rejection, finding that the claimed subject matter was patent eligible.

Takeaway:  Although analysis under Step 2A Prong 2 is similar to the analysis under Step 2B, a critical difference between the two is that the Step 2A Prong 2 analysis, which determines whether a claim is “directed to” a judicial exception, is performed without considering what is well-understood, routine, conventional activity.  Moritz also illustrates that a claim, even if it recites a judicial exception, can be found not to be directed to the judicial exception under Step 2A Prong 2 and thus patent eligible, if the claim elements, when considered as a whole, represent an improvement in a specific technology that is described in sufficient detail in the specification for a skilled artisan to recognize.

Judges:  F. C. Prats, T. Chang, and C. M. Hardman


May 5, 2021by Yanhong Hu1

When faced with a limitation involving an open-ended numerical range, an examiner will not only analyze for definiteness under 35 U.S.C. § 112(b) but also scrutinize whether the limitation satisfies the written description requirement and the enablement requirement under § 112(a).  In Ex parte Qiu (Appeal 2020-001512), the Patent Trial and Appeal Board (“Board”) considered and reversed the Examiner’s rejection of Appellant’s claims for failing to comply with the written description requirement.

Claim 1 was illustrative and read (in part):

A composition comprising a compound wherein the compound consists of end groups R1 and R2 and at least m repeating segments of the following structures:

wherein Y is an anionic group selected from the group consisting of: sulfate, carboxylate, phosphate, phosphonate, and sulfonate, …; wherein the compound comprises substantially no other anionic pendant functional groups, except those selected from the group consisting of: sulfate, carboxylate, phosphate, phosphonate, and sulfonate, wherein the compound has a number average molecular weight of no more than 10,000 grams/mole and an average number of anionic groups of greater than 2.

Noting that the specification disclosed examples wherein the average number of anionic groups ranged from 2.09 to 15, the Examiner rejected claim 1 as failing to meet the written description requirement because the range “greater than 2” did not have an upper limit.  In response to Appellant’s rebuttal arguments citing the Federal Circuit’s decision in Anderson Corp. v. Fiber Composites, LLC, the Examiner alleged Anderson only applied to the question of enablement.

The Board clarified that Anderson applied to both questions of enablement and written description.  As stated in Anderson, “[o]pen-ended claims are not inherently improper” and “[t]hey may be supported if there is an inherent, albeit not precisely known, upper limit and the specification enables one of [ordinary] skill in the art to approach that limit.”  The Board agreed with Appellant that since the claim required an upper limit for the molecular weight of the compound (“no more than 10,000 grams/mole”), the specification as a whole enabled a skilled artisan to determine the inherent upper limit on the number of anionic groups for any particular compound circumscribed by the claimed requirements.  That is, the Board found the specification conveyed with reasonable clarity to those skilled in the art that, as of the filing date sought, Appellant was in possession of the invention.

Accordingly, the Board found the specification supported the claimed subject matter.

Takeaway:  As compared with a numerical range in which both the lower and upper limits are specified, an open-ended range offers a broader scope.  However, an open-ended numerical range often puts an examiner, like the Examiner in Qiu, on alert.  The Anderson decision assures that an open-ended range is supported and enabled if the unspecified limit is inherent and the specification is sufficient to enable one skilled in the art to approach that limit.  As a backup position, an applicant should consider including at least one dependent claim reciting a concrete endpoint to “close” the open range.

Judges:  C. Q. Timm, K. M. Hastings, and J. B. Robertson


March 26, 2021by Yanhong Hu

In Ex parte Hassler (Appeal 2020-001367), the Patent Trial and Appeal Board (“Board”) considered Appellant’s two arguments rebutting the Examiner’s obviousness rejection based on the combination of the primary reference (Fischmann) with the secondary reference (McNew).

Independent claim 1 illustrated the subject matter of the appealed claims and was directed to a method that included a step (a) of receiving an oxyanion-containing water comprising at least one non-metal-containing oxyanion and a subsequent step (b) of contacting the oxyanion-containing water with a separate rare-earth-element-containing component to remove more than 50% of the oxyanions from the oxyanion-containing water.  The claim further limited the non-metal-containing oxyanion to an anion that contained one or more particular species recited in a Markush group.

The Examiner admitted Fischmann, which disclosed step (a), failed to teach a separate component containing a rare-earth element as claimed in step (b) and thus resorted to McNew for the admitted deficiency.  Appellant first argued Fischmann did not constitute prior art because the claimed subject matter enjoyed priority to applications that predated Fischmann.  Secondly, Appellant argued even if Fischmann constituted prior art, the Examiner’s substitution of McNew’s composition into the process of Fischmann was improper.

The Board reversed the obviousness rejection because the Board agreed with Appellant’s second argument.  However, the Board sided with the Examiner regarding Appellant’s first argument.  The Board’s analysis of Appellant’s first argument involving the written description and enablement requirements of 35 U.S.C. § 112(a) (or pre-AIA § 112, ¶ 1) is the focus of this blog.

Appellant argued the application at issue had an earlier effective filing date because it claimed priority to two provisional applications (“the Hassler provisionals”), which incorporated by reference three earlier filed non-provisional applications (“the incorporated applications”).  Appellant argued all the incorporated applications and the Hassler provisionals defined the terms “oxyanion” and “target material-containing oxyanion” in the same way.

The Examiner contended the claim could not be afforded priority of the Hassler provisionals because the Hassler provisionals did not support the claimed subject matter in a manner that complied with the written description requirement of § 112(a).  The Examiner explained the Hassler provisionals merely described the oxyanions generally as AxOy with A being a metal, metalloid, or non-metal but did not disclose any species of non-metal oxyanions other than selenium.  The Examiner similarly found the incorporated applications failed to disclose the Markush species recited in claim 1.

Appellant did not dispute the Examiner’s contention that the Hassler provisionals failed to expressly disclose the particular Markush species.  However, Appellant argued “the fact that the Hassler provisionals do not define non-metal oxyanions other than selenium oxyanions as ‘target-material containing’ oxyanions does not limit the scope of the genus of ‘oxyanions’ generally [described therein].”  Appellant continued, “it [is] well known to those of ordinary skill in the art that the term ‘oxyanion’ referred to any anion ‘containing one or more oxygen atoms bonded to another element.’”  Citing Regents of the University of California v. Eli Lilly, 119 F.3d 1559, 1568 (Fed. Cir. 1997) and relevant MPEP sections, Appellant further argued that “in assessing a disclosure for compliance with 35 U.S.C. § 112(a), … ‘[w]hat is conventional or well known to one of ordinary skill in the art need not be disclosed in detail’” and that the general chemical formula AxOyz- disclosed in the Hassler provisionals eliminated any ambiguity in that “such a formula, even standing alone, provides adequate disclosure for the genus of oxyanions because, ‘[i]n claims involving chemical materials, generic formulae usually indicate with specificity what the generic claims encompass [and] [a]ccordingly, such a formula is normally an adequate description of the claimed genus.”

The Board disagreed and found Appellant confused the written description requirement of § 112(a) with the enablement requirement of § 112(a).  The Board noted that the enablement requirement was more indulgent than the written description requirement.  The Board acknowledged a specification did not necessarily need to disclose what was well-known and conventional in order to satisfy the enablement prong of § 112(a).  However, the Board emphasized written description and enablement were separate requirements.  In particular, “[a]dequate written description means that the applicant, in the specification, must ‘convey with reasonable clarity to those skilled in the art that, as of the filing date sought, he or she was in possession of the [claimed] invention.’”  The Board further noted a specification must provide some guides or “blaze marks” that disclosed the claimed invention “specifically, as something appellants actually invented.”  The Board did not find Appellant’s argument about whether oxyanions, as a class, were well known to those skilled in the art addressed the separate inquiry of whether the Hassler provisionals provided adequate written description to establish the claim to priority.

Because “one cannot disclose a forest in the original application, and then later pick a tree out of the forest and say here is my invention,” Purdue Pharma L.P. v. Faulding Inc., 230 F.3d 1320, 1326 (Fed. Cir. 2000), the Board did not find Appellant sufficiently demonstrated that any of the earlier filed applications conveyed with reasonable clarity to those skilled in the art that, as of the filing date sought, Appellant was in possession of the claimed Markush species.  Accordingly, the Board held Fischmann constituted prior art.

Takeaway:  To satisfy the written description requirement, a specification must describe the claimed invention in sufficient detail that one skilled in the art can reasonably conclude that the inventor had possession of the claimed invention at the filing date sought.  For a claim to comply with the written description requirement or to be entitled to a priority date, each claim limitation must be expressly or inherently supported in the originally or previously filed disclosure.  When an explicit limitation in a claim is not present, it must be shown that those skilled in the art would have understood that the description requires that limitation.  As illustrated by Hassler, in the chemical art, a structural chemical formula that is not sufficiently detailed fails to show applicant was in possession of the claimed invention as of the filing date sought.

Judges:  T. J. Owens, B. W. Baumeister, and B. D. Range


February 19, 2021by Yanhong Hu

In Ex parte Gomez (Appeal 2020-001462), the Patent Trial and Appeal Board (“Board”) considered an Examiner’s obviousness rejection based on an allegedly overlapping range and, alternatively, optimization of a result-effective variable.  The Board found neither of the Examiner’s two rationales were persuasive.

The sole independent claim 19 illustrated the claimed subject matter on appeal and was drawn to a method of improving the scratch resistance of a glass.  The claimed method included, among other steps, a step of “forming a porous silica-rich layer on the surface of the glass, wherein the silica-rich layer extends from the surface to a depth of greater than or equal to 100 nm to less than or equal to 600 nm into the glass.”

The Examiner rejected claim 19 as obvious over Amin.  The Examiner found Amin disclosed the formation of a porous silica-rich layer on a surface of a glass by treating the surface with an acid to improve the scratch resistance of the glass.  The Examiner noted Amin disclosed the preferred depth of the silica-rich layer was less than 50 nm, which was outside the claimed depth range.  However, the Examiner contended the claimed depth of the silica-rich layer would still have been obvious over Amin under two rationales.

First, the Examiner noted Amin disclosed that the surface of the glass had a root mean square (RMS) roughness of 50-5000 nm.  While acknowledging “RMS roughness is not directly equivalent to the depth,” the Examiner believed “given that it is the root mean square of the peak-to-valley heights (i.e. root mean square of the depth across the surface) it is apparent that a RMS roughness of 50–5000 nm overlaps [the recited depth range].”

Second, the Examiner found the depth of the silica-rich layer was a result-effective variable because Amin disclosed that the silica-rich layer was selected “based on the desired balancing between the improved adhesion of the subsequent layer and a depth whereby the mechanical properties are not affected.”  The Examiner then concluded it would have been obvious to optimize the depth and arrive at the claimed range “to obtain the desired chemical and mechanical properties.”

The Board found Amin’s disclosure of the RMS roughness of 50-5000 nm was related to an alternative embodiment of Amin’s invention that involved forming a glass article having a textured or patterned surface disposed between a chemically strengthened layer and an exterior amphiphobic layer.  The Board pointed out the Examiner did not provide technical reasoning supported by objective evidence to prove that RMS roughness corresponded to, or was equivalent to, the depth of a silica-rich layer into a glass.  Because the Examiner’s allegedly overlapping range disclosed in Amin appeared to relate to a variable irrelevant to the claimed depth of silica-rich layer, the Board concluded the Examiner’s assertion of overlap appeared to be based on speculation, which did not constitute a sufficient basis for establishing prima facie obviousness.

