Document ID: s3://data.kl3m.ai/documents/govinfo/USCOURTS/USCOURTS-ca13-15-01194/USCOURTS-ca13-15-01194-0/pdf.json

Parties Involved:
Alfonso Cioffi
Appellant
Estate of Allen Frank Rozman
Appellant
Google, Inc.
Appellee

Document Text:

NOTE: This disposition is nonprecedential.

United States Court of Appeals 

for the Federal Circuit ______________________ 

ALFONSO CIOFFI, THE ESTATE OF ALLEN 

FRANK ROZMAN,

Plaintiffs-Appellants

v.

GOOGLE, INC.,

Defendant-Appellee

______________________ 

2015-1194

______________________ 

Appeal from the United States District Court for the 

Eastern District of Texas in No. 2:13-cv-00103-JRG-RSP, 

Judge J. Rodney Gilstrap.

______________________ 

Decided: November 17, 2015

______________________ 

ERIC W. BENISEK, Vasquez, Benisek & Lindgren, LLP, 

Lafayette, CA, argued for plaintiffs-appellants. Also 

represented by ROBERT MCARTHUR. 

STEPHANIE SKAFF, Farella Braun & Martel LLP, San 

Francisco, CA, argued for defendant-appellee. Also represented by EUGