February 3, 2023by Jacob Doughty

Ex parte Fox is a recent decision of the Patent Trial and Appeal Board (PTAB) addressing the interpretation of a Markush group in a claim rejected for anticipation and obviousness.  

The claim at issue was directed to “[a] cleaning solution comprising one or more solvents selected from the group consisting of acetoacetates, alcohols, glycol ethers, glycol esters, terpenes, and water…” The claim also required other components and properties. 

The examiner identified a cleaning solution in the prior art which included some of the solvents listed in the claim. However, the prior art cleaning solution required a further solvent, “at least one oxyisobutyric acid ester.” The examiner asserted that, although at least one of the listed solvents must be present, the “comprising” language in the claim permitted the presence of additional solvents in the cleaning solution.  

The examiner supported his position by citing MPEP 2111.03.II, which, in turn, cites In re Crish, 393 F.3d 1253 (Fed. Cir. 2004). The examiner relied on the following description of the Crish case from the MPEP:  

In determining the scope of applicant’s claims directed to “a purified oligonucleotide comprising at least a portion of the nucleotide sequence of SEQ ID NO:1 wherein said portion consists of the nucleotide sequence from [521] to 2473 of SEQ ID NO:1…” the court stated that the use of “consists” in the body of the claims did not limit the open-ended “comprising” language in the claims… 

The PTAB stated that a case cited in the same paragraph of the MPEP relied on by the examiner, Multilayer Stretch Cling Film Holdings, Inc. v. Berry Plastics Corp., 831 F.3d 1350, (Fed. Cir. 2016), included a fact pattern much closer to the claim on appeal. The PTAB stated that Crish was distinguishable from the claims on appeal, because Crish did not involve a Markush group of distinct alternatives from which to select. 

Relying on the Multilayer case, the PTAB noted that the use of the transitional phrase “consisting of” to set off a patent claim element creates a very strong presumption that that claim element is closed and therefore excludes any elements, steps, or ingredients not specified in the claim. Thus, if a patent claim recites “a member selected from the group consisting of A, B, and C,” the member is presumed to be closed to alternative ingredients D, E, and F. In the claim on appeal, the “member” was the “solvent,” so the claim was closed to solvents other than those specifically recited in the Markush group – even though the claimed cleaning solution was open to containing other non-solvent elements. 

When the claim on appeal was properly construed, the prior art was not sufficient to anticipate or render obvious the claim, because the prior art required the presence of “at least one oxyisobutyric acid ester” solvent, i.e, a solvent that was not recited in the Markush group of the claim.  

Takeaway: Markush groups are frequently used to define components of composition. It is important to be intentional when drafting Markush group to control what is within and outside the scope of the claim. In thinking about a claim drafted in typical Markush format, “an X selected from the group consisting of A, B, and C,” attention is often focused on A, B, and C, which define what must be present. However, care must be taken in defining X which indicates what will be excluded from the claim. A broad X may define over the prior art but may also make design-around compositions easy to identify.  

Judges: Cashion, McGee, Inglese


June 10, 2022by Jacob Doughty

Pavo Sols. v. Kingston Tech. Co., No. 2021-1834 (Fed. Cir. June 3, 2022), is a recent decision of the Federal Circuit considering, inter alia, whether a district court acted appropriately in “judicially correcting” an error in claim language. Kingston was found by the district court to have willfully infringed the judicially corrected claim.

The claim at issue recited:

A flash memory apparatus comprising:

a flash memory main body including a rectangular shaped case within which a memory element is mounted, a[] USB (Universal Serial Bus) terminal piece electrically connected with the memory element and installed at a front end of the case in a projecting manner, and a hinge protuberance formed on at least one side of the case; and

a cover including [a] pair of parallel plate members facing each other and spaced by an interval corresponding to the thickness of the case, the cover having an open front end and a closed rear end with a pair of lateral side openings; the parallel plate members having at least one hinge hole receiving the hinge protuberance on the case for pivoting the case with respect to the flash memory main body, whereby the USB terminal piece is received in an inner space of the cover or exposed outside the cover.

As emphasized above, the claim requires cover features that permit the case to pivot with respect to the flash memory main body.  However, the case is part of the flash memory main body and not part of the cover, so it is unclear how the features of the cover could cause a part of the flash memory main body to pivot with respect to itself (or another part thereof). The district court found that it was apparent from the claim language that “pivoting the case” should be “pivoting the cover” and judicially corrected the language in its claim construction order.

The Federal Circuit noted that it is permissible for a court to correct “an obvious minor typographical or clerical error” in a patent claim “only if (1) the correction is not subject to reasonable debate based on consideration of the claim language and the specification and (2) the prosecution history does not suggest a different interpretation of the claims.”

Kingston argued that the error could not possibly be minor because the correction replaced one structural element with another and broadened the claims. Kingston further argued that alternative corrections were plausible in view of the claim language, specification, and prosecution history.

The Federal Circuit found that its precedent did not prohibit corrections that resulted in changes to recited structure. Further, the Federal Circuit found Kingston’s arguments with respect to broadening and plausible alternative corrections (and the supporting expert testimony) to be insufficient to raise a reasonable debate about claim scope.

Having affirmed the district court’s correction of the claim, the Federal Circuit concluded that the district court’s finding of willful infringement was also appropriate. Specifically, “[w]e hold, however, that reliance on an obvious minor clerical error in the claim language is not a defense to willful infringement.”

Takeaway: When performing a clearance or freedom-to-operate analysis, patent counsel often search for “errors” made in drafting or prosecution of a patent application that could result in a narrow construction or estoppel that will give a client comfort that a finding of infringement is unlikely. However, it is important not to be too strict or literal in this analysis. If the intended meaning of claim term is clear using common sense, it may be risky to base a conclusion of non-infringement on errors in a claim even if they seem significant.

Judges: Lourie, Prost, Chen


April 19, 2022by Mamoru Kakuda

2022年4月4日、CAFCは独立クレームの範囲は従属クレームに記載された態様を含むべきであるという原則を適用したクレーム解釈に基づく判決をしました (Littelfuse, Inc. v. Mersen USA EP Corp. (Fed. Cir. April 4, 2022))。


December 13, 2021by Jacob Doughty

AstraZeneca AB v. Mylan Pharm., 2021-1729 (Fed. Cir. Dec. 8, 2021), is a recent decision of the Federal Circuit interpreting the scope of a numerical limitation in a claim.

The claims on appeal in AstraZeneca were directed to pharmaceutical formulations for administration via pressurized metered dose inhalers. The formulations required a formulation stabilizer, PVP K25, and recited “the PVP K25 is present at a concentration of 0.001% w/w.”

The district court interpreted 0.001% w/w as encompassing 0.001% w/w “within one significant figure” – i.e., any value that could be rounded up or down to 0.001% w/w, or 0.0005% to 0.0014% w/w. The Federal Circuit disagreed and interpreted 0.001% w/w as “that precise number, with only minor variations” – i.e., 0.00095% to 0.00104% w/w. A further alternative was offered in Judge Taranto’s dissent.

The Federal Circuit indicated that, in the abstract, the ordinary meaning of 0.001% w/w was consistent with the district court’s interpretation of 0.0005% to 0.0014% w/w (“This is a standard scientific convention, and numbers falling within that range would typically be rounded up or down to 0.001%.”). However, the Federal Circuit found that

…taken as a whole, the intrinsic record supports a narrower construction of 0.001% to reflect that term’s application to the PVP concentration in particular, and the testing evidence in the written description and prosecution history showing that very minor differences in the concentration of PVP—down to the ten thousandth of a percentage (fourth decimal place)—impact stability.

Of particular importance to the Federal Circuit were experimental results in the specification showing significant changes in stability between a composition including 0.001% w/w PVP and a composition including the more precisely defined 0.0005% w/w PVP. The patentee made arguments about the results during prosecution and cancelled claims reciting, e.g., “0.0001% to 0.001% w/w” PVP and “0.0001%, 0.0005%, or 0.001% w/w” PVP. The Federal Circuit further noted that the patentee could have used the term “about” to modify of 0.001% w/w but chose not to.

Based on the Federal Circuit’s construction, the case was remanded for further consideration of infringement.

In his dissent, Judge Taranto found the majority’s approach too exacting. He argued that the disclosure of more precise values in the specification (e.g., 0.0005% w/w PVP) was not a disclaimer of the ordinary meaning of 0.001% w/w PVP. In Judge Taranto’s view, applicant’s arguments during prosecution with respect to stability at most required an exclusion of 0.0005% w/w PVP from the literal scope of 0.001% w/w.

Takeaway: This decision – particularly when the majority and dissent opinions are compared – does not offer much clarity as to how precisely a numerical value in a claim will be interpreted. There appears to be consensus that the starting point is “within one significant figure.” However, based on the majority’s decision, even the mention of more precise values in the specification or prosecution history can impute an additional significant figure to a claimed value. Practitioners should at least be wary of the risks of using different degrees of precision for different data points/values in the specification and claims and consider explicitly defining the degree of error intended for claimed values in the specification.

Judges: Taranto, Hughes, Stoll (Taranto dissenting)


November 29, 2021by Beau Burton

In Ex parte Talamoni (Appeal No. 2020-006553), the Patent Trial and Appeal Board (“Board”) rejected an Examiner’s claim construction overriding the phrase “derived from the reaction product of” with “comprising.”

The independent claim on appeal read:

A composition comprising an acrylic adhesive derived from the reaction product of

(a) an acrylic ester of monohydric alcohol having an alkyl group of the 5 to 10 carbon atoms; and

(b) a nonpolar acrylic monomer having a solubility of less than 9.2 as measured by the Fedors method using a homopolymer of the nonpolar acrylic monomer,

wherein the reaction product has a side chain crystallinity.

The Examiner rejected the claim as anticipated by or, in the alternative, obvious in view of a reference that disclosed a terpolymer produced from monomers (a) and (b) and 0.5–5 wt% of a monomer (c) (a monoolefinically unsaturated ketone). The Examiner argued the “side chain crystallinity” although not disclosed would be present in view of In re Spada (i.e., “[w]hen the PTO shows a sound basis for believing that the products of the applicant and the prior art are the same, the applicant has the burden of showing that they are not”). The Board disagreed.

At the outset, the Board found that the phrase “derived from the reaction product of” monomers (a) and (b) would be understood by those of skill in the art to exclude the terpolymer of the prior art derived from monomers (a), (b), and (c). The Board did agree that the use of “comprising” in the preamble opened the claim up to additional unrecited ingredients such as tackifiers but it did not override or expand the requirement for a reaction product obtained from the two monomers (a) and (b). Accordingly, the Board reversed the anticipation rejection.

As for obviousness, the Board found that the prior art taught away from omitting monomer (c) since it taught the monomer (c) provided the terpolymer with stability and stated, “if the amount of monomer (c) is less than 0.5 mass %, an insufficient effect is produced by the addition.” With no reason for why a person of ordinary skill in the art would have been motivated to omit monomer (c) from the prior art, the Board reversed the obviousness rejection.

Finally, the Board emphasized that the Examiner was not entitled to rely on the presumption from Spada because Appellant’s claim did not cover a reaction mixture containing monomer (c) and the breadth of monomer (c) in terms of the amount and potential species was too broad to conclude that the prior art’s terpolymer was substantially identical to the claimed copolymer of monomers (a) and (b).

Takeaway: In re Talamoni is notable for two reasons. First, the Board found the phrase “derived from the reaction product of … (a) … and (b)” to be closed. While savvy US applicants are accustomed to “comprising” and “consisting of,” phrases like this tend to be more common in applications originating outside the US. Accordingly, it is a good practice to replace uncommon transitional phrases with the corresponding US equivalent (e.g., comprising, consisting essentially of, or consisting of) to limit these types of disputes. And second, the Board correctly found that use of the transitional phrase “comprising” in the preamble did not render the following transitional phrase obsolete. Unfortunately, this type of interpretation before an Examiner is not uncommon, but it is promising to see the Board consistently reaching the correct conclusion. See, e.g., (PTAB rejecting an Examiner’s attempt to construe “comprising … a single odorant chamber” to allow for a plurality of chambers).

Judges: G. Best, N. Wilson, M. Cashion, Jr.


November 12, 2021by Matthew Barnet

During patent prosecution in the U.S., claims are given their broadest reasonable interpretation consistent with the specification. Ex parte Adel (Appeal No. 2020-006165) is a recent case in which the Patent Trial and Appeal Board (“Board”) found an examiner’s broad interpretation to be unreasonable.

