An New (Old) Perspective on Claim Construction

In Century Electric Co. v. Westinghouse Electric & Mfg. Co., 191 F. 350 (8th Cir. 1911), the Eighth Circuit had in interesting perspective on claim construction. The Eighth Circuit said that a patent “is a contract made by the acceptance by the government of the offer which the patentee by his application makes to disclose his invention, in consideration that the United States will secure to him the exclusive use and sale of it for 17 years,”

The Court continued:

The offer embodied in the application becomes the specification of his patent, if his offer is accepted, and with his claims evidences the terms of the agreement. Such an agreement is interpreted by the same rules that determine other contracts. The court, should, as far as possible, place itself in the situation of the parties when they made their agreement and then seek to ascertain from the terms of their contract, in the light of the circumstances then surrounding them, what their intention was.

This intention should be deduced from the entire contract and not from any part of it or without any part of it, because they did not agree to it, or to any part of it, without every other part of it. The specification which forms a part of the same application as the claims must be read and interpreted with them, not for the purpose of limiting, or of contracting, or of expanding, the latter, but for the purpose of ascertaining from the entire agreement, of which each is a part, the actual intention of the parties and that intention when ascertained should prevail over the dry words and inapt expressions of the contract evidenced by the patent, its specification and claims.

Modern claim construction seem more rule-bound, and might be improved if animated by the purpose to determine what the inventor invented, not what the claims literally say.

Computer-Readable Recording Medium Is Not a Transitory Medium

In Sequoia Technology, LLC v. Dell, Inc., [2021-2263, 2021-2264, 2021-2265, 2021-2266] (April 12, 2022), the Federal Circuit disagreed with the district court’s claim construction for “computer-readable recording medium,” and thus reverses the district court’s ineligibility determination under 35 U.S.C. § 101. In addition, the Federal Circuit agreed with the district court’s claim construction for “disk partition” and “logical volume,” and thus affirmed the district court’s noninfringement determination.

The magistrate judge adopted and construed “computer-readable recording medium” to include transitory media (i.e., signals or waves),base upon the specification, which discusses “computer readable medium” as “including” a list of items—none of which are transitory— and interpreted that language as leaving the door open for media that could be transitory.

The Federal Circuit noted at the outset that the claim language does not actually recite a “computer-readable medium” or CRM. Instead, it more narrowly recites “computer-readable recording medium storing instructions. The Court said that a person of ordinary skill would not understand transitory signals, such as carrier waves, to record or store instructions in memory systems. This is because transitory signals, by their very nature, are fleeting and do not persist over time. Other elements in the claim confirm that the claim is directed to hardware as opposed to transitory waves or signals.  The Federal Circuit found that the claim language demonstrates that claim 8 is not directed to a transient signal, but rather to a non-transient storage medium.

The Federal Circuit then turned to the specification, which discloses only non-transitory media.  The Court said the use of a term denoting a nonexhaustive list does not eviscerate our obligation to construe terms in the context of the entire patent. The context

here makes clear that the term “computer-readable recording medium” cannot encompass transitory media.

The Federal Circuit declared that its decision rests solely on the intrinsic evidence, and that it was unpersuaded by arguments to the contrary, which rest on extrinsic evidence.  The Court further noted that not only was this extrinsic evidence was inconsistent with the intrinsic evidence and also based on different express definitions of CRM in patent specifications directed to different inventions.

The Federal Circuit disagreed with the district court’s claim construction and, consequently, reversed the district court’s holding that claims 8–10 are ineligible under § 101.

How Many?

An often critical issue in determining patent infringement is how many of a specified claim element are required by the claim. This issue can arise in a variety of ways:

A or An

The general rule is that “a” or “an” means one or more. In KCJ Corp. v. Kinetic Concepts, Inc., 223 F.3d 1351 (Fed. Cir. 2000), the Federal Circuit observed:

an indefinite article “a” or “an” in patent parlance carries the meaning of “one or more” in open-ended claims containing the transitional phrase “comprising.” … Unless the claim is specific as to the number of elements, the article “a” receives a singular interpretation only in rare circumstances when the patentee evinces a clear intent to so limit the article. … Under this conventional rule, the claim limitation “a,” without more, requires at least one.

See, also  Baldwin Graphic Sys., Inc. v. Siebert, Inc., 512 F.3d 1338 (Fed. Cir. 2008).

However, the Federal Circuit indicated that there are situations where “a” or “an” can mean “only one.” See, for example, Harari v. Lee, 656 F.3d 1331 (Fed. Cir. 2011), and Insituform Techs., Inc. v. CAT Contr., Inc., 99 F.3d 1098, 1106 (Fed. Cir. 1996).

How can the careful prosecutor ensure the interpretation he or she wants? One way is to provide a definition in the specification. Thousands of patents do.

  1.  As used herein, “a” or “an” or “the” can mean one or more than one. For example, “a” widget can mean one widget or a plurality of widgets. See, e.g., U.S. Patent No. 1082263.9
  2. As used herein, “a” or “an” may mean one or more than one. See, e.g., U.S. Patent No. 10525082.
  3. Unless otherwise indicated or the context suggests otherwise, as used herein, “a” or “an” means “at least one” or “one or more.” See, e.g., U.S. Patent No. 10546223.
  4.  As used herein, “a” or “an” means “at least one” or “one or more” unless otherwise indicated. See, e.g., U.S. Patent No.7465758.
  5. As used herein, “a” or “an” means at least one, unless clearly indicated otherwise. See, e.g., U.S. Patent No.11275080.
  6. As used herein, “a” or “an” means one or more unless otherwise specified. See, e.g., U.S. Patent No. 9540312.

A problem with definitions is that the prosecutor has to commit to a meaning, and do so by the time of filing. In the examples above definitions #1 and #2 aren’t really definitions at all – they merely state a possible meaning. No options are foreclosed, buy no certainty is achieved. Definitions #3 expresses a preference, but there is still some uncertainty. Definitions #4 – #6 provides a definition that is only superseded by an “indication” or a “specification” otherwise.

More certainty is obtained by specifying “one” or “at least one” when the element is described and claimed.


The simple word “or” has multiple, inconsistent meanings. In some contexts, “or” can express exclusive alternatives. In these cases “A or B” means either A and not B, or B and not A. See, Kustom Signals, Inc. v. Applied Concepts, 264 F.3d. 1326 (Fed. Cir. 2001). In other contexts, “or” can express non-exclusive alternatives. In these cases “A or B” means just A, A and B, or just B. Brown v. 3M, 265 F.3d 1349 (Fed. Cir. 2001).

As discussed above, definitions can help provide some certainty. There are numerous examples:

  1. The term “or” as used in this disclosure is to be understood to refer a logically inclusive or not a logically exclusive or, where for example the logical phrase (if A or B) is satisfied when A is present, when B is present or where both A and B are present (contrary to the logically exclusive or where when A and B are present the if statement is not satisfied). See, e.g., U.S. Patent No. 9747910.
  2. As used herein, “or” is understood to mean “inclusively or,” i.e., the inclusion of at least one, but including more than one, of a number or list of elements. In contrast, the term “exclusively or” refers to the inclusion of exactly one element of a number or list of elements. See, e.g., U.S. Patent No. 10639598.

The examples above provide definitions of an inclusive “or,” but also provide a template of how to define an exclusive “or.”

Alternatively, the careful prosecutor can be more precise in the specification and claims. One way is to claim “A and/or B” for an inclusive “or”, and “either A or B” for an exclusive “or.”


“And” has also caused problems for patent owners.  In Super Guide Corp. v. DirecTV Enters., Inc., 358 F.3d 870, 885-86 (Fed. Cir. 2004), the patent owner and the accused infringer disagreed over the effect of “and” in the claim limitation “first means for storing at least one of a desired program start time, a desired program end time, a desired program service, and a desired program type.” The patent owner argued that this language required at least one of any of the four list categories. The accused infringer argued that this language required at least one from each of the four listed categories. The Federal Circuit agreed with the accused infringer, noting that the phrase “at least one of” preceded a series of categories of criteria, and the patentee used the term “and” to separate the categories of criteria, which connotes a conjunctive list. The Federal Circuit cited William Strunk, Jr. & E.B. White, The Elements of Style 27 (4th ed. 2000). The TTAB has reached a similar result in Ex Parte Jung, Appeal 2016-008290 at 2 (P.T.A.B. Mar. 22, 2017).

Thus when enumerating a list, the careful prosecutor must be mindful choosing whether to join the list with “and” or “or”


If “or” and “and” can cause problems, it would seem that “and/or” can likewise cause problems. As Wikipedia notes, “and/or” has come under criticism in the courts. Judges have called it a “freakish fad”, an “accuracy-destroying symbol”, and “meaningless”. In Ex Parte Gross, Application No. 11/565,411, the Examiner rejected claim 1 as indefinite based upon the use of “and/or.” However, the PTAB reversed – finding that “A and/or B” does have a meaning and that meaning is A alone, B alone, or A and B together. The Board noted the “preferred verbiage” should be more simply “at least one of A and B.”

While not popular with legal purists, “and/or” may be the best choice to get the intended claim scope.

“A Processor” Can Mean More Than One Processor, But At Least One of Multiple Processors Has to be Capable of Performing All of “Said” Processor’s Functions

In Salazar v. AT&T Mobility LLC, [2021-2320, 2021-2376] (April 5, 2023), the Federal Circuit affirmed judgment of noninfringement of U.S. Patent No. 5,802,467 describing technology for wireless and wired communications.

Claim 1 of the ‘467 patent required “a microprocessor for generating a plurality of control signals used to operate said system, said microprocessor creating a plurality of reprogrammable communication protocols, for transmission to said external devices wherein each communication protocol includes a command code set that defines the signals that are employed to communicate with each one of said external devices.”  The district court construed the court construed “a microprocessor” to mean one microprocessor.”

On appeal, Salazar argued that the court should have interpreted a microprocessor” to require one or more microprocessors, any one of which may be capable of performing each of the “generating,” “creating,” and “retrieving” functions recited in the claims.

The Federal Circuit explained that the indefinite article “a” means “‘one or more’ in open-ended claims containing the transitional phrase ‘comprising.’” The Court said an exception to the general rule that “a”  means more than one only arises where the language of the claims themselves, the specification, or the prosecution history necessitate a departure from the rule.”   The Federal Circuit further explained that the use of the term “said” indicates that this portion of the claim limitation is a reference back to the previously claimed” term.  The claim term “said” is an “anaphoric phrase, referring to the initial antecedent phrase”. The subsequent use of the definite article ‘said’ in a claim to refer back to the same claim term does not change the general plural rule, but simply reinvokes that non-singular meaning.”

The Federal Circuit reviewed prior cases interpreting “a” and noted in particular In re Varma, 816

F.3d 1352 (Fed. Cir. 2016), which the district court had explained that the claim term provided certain functions that the “said microprocessor” must be “necessarily configured to perform as well as the structural relationship between ‘said microprocessor’ and other structural elements.”  Thus, the district court reasoned, “at least one microprocessor must satisfy all the functional (and relational) limitations recited for ‘said microprocessor.’ On appeal, Salazar’s argued that a correct claim construction would encompass one microprocessor capable of performing one claimed function and another microprocessor capable of performing a different claimed function, even if no one microprocessor could perform all of the recited functions.  The Federal Circuit rejected this argument, agreeing with the district court that while the claim term “a microprocessor” does not require there be only one microprocessor, the subsequent limitations referring back to “said microprocessor” require that at least one microprocessor be capable of performing each of the claimed functions, which the Court said was “entirely consistent” with it precedents. The Court noted that, as it stated in Varma, for a dog owner to have a dog that rolls over and fetches sticks, it does not suffice that he have two dogs, each able to perform just one of the tasks.

The Canons of Claim Construction Showed that the District Court was Half Right and Half Wrong

In SSI Technologies, LLC v, Dongguan Zhengyang Electronic Mechanical Ltd., [2021-2345, 2022-1039] (February 13, 2023) the Federal Circuit affirmed in part, reversed in part, vacated in part, and remanded the district court’s grant of summary judgment to DZEM on SSI’s infringement
claims, dismissal of DZEM’s invalidity counterclaims, and granted summary judgment to SSI on the tortious interference counterclaim.

SSI has asserted U.S. Patent Nos. 8,733,153 and 9,535,038, generally directed to sensors for determining the characteristics of fluid in a container, such as a fuel tank.against DZEM. this case.

The dispute in the district court regarding the ’153 patent turned mainly on the limitation in claim 1 that recites a controller configured to determine whether a contaminant exists in the
fluid based on the temperature of the fluid, a time period from when the sound wave is produced to when the echo is detected, and at least one of the group of a) whether a measured volume is out of range and b) a dilution of the fluid is detected while the measured volume of the fluid decreases. The district court construed the second item of the Markush group in that limitation, “a dilution of the fluid is detected while the measured volume of the fluid decreases,” to require that the contaminant determination actually consider the measured volume of the fluid. This construction was based upon the district court’s determination that amendments to the claim during prosecution was designed to incorporate the error-detection capability recited in the specification.

The Federal Circuit agreed with the district court, noting that the language “measured volume” in the claim requires that the volume of the liquid in the tank must be determined and considered as part of the contamination analysis recited in claim 1. The Court pointed out that a claim construction that gives meaning to all the terms of the claim is preferred over
one that does not do so. Thus the Federal Circuit affirmed summary judgment of non-infringement as to the ‘153 patent.

With respect to the ’038 patent, the dispute in the district court turned mainly on the district court’s construction of the term “filter” and its application of that construction in its infringement analysis. The district court adopted DZEM’s proposed construction of “filter,”
construing the term to mean “a porous structure defining openings, and configured to remove impurities larger than said openings from a liquid or gas passing through the
structure.” Since the DZEM device had a non-porous cover, the court found no infringement.

The Federal Circuit disagreed with the district court construction of filter. The Court said that the specification of the ’038 patent contains no requirement regarding the size of the filter openings. The Federal Circuit conceded that each embodiment disclosed in the ’038 patent contains a mesh filter, which has very small openings, but stated that the scope of a claim is not ordinarily limited to preferred embodiments or specific examples in the specification. The Court said that while the specific embodiments of the filters disclosed in the ’038 patent specification contain small holes, the general references to a “filter” in the specification are quite broad and do not reflect an intent to limit the term “filter” to the disclosed embodiments. In particular the reference to use of the mesh was limited to “some embodiments.” The Federal Circuit concluded that as long as the openings in the filter are small enough to prevent at least some gas bubbles from entering the sensing area, the openings need
not be smaller than any particular maximum size.

In light of this construction, the Federal Circuit vacated the grant of summary judgment of the ‘038 patent in its entirety, and remanded for further proceedings.

On the grant of summary judgment to SSI on DZEM’s tortious interference
counterclaim, the Federal Circuit said that in order to assert a claim “that a patent
holder has engaged in wrongful conduct by asserting claims of patent infringement,” the plaintiff “must establish that the claims of infringement were objectively baseless.” The Federal Circuit said that the district court held that SSI’s infringement claims were not objectively baseless, and that it discerned no error in that conclusion, pointing to SSI’s expert report regarding infringement as evidence that the suit was not objectively baseless. The Court said that the existence of an expert opinion can be evidence that a party’s position is not unreasonable, even if there is conflicting expert testimony in the record. DZEM was required to establish by clear and convincing evidence that SSI’s infringement suit was objectively baseless, but it failed to introduce any evidence of objective baselessness. Thus, the Federal Circuit affirmed the district court’s grant of summary
judgment to SSI on the tortious interference counterclaim.

The Inventor’s Lexicography Governs

In Grace Instrument Industries, LLC v. Chandler Instruments Company, LLC, [2021-2370] (January 12, 2023), the Federal Circuit vacated the district court’s finding that the claims of U.S. Patent No. 7,412,877 were indefinite.

The ‘877 patent relates to a viscometer for measuring the viscosity of drilling fluid. The discometer uses a “enlarged” chamber located between a lower chamber, housing the sample fluid, and a pressurization fluid inlet, located in the top section of the viscometer’s
pressure vessel. This enlarged chamber is large enough such that the level of the sample fluid, which before pressurization initially fills both the lower chamber and the enlarged chamber, never falls below the transition point between the lower chamber and enlarged chamber when the application of the pressurization fluid compresses the sample fluid.

1. A pressurized device comprising:
(a) a pressure vessel within which is vertically disposed at least one top section filled
with a pressurization fluid of a first density and at least one lower section filled with a test sample of a second density,
(b) an enlarged chamber with reduced openings positioned between the at least one top section and the at least one bottom section for communicating pressure with said top section and said lower section within said pressure vessel,
(c) whereby said pressurization fluid would not mix with said test sample because of the nature of their density difference.

The district court determined that the term “enlarged chamber” as used in the claims was indefinite, making the asserted claims of the ‘877 patent invalid. The district court explained that “enlarged” is a “term of degree” that “necessarily calls for some comparison against
some baseline.” Finding that the ’877 patent “does not provide the requisite objective boundaries” for a skilled artisan, the district court held that “enlarged chamber” is indefinite.

The Federal Circuit said that a patent is invalid for indefiniteness if its claims, read in light of the specification delineating the patent, and the prosecution history, fail to inform, with reasonable certainty, those skilled in the art about the scope of the invention.” The ultimate conclusion that a claim is indefinite under 35 U.S.C. § 112, ¶ 2 is a legal conclusion, which we review de novo.

Grace argued before the district court that the term “enlarged chamber” should be construed as “the area between reduced openings that is large enough to hold excess test sample (i.e., the type of fluid normally used in these machines) to prevent mixing of pressurization fluid and test sample below the bottom fin during elevated pressurization.” The district court declined to adopt that construction, concluding that the ’877 patent fails to disclose objective
boundaries for a skilled artisan to know what the claimed “enlarged chamber” must be larger than. The Federal Circuit said that this was error.

The Federal Circuit said that the intrinsic record informs a skilled artisan that the ’877 patent and its claims are directed to a viscometer with an “enlarged chamber” that is large enough to prevent pressurization fluid from entering the lower section of the pressure vessel—where the viscosity of the test sample is being measured—during elevated pressurization. In other words, the enlarged chamber has to be able to contain enough sample fluid at the pre-pressurization stage such that, during pressurization, the sample fluid level does not fall below the bottom of the enlarged chamber and into the viscometer’s lower, testing section. Although “enlarged chamber” is not a term of art, the intrinsic record sufficiently guides a skilled artisan to the meaning of that term as used in the ’877 patent. Where the specification instructs as to the meaning of a claim term, “the inventor’s lexicography governs.”

The Federal Circuit concluded that the term “enlarged chamber” in the ’877 patent meant “a chamber that is large enough to contain excess test sample prior to pressurization to prevent mixing of the test sample and pressurization fluid in the lower measurement zone when the test sample is pressurized to maximum rated pressure.” The Court thus vacated the district court’s determination that “enlarged chamber” is indefinite, vacatef the district court’s invalidity determinations based thereon, and remanded for further proceedings
consistent with this opinion.

“AND” Can Mean “OR” Depending on the Context

In Kaufman v. Microsoft Corp., [2021-1634, 2021-1691] (May 20, 2022) the Federal Circuit affirmed the district court’s denial of Microsoft’s post-judgment challenges to a $7 million damage award for infringement of U.S. Patent No. 7,885,981, and reversed the district court’s denial of prejudgment interest.

The ’981 patent addresses the creation of user interfaces that permit users to interact with data in relational databases. One of the issues was whether the claim required the automatic generation of an end user interface. The word automatic did not appear on the body of the claim, but the preamble stated that the method involved a “processor for automatically generating and end-user interface.”

Microsoft moved for summary judgment, arguing that that the phrase “automatically
generating” found in the preamble of claim 1 is limiting, and means that “no human labor required,” and thus Microsoft product does not infringe. Microsoft argued that the district court erred in failing to clarify the reach of the “automatically” requirement for the jury, warranting a new trial under O2 Micro because a clarification could reasonably have led the jury to a different verdict. However, the Federal Circuit held that Microsoft failed to preserve its O2 Micro challenge.

The Federal Circuit noted that in the original Markman proceeding, the parties did
not request a construction of the word “automatically” or raise an issue of the scope of the “automatically generating” requirement. During the motion for summary judgment
briefing, Microsoft described the “human labor” involved in use of Dynamic Data, and it
asserted a need for a claim construction under O2 Micro, but it said only that there was “a fundamental legal dispute as to the meaning of “automatic” in the claims, it never clearly said that, apart from what “automatic” means, a construction was needed specifying what functions had to be automatic, i.e., the scope of the “automatically generating” requirement. Further, Microsoft never offered the district court a formulation of such a claim construction resolving that scope issue, including at the at the pre-trial hearing.

The Federal Circuit also rejected Microsoft’s argument, presented for the first time on appeal, that “automatically generating” should be construed broadly to require some defined set of steps beyond those recited by the claims in (a), (b), and (c) to be performed automatically. Microsoft never proposed such a construction to the district court.

Microsoft’s final argument was that there was insufficient evidence to support the jury’s finding infringement, but the Federal Circuit agreed with the district court correctly explained, the jury reasonably that the manual step identified by Microsoft were not part of the claim requirement that were required to be performed automatically.

Finding that Microsoft failed to establish that the district court erred in its claim construction or that the jury’s verdict was not supported by substantial evidence, the Federal Circuit affirmed the jury’s finding that the accused processes come within the “automatically generating” limitation.

Microsoft also argued that the district court erred in the post-trial ruling when it concluded that “and” means “and/or,” contending that the phrase should be given the conjunctive
meaning, so that the client application (constituting the end-user interface) must integrate into each of the individual mode displays (for creating, retrieving, updating, and deleting) all three of the “processes for representing, navigating, and managing said relationships across tables.” The Federal Circuit agreed with the district court’s construction, noting that a claim construction that excludes a preferred embodiment is rarely, if ever correct and would require highly persuasive evidentiary support. The Federal Circuit noted that in the sole embodiment in the patent, a “retrieve” display lacks a “managing” process. The the Federal Circuit said that “and” must be construed as “and/or” so that the claim would cover the only disclosed embodiment.

The Federal Circuit recognized that it cannot redraft claims whether to make them operable or to sustain their validity, or to cause them to encompass the sole described embodiment, it said that that is not what it was doing here. The Court said where there is “only one reasonable construction,” it has recognized that, in certain contexts, the word “and” can reasonably be understood to denote alternatives, rather than conjunctive requirements.

Finally, the Federal Circuit addressed the denial of prejudgment interest. The district court provided two rationales for denying prejudgment interest to Kaufman: first, that the jury
verdict “subsumed interest,” and second, that Mr. Kaufman was responsible for “undue delay” in bringing the lawsuit, causing prejudice to Microsoft. The Federal Circuit said that the jury verdict cannot reasonably be understood to include interest, noting there was no testimony about how the interest would be calculated. The Federal Circuit also said that the district court also erred in finding Kaufman was responsible for undue delay justifying the denial of prejudgment interest. The Federal Circuit said that the fact that Mr. Kaufman
did not sue for five years after he became aware of Microsoft’s potential infringement does not alone justify a finding of undue delay. The Federal Circuit said that Microsoft presented
no evidence as to why Kaufman’s delay was undue.

An Affirmative Claim Construction is not Always Needed, But it was Here

In Sound View Innovations, Inc., v. Hulu, LLC, [2021-1998] (May 11, 2022), the Federal Circuit, whille agreeing with the district court’s claim construction, the Federal Circuit disagreed with the district court’s application of that construction, so it vacated summary judgment of no infringement of U.S. Patent No. 6,708,213 on a “Method for Streaming Multimedia Information over Public Networks.”

Sound View alleged that, under Hulu’s direction, when an edge server receives a client request for a video not already fully in the edge server’s possession, and obtains segments of the video seriatim from the content server (or another edge server), the edge server transmits to the Hulu client a segment it has obtained while concurrently retrieving a remaining segment. The claim at issue specifies a method, involving a content server and intermediate servers (helper servers), to use when a client requests a streaming multimedia (SM) object.

The district court construed the limitation to require that the same buffer in the helper
server—host both the portion sent to the client and a remaining portion retrieved
concurrently from the content server or other helper server. With that claim construction, Hulu sought and obtained summary judgment of non-infringement, arguing that it was undisputed that, in the edge servers of its content delivery networks, no single buffer hosts both the video portion downloaded to the client and the retrieved additional portion. Sound View argued, in response, that there remained a factual dispute about whether “caches” in
the edge servers met the concurrency limitation as construed. The district court held, however, that a “cache” could not be the “buffer” that its construction of the downloading/
retrieving limitation required, and on that basis, it granted summary judgment of non-infringement.

The Federal Circuit citing theapplicant’s statements in the prosecution history, affirm the district court’s construction of the downloading/retrieving limitation, but rejected the district court’s determination that “buffer” cannot cover “a cache,” and therefore vacated the district court’s grant of summary judgment and remanded for further proceedings.

The Federal Circuit noted that all the district court did in construing “buffer” was to declare that it must exclude a “cache.” It said that the district court did not adopt an affirmative construction of what constitutes a “buffer” in the patent. Although there is no per se rule against negative constructions, which in some cases can be enough to resolve the relevant dispute, the Federal Circuit found the court’s construction was inadequate for the second step of an infringement analysis—comparison to the accused products or methods.

The Federal Circuit said that the district court did not decide, and the record does not establish, that “cache” is a term of such uniform meaning in the art that its meaning in the patent must be relevantly identical to its meaning when used by those who labeled the pertinent components of the accused edge servers. In the absence of such a uniformity-of-meaning determination, the district court’s conclusion that the patent distinguishes its buffers and caches is insufficient to support a determination that the accused-component “caches” are outside the “buffers” of the patent. The Federal Circuit said that what was needed was an affirmative construction of “buffer”— which could then be compared to the accused-component “caches” based on more than a mere name, and the district
court did not supply the needed construction.

The Federal Circuit noted an additional reason why an affirmative construction was needed: even in the patent the terms “buffer” and “cache” did not appear to be mutually exclusive,
but instead seem to have at least some overlap in their coverage.

Ordinary Meaning Can Be Broader than Disclosed Embodiments

In Evolusion Concepts, Inc. v. HOC Events, Inc., [2021-1963] (January 14, 2022) the Federal Circuit reversed the grant of summary judgment of non-infringement of U.S. Patent No. 8,756,845 on a “Method and Device for Converting Firearm with Detachable Magazine to a Firearm with Fixed Magazine,” , reversed the denial of summary judgment of direct infringement as to the independent claims 1 and 8, and remanded for further proceedings.

The district court held that the term “magazine catch bar” in the asserted claims of the ’845 patent excludes a factory installed magazine catch bar. Claim 15 requires removing “the factory installed magazine catch bar” and then installing “a magazine catch bar.” From this, the district the court concluded that the magazine catch bar that is installed must be “separate and distinct from the factory-installed magazine catch bar”; otherwise, “factory-installed” would be superfluous. Because a term that appears in multiple claims should be given the same meaning in all those claims, the court held that the term “magazine catch bar” in claims 1 and 8 similarly must exclude a factory-installed magazine catch bar. This claim construction precluded literal infringement because Juggernaut’s products use the factory-installed magazine catch bar. The court also determined that Juggernaut does not infringe under the doctrine of equivalents.

The Federal Circuit noted that the principle that the same phrase in different claims of the same patent should have the same meaning is a strong one, overcome only if it is clear that the same phrase has different meanings in different claims. The Federal Circuit noted that while claim 15 was directed to a method, claims 1 and 8 claimed a firearm and a device, respectively. The Federal Circuit said that nothing in the language of claims 1 and 8 limits the scope of the generic term “magazine catch bar” to exclude one that was factory installed—specifically, as Juggernaut asserts, factory installed as part of an original
firearm with a detachable magazine.

The Federal Circuit said that Juggernaut was correct that the meaning of the term in claims 1 and 8 could well be informed by a meaning of the term made sufficiently clear in claim 15, but Juggernaut was incorrect that the use of “magazine catch bar” in claim 15 narrows the meaning of the term to support the
urged exclusion of factory-installed magazine catch bars. The Federal Circuit agreed that claim 15 required removing a factory installed magazine catch but it did not require discarding that catch bar, or installing a different catch bar. The Federal Circuit concluded that the specification supports the ordinary-meaning interpretation of “magazine catch bar.” The Federal Circuit said the specification nowhere limits the scope of a “magazine catch bar” to exclude factory-installed ones from the assembly that achieves the fixed-magazine goal.

Juggernaut argued that the disclosed embodiments do not illustrate OEM magazine catch bars, but the Federal Circuit said that cannot make a difference in this case. The Federal Circuit has repeatedly held that “it is not enough that the only embodiments, or all of the embodiments, contain a particular limitation to limit claims beyond their plain meaning.” The Federal Circuit thus construe the term “magazine catch bar” according to its ordinary meaning, which includes a factory installed magazine catch bar.

The Proper Claim Construction of a Term is Not Necessarily the Sum of its Parts

In Intel Corp. v. Qualcomm Inc., [2020-1664] (December 28, 2021), the Federal Circuit affirmed the final written decision of the originally challenged claims of U.S. Patent No. 8,229,043, but vacated and remanded as to the substitute claims.

The Federal Circuit addressed first considered the phrase “radio frequency input signal” in ’043 patent claims 17, 19, and 21. Intel argued that the term should be given its ordinary meaning, while Qualcomm argued for a more specific construction. The Federal Circuit noted that ‘[e]ven without considering the surrounding claim language or the rest of the patent document, . . .it is not always appropriate to break down a phrase and give it an interpretation that is merely the sum of its parts.” The Federal Circuit said that the surrounding language points in favor of Qualcomm’s construction, adopted by the Board. The Federal Circuit said the linguistic clues suggested that “radio frequency input signal,” to the relevant audience, refers to the signal entering the device as a whole, not (as Intel proposes) to any radio frequency signal entering any component. The Federal Circuit said that the specification provides further support for the Board’s reading.

The Federal Circuit concluded that in sum, while Intel’s interpretation may have superficial appeal, Qualcomm’s better reflects the usage of “radio frequency input signal” in the intrinsic record, and affirmed it.

On the question of obviousness, the Federal Circuit concluded that substantial evidence does not
support the Board’s determination that a skilled artisan would have lacked reason to combine the prior art to achieve substitute claims 27, 28, and 31. The Federal Circuit rejected the Board’s rationale for determining that it would not have been obvious to combine the references. The Federal Circuit noted that a rationale is not inherently suspect merely because it’s generic in the sense of having broad applicability or appeal.