In addressing the Examiner’s allegation of optimization of a result-effective variable, the Board found that Amin described conducting an acid treatment to remove chemically exchanged (potassium) ions from the surface of a glass to a depth typically of ≤ 50 nm, “whereby the mechanical performance of the chemically strengthened glass (for example, strength, scratch resistance, impact damage resistance) is not affected.”  Amin further disclosed the depth was preferably 5-15 nm and described a specific example in which the depth was only 10 nm. The Board noted these disclosed depth values were “all far below” the recited depth range and concluded “[one] of ordinary skill in the art would have understood this disclosure to implicitly indicate that removing chemically exchanged ions to a depth greater than 50 nm may adversely affect the mechanical performance of the glass.”  The Board did not find the Examiner provided sound technical reasoning supported by objective evidence to establish that a skilled artisan would have disregarded Amin’s explicit disclosure of a typical depth of ≤ 50 nm and implicit disclosure that removing ions to a greater depth might adversely affect the mechanical performance of the glass.

Citing In re Sebek, the Board emphasized that “[when] the prior art disclosure suggests the outer limits of the range of suitable values, and that the optimum resides within that range, and where there are indications elsewhere that in fact the optimum should be sought within that range, the determination of optimum values outside that range may not be obvious.”  In Gomez, the claimed depth range was outside an optimum range of ≤ 50 nm disclosed in Amin and Amin taught in multiple places that the depth should be within the optimum range.  In other words, Amin appeared to teach away from the claimed depth range.  Therefore, the Board also rejected the Examiner’s optimization rationale.

Because the Examiner did not provide a sufficient factual basis to support his conclusion that the claimed depth of the silica-rich layer would have been obvious over Amin, the Board reversed the rejection.

Takeaway:  Claiming a range is particularly common in chemical arts.  If a claimed range does not overlap a prior art range, examiners will sometimes argue the parameter of the range is a result-effective variable that could be optimized to reach the claimed range.  As illustrated by Gomez (see also Nonobviousness: PTAB Rejects Examiner’s Optimization by Routine Experimentation Rationale), even if the parameter passes the muster to be a result-effective variable, the optimization rationale will not stand if the prior art implicitly teaches away from the claimed range by disclosing a non-overlapping optimum range and encouraging one to seek a value within the optimum range.

Judges:  R. H. Delmendo, M. P. Colaianni, and J. E. Inglese


January 13, 2021by Yanhong Hu

Obviousness requires both a reason to modify or combine prior art to achieve a claimed invention and a reasonable expectation of success.  Evidence showing there was no reasonable expectation of success would support a conclusion of nonobviousness.  In Ex parte Hewes (Appeal 2019-006474), the Patent Trial and Appeal Board (“Board”) reversed the Examiner’s obviousness rejection because the Board found Appellant’s evidence showing no reasonable expectation of success was persuasive.

The claimed invention in Hewes, as recited in the illustrative claim 17, was directed to “a method for treating a BcrAbl positive leukemia in a subject that is resistant to imatinib.”  Imatinib is a drug typically used to treat patients with chronic myelogenous leukemia (CML) because it blocks an abnormal protein called “the tyrosine kinase protein ‘BcrAbl’” that drives overproduction of abnormal white blood cells characteristic of leukemia.  Some patients, however, develop resistance to imatinib “due to point mutations in the bcr/abl gene.”  F317L is such a mutation.  The claimed method at issue comprises “administering to the subject a therapeutically effective amount of [bosutinib], wherein the subject has a mutation in BcrAbl protein selected from F317L.”

The Examiner rejected claim 17 as obvious over Manley and over Boschelli ‘780 in view of Shah.

In the obviousness rejection over Manley, the Examiner admitted Manley did not disclose a single embodiment regarding administration of bosutinib to a patient suffering from imatinib resistant BcrAbl positive leukemia.  However, the Examiner asserted a skilled artisan would have been motivated to practice the claimed method with reasonable expectation of success based on Manley’s teaching that bosutinib was one of a class of promising new inhibitor compounds for treating imatinib-resistant CML, that imatinib resistance was due to emergence of clones expressing mutant proteins, and that F317L was alleged to be among the “most frequently occurring mutants.”

Appellant contended that Manley did not suggest any promising new CML drug, including bosutinib, could treat imatinib-resistant CML associated with F317L and that F317L was actually a rare mutation.  More importantly, Appellant argued for unpredictability in treatment of imatinib-resistant leukemia in patients with the F317L mutation, citing, in particular, the affidavit by Dr. Murray.  The Murray affidavit testified that the F317L mutant was especially resistant to treatment even with second generation drugs like dasatinib and nilotinib, citing several references.  The Murray affidavit explained that different patients, even with the same mutation, were known to display different clinical response upon treatment.  Therefore, along with other documentary references, the Murray affidavit proved that imatinib resistance arising from mutations of the Bcr-Abl gene was poorly understood at the time of the invention.  The Murray affidavit also testified that “clinical findings show F317L to be a[n] imatinib/dasatinib-resistant mutation” although preclinical models might have predicted drug potency against F317L mutants; and thus proved the preclinical models in this area were poor predictors of clinical efficacy and success.

Although the Board agreed with many of the Examiner’s readings of Manley, the Board agreed with Appellant that none of the second-generation drugs in Manley were disclosed as effectively treating imatinib-resistant CML associated with the F317L mutation.  The Board found Appellant’s argument and supporting evidence that showed a lack of predictability in treating imatinib-resistant patients particularly with the F317L mutation were convincing.  The Board noted that Appellant’s evidence, especially Dr. Murray’s testimony, “calls into significant doubt whether the ordinarily skilled person would have reasonably expected success with bosutinib when other second-generation, Bcr-Abl/Src inhibitors were known and shown to be ineffective in treating subjects with the F317L mutation.”  The Board found that the Examiner provided no persuasive rebuttal in the face of Appellant’s argument and evidence.

In addressing the Examiner’s characterization of the Murray affidavit as “merely opinions” on the state of the art, the Board noted that the affidavit could not be summarily swept aside in this way because “Dr. Murray cites repeatedly to the scientific literature[, including Manley and Shah, which are the references asserted by the Examiner,] in support of his opinions, grounding those opinions in an adequate factual basis.”  The Board found it was the Examiner who failed to “grapple persuasively with Dr. Murray’s opinions or the facts on which they are based.”

The Board thus concluded that even if the Examiner’s reasoning provided some motivation to treat patients with the F317L mutation with bosutinib, considering the totality of the evidence, the Examiner’s rejection failed “on the issue of reasonable expectation of success.”  Accordingly, the Board reversed the Examiner’s obviousness rejection over Manley.

Regarding the obviousness rejection over Boschelli ‘780 in view of Shah, the Board found it was unsustainable for substantially the same reason.

Takeaway:   As noted by the Board in Hewes, there are two different inquiries in an obviousness rejection – the motivation and the reasonable expectation, with the latter referring to the likelihood of success in modifying prior art to reach a claimed invention.  A determination of obviousness is not proper if, upon consideration of all the evidence, the outcome would not have been reasonably predictable and there would not have been a reasonable expectation of success at the time of the invention.  As illustrated by Hewes, such evidence could be in the form of an expert’s affidavit.  To provide a probative expert’s affidavit, the expert should set up facts suggesting the unpredictability and corroborate her opinions with scientific literature preferably authored by other people skilled in the field.

Judges:  D. E. Adams, E. B. Grimes, and T. G. Majors


December 23, 2020by Yanhong Hu

While a judgment on obviousness is in a sense necessarily a reconstruction based on hindsight reasoning, such a reconstruction is improper if it includes knowledge gleaned only from applicant’s disclosure.  In Ex parte Shelton (Appeal 2020-001178), the Patent Trial and Appeal Board (“Board”) reversed the Examiner’s obviousness rejection because the Examiner improperly resorted to hindsight.

Claim 1 was illustrative and was drawn to a staple cartridge assembly for use with a surgical stapler.  The claimed staple cartridge assembly contained a cartridge body, a biocompatible, bioabsorbable adjunct material, and “an effective amount of at least one medicant disposed within and releasable from the adjunct material, the at least one medicant including an activator material configured to be activated within the body of the patient by an activator located outside the body of the patient, the activation of the at least one medicant allowing monitoring of the adjunct material after its delivery to the tissue, the activator material being configured to be activated by a magnetic field induced by the activator.”

The Examiner rejected claim 1 as obvious over a staple cartridge assembly described in Schmid as modified by adding an activator material described in Dormer.  The Examiner alleged it would have been obvious to a skilled artisan to “have provided Schmid’s [staple cartridge assembly] with the features as taught by Dormer in order to target deliver[y] of a medicament.”

Appellant countered in the Appeal Brief that there was no reason for the proposed modification and the Examiner’s rejection was based on improper hindsight.  Specifically, Appellant contended Dormer’s magnetic targeted delivery was wholly unnecessary because “Schmid already provides targeted delivery of its medicament.”

In response, the Examiner acknowledged Schmid had “an activator, such as a fluid activator or an oxidizing agent, for a controlled release of the medicament” but alleged that Dormer was relied upon “to show the mode of activating a material, such as using a magnetic field.”  The Examiner thus provided a second rationale for her proposed modification – it would have been obvious to “apply Dormer’s mode of activation, i.e.[, a] magnetic field, to Schmid’s adjunct material in order [to] control the release of the medicament.”

The Board noted that, in Dormer, the site of delivery was different from the site of treatment and Dormer used magnetically-susceptible nanoparticles to move medicants from the site of delivery to the site of treatment; while Schmid had its medicants already at the site of delivery and the site of treatment.  Because Schmid already provided targeted delivery of its medicament, the Board sided with Appellant and did not find the Examiner’s first reason for her proposed modification persuasive.

The Board further noted Dormer’s magnetically-susceptible nanoparticles and the equipment necessary to generate a magnetic force to move or oscillate the nanoparticles to control the release of its medicant seemed more complex than Schmid’s use of an oxidizing agent to control the release of its medicant at the site of treatment.  The Board found that the Examiner did not provide a reason why it would have been obvious to substitute Schmid’s simple mode of activation for Dormer’s more complex one.  Therefore, the Board was also not persuaded by the Examiner’s second reason for her proposed modification.

Because the Examiner did not articulate a persuasive reason supported by rational underpinning for combining Schmid and Dormer, the Board concluded that “it is more likely than not that the Examiner improperly resorted to hindsight in reaching a conclusion of obviousness.”

The Board emphasized it was not proper to base a conclusion of obviousness upon facts gleaned only through hindsight, noting that to use an invention as a template for its own reconstruction when the prior art did not contain or suggest that knowledge was “an illogical and inappropriate process by which to determine patentability” and that “[t]he invention must be viewed not after the blueprint has been drawn by the inventor, but as it would have been perceived in the state of the art that existed at the time the invention was made.”  Accordingly, the Board reversed the Examiner’s obviousness rejection.

Takeaway:  Due to the very nature of the process of patent application examination, it is often difficult for examiners to avoid the tendency to resort to “hindsight” based upon applicant’s disclosure.  However, such a reconstruction is proper only if it takes into account knowledge that was within the level of ordinary skill in the art at the time of the invention and does not include knowledge gleaned only from applicant’s disclosure.  As illustrated by Shelton, when the examiner’s reason for a proposed modification lacks support in the prior art and appears to be only drawn from applicant’s own disclosure, the rejection could be rebutted on the ground of improper hindsight.

JudgesC. N. Greenhut, M. L. Hoelter, and A. R Reimers


November 23, 2020by Yanhong Hu

A threshold issue for the Patent Trial and Appeal Board (“Board”) to resolve is often claim interpretation.  It is well-settled that claims must be “given their broadest reasonable interpretation consistent with the specification” during patent examination.  In Ex parte Awad (Appeal 2019-005866), the Board reversed the Examiner’s obviousness rejection because the Board found the rejection was based on an unreasonably broad claim interpretation when the relevant claim language was read in light of the specification.

Claim 1 was illustrative and was drawn to a flexible solar panel, which contained a polymer matrix and a plant extract completely incorporated in the polymer matrix and “being a green-colored extract of B. vulgaris subsp. cicla, wherein the extract includes chloroplasts.”

The Examiner rejected the claimed solar panel as obvious over Ochiai in view of Pavokovic and Yang.  In particular, the Examiner found Ochiai taught a solar panel containing a PVA matrix and a plant extract completely incorporated in the polymer matrix wherein the extract included green-colored chloroplasts.  The Examiner admitted Ochiai did not disclose that the plant extract was “a green-colored extract of B. vulgaris subsp. cicla.”  However, the Examiner found Pavokovic taught that betalains, such as those from B. vulgaris subsp. cicla, were useful as “natural pigments” in solar cells and found Yang taught that incorporating chlorophyll-containing plant extracts in a PVA polymer matrix stabilized the extracts against light- and oxygen-induced damage.

In response to Appellant’s arguments that betalains described in Pavokovic were “classified in two groups: red-violet betacyanins and yellow betaxanthins” and that Pavokovic did not teach “the usage of a green, chloroplast-containing extract of B. vulgaris subsp. [cicla] in a [dye-sensitized solar cell],” the Examiner argued he did not rely on Pavokovic “for teaching the entirety of the claimed plant extract,” instead, he relied on Pavokovic “only to teach that betalain extracts of B. vulgaris subsp. cicla are useful as natural pigments in solar cells to convert radiant energy into electric energy.”  The Examiner argued “Ochiai teaches a plant extract that is green and includes chloroplasts” and further argued “even if the betalains of B. vulgaris subsp. cicla are colors other than green, the final product created from the combination of the prior art references still contains a plant extract comprising the green-colored chlorophyll chloroplasts taught by Ochiai because these betalains are added to Ochiai’s plant-extract composition.”

Therefore, as noted by the Board, the Examiner interpreted the claim limitation of the plant extract “being a green-colored extract of B. vulgaris subsp. cicla, wherein the extract includes chloroplasts” to encompass any combination of plant extracts “as long as the final combination (a) is green-colored, (b) includes a B. vulgaris subsp. cicla extract, and (c) includes chloroplasts.”

The Board found such interpretation was broader than what was reasonable when the claim language was read in light of the specification.  Specifically, the Board noted that the specification stated that the field of the invention related “particularly to a flexible solar panel including an extract of chard (B. vulgaris subsp. cicla)” and that at no point did the specification discuss extracts from any plant other than B. vulgaris subsp. cicla.  The Board further found the specification specifically taught “a green colored extract of B. vulgaris subsp. cicla” and each of the working examples used an extract from B. vulgaris subsp. cicla, not from any other plant and not mixed with any other plant extract.

The Board thus concluded that, when the claim language was interpreted in light of the specification, the broadest reasonable interpretation of the claim limitation required “an extract from B. vulgaris subsp. cicla that itself is green-colored and also contains chloroplasts; i.e., the chloroplasts are derived from B. vulgaris subsp. cicla.”  The Board further explained “‘being’ in the quoted limitation is construed to mean ‘consisting of’: the plant extract consists of a green-colored extract of B. vulgaris subsp. cicla, wherein the extract includes chloroplasts.”  The Board explicitly pointed out that “[to] interpret the quoted limitation to encompass a mixture of plant extracts would be inconsistent with the specification’s disclosure.”

With the correct claim interpretation, the Board further found none of the cited references disclosed a green-colored extract from B. vulgaris subsp. cicla that included chloroplasts as required by the claim limitation.  Because the Board did not find the Examiner had shown the plant extract as required by the claim would have been obvious over the cited references or that the prior art would have provided a reason to use such an extract in the claimed solar panel, the Board reversed the obviousness rejection.

Takeaway:  U.S. examiners are required to give claims their broadest reasonable interpretation in light of the specification.  However, in practice, they sometimes fail to consider whether their “broadest” interpretation of the claim language is “reasonable in light of the specification.”  Therefore, it is advisable to scrutinize an Examiner’s claim interpretation especially when there is a complicated claim limitation that includes multiple sub-features.  As illustrated by Awad, examiners sometimes fail to recognize that sub-features are related, instead treating them separately. This approach can lead to unreasonably broad interpretations.

JudgesE. B. Grimes, L. M. Gaudette, and L. Ren