Independent claim 1 recited (in part):

A process for manufacturing an edible water-in-oil emulsion, comprising the steps of:

a) providing a water-phase;

b) providing a liquid oil;

c) providing a fat powder comprising hardstock fat;

d) providing a hardstock fat in liquid form;

e) mixing the fat powder comprising hardstock fat, the hardstock fat in liquid form, and the liquid oil to form an oil-slurry, wherein the hardstock fat in liquid form is completely liquid before contact with the fat powder; …

The examiner rejected the claims as obvious over a combination of references. In the examiner’s proposed combination, the hardstock fat in liquid form included a portion that had crystallized (i.e., solidified) before contacting the fat powder.

The appellant argued that the existence of the crystallized portion meant that the hardstock fat in liquid form was not completely liquid before contact with the fat powder, contrary to the requirement of claim 1.

The examiner took the position that the hardstock fat containing the crystallized portion nonetheless satisfied the claim limitation of being “completely liquid.” The examiner noted that the primary reference described the hardstock fat as being “pumpable,” and stated that “[i]t is well understood that pumpable refers to the ability to move or transfer fluids or liquids.” The examiner took the position that the hardstock fat containing the crystallized portion “successfully meets the claimed limitation of the hardstock fat in liquid form [being] completely liquid.”

The Board disagreed with the examiner. The Board found it “unreasonable to interpret the term ‘completely liquid’ as encompassing hardstock fats that have already undergone some amount of crystallization. A liquid that has already undergone some amount of crystallization is not ‘completely’ liquid.” The Board found that such an “interpretation renders the word ‘completely’ a nullity, and such interpretations are disfavored.” Accordingly, the Board reversed the obviousness rejection.

Takeaway: U.S. examiners sometimes interpret the claims in a broader way than applicants intend. In such situations, it might be possible to argue that an examiner’s interpretation is unreasonably broad, and thus improper. Since examiners are likely to consider their interpretations to be reasonable, however, such arguments might require a supporting declaration from a skilled artisan, or an appeal to the PTAB.

Judges: Wilson, Kennedy, Gupta


September 10, 2021by Beau Burton1

In Ex parte Johnson, the Patent Trial and Appeal Board (“Board”) rejected an Examiner’s construction of a claim term because it conflicted with the meaning given in other patents from analogous art. 

The claims on appeal in Johnson were drawn to a prosthetic heart valve including, inter alia, a “cloth-covered undulating rod-like wireform.” Appellant’s specification defined the term “wireform” as “an elongated rod-like structure formed into a continuous shape defining a circumference around a flow orifice for supporting flexible leaflets in the various prosthetic valves herein.”  See US 2017/0239044, ¶ [0041]. 

In rejecting the claims as anticipated by US 5,928,281 (“Huynh”), the Examiner relied on element 99 of Huynh, which is shown below and linked here for convenience: 

Applying the broadest, reasonable interpretation and relying on a dictionary published in 2020, the Examiner found that element 99 of Huynh was a rod-like wireform because it had “an elongated structure with a shape similar to a stick, wand, staff, or the like.”  

Appellant disagreed with the Examiner’s construction, arguing element 99 of Huynh referred to a cloth top edge of a stent assembly rather than an “undulating rod-like wireform formed into a continuous shape having alternating cusps and commissures around a periphery.” Appellant’s argument was supported by Huynh’s description of element 99 as an “upper surface 99 (see FIG. 1) of [the] stent” and Huynh’s use of the term “wireform” elsewhere to refer to a “wire” or “wire-like” structure. Appellant’s construction was also consistent with the description of “wireform” in two separate analogous references to mean a bent “wire” structure (US 6,539,984 B2, issued Apr. 1, 2003) and a bent, machined, or molded “wire-like” structure (US 7,871,435 B2, issued Jan. 18, 2011).  

Rejecting the Examiner’s construction as unreasonably broad, the Board noted: 

It is well settled that prior art references may be indicative of what all those skilled in the art generally believe a certain term means . . . [and] can often help to demonstrate how a disputed term is used by those skilled in the art. Accordingly, the PTO’s interpretation of claim terms should not be so broad that it conflicts with the meaning given to identical terms in other patents from analogous art. 

Relevant to the Board’s decision were the contemporaneous patents and even the prior art relied on in the rejection, all of which were consistent with Appellant’s specification and construction.  

With Huynh lacking the claimed cloth-covered undulating rod-like wireform, the Board reversed the anticipation rejection.  

Takeaway: While it can be difficult to rebut an Examiner’s unreasonably broad construction of a claim term when the specification does not define, or does not sufficiently define, the claim term in question, valuable rebuttal evidence may be found in contemporaneous publications. As shown in Johnson, the Board found the consistent usage of the claim term in three analogous publications (including the allegedly anticipating reference) trumped the Examiner’s construction based on a generic dictionary definition. This is not to say dictionaries are always a poor source of evidence, but dictionaries typically include multiple definitions and a general definition may not accurately reflect how the claim term is used in the relevant art.  

JudgesS. Staicovici, E. Brown, W. Capp 


November 13, 2020by Richard Treanor

On November 9, 2020, the Patent Trial and Appeal Board issued a decision in Ex parte Tramontano et al. (Appeal 2020-002413) in which a misplaced claim interpretation/35 U.S.C. 112 argument distracted the Board from finding clear error in the Examiner’s obviousness rejection.

In Tramontano Claim 25, relating to the formation of a gel at a tissue treatment site, was the representative claim:

25. A process for forming a gel comprising:

forming an oxidized cellulose solution;

forming a precipitating composition; and

contacting the oxidized cellulose solution and the precipitating composition at a tissue treatment site thereby precipitating oxidized cellulose from the oxidized cellulose solution and forming the gel.

As explained in the Tramontano specification, the claimed gel may be used as an adhesive to seal tissue and/or to provide for the delivery of bioactive agents ([0274]).

During prosecution, the Examiner concluded that it would have been obvious to a person of ordinary skill in the art to substitute the cellulose ether used as the polymer in the cross-linked gels taught by Gehrke, with oxidized cellulose as taught by Blaskovich, at a tissue treatment site, as taught by Hubbard. In their Appeal Brief Appellants argued, among other things, that none of the cited references disclosed their claimed “precipitating composition” and, in response to a statement made by the Examiner in the Advisory Action (“it is not clear what the precipitation composition ….comprises”) argued to the Board that the lack of a 35 U.S.C. 112 rejection meant that the claim term “precipitation composition” was definite. Appellants further provided the Board with a legal framework for determining the meaning of a claim term, and argued that the references did not disclose the use of a “precipitating composition” as properly understood under their framework.

In affirming the rejection the Board first felt “obliged to make several initial points,” constituting over four full pages of their nine page analysis, the first of which was to correct Appellants’ legal framework for determining the meaning of a claim term, and the second of which was to apply the correct standard and find that the Blaskovich reference did indeed disclose the use of a “precipitating composition.” In coming to this conclusion and affirming the rejection, the Board characterized Appellants’ arguments regarding definiteness as “largely irrelevant” in view of the acknowledged fact that no 35 U.S.C. 112, second paragraph, rejection was at issue.

In Tramontano, the Board was clearly distracted (and perhaps irritated) by Appellants’ unnecessary arguments regarding definiteness to the point that Appellants’ other, stronger, arguments were ignored. In this regard, one of the applied references, Hubbard, was cited as teaching the delivery of oxidized cellulose, in gel form, to a tissue site. However, while Appellants argued that the combined references failed to suggest contacting an oxidized cellulose solution and a precipitating composition at a tissue treatment site, thereby forming the gel at the treatment site as claimed, this argument was not specifically addressed by the Board. Instead, the Board emphasized the presence of a “precipitating composition” and “oxidized cellulose solution” in the Gehrke and Blaskovich references.

Takeaways:  The Tramontano case illustrates the importance of leading with the best arguments and focusing the Appeal Brief on issues of clear error in the rejections of record. In addition, the Tramontano case provides us with a reminder to review claims for the presence of unnecessary steps, such as the “forming” steps in Claim 25 above. Such unnecessary steps can provide infringers with the possible defense of “divided infringement” if third parties perform certain steps within a claimed method.

25. (Amended) A process for forming a gel comprising:

forming an oxidized cellulose solution;

forming a precipitating composition; and

contacting the an oxidized cellulose solution and the a precipitating composition at a tissue treatment site thereby precipitating oxidized cellulose from the oxidized cellulose solution and forming the gel.

Judges: Prats, Katz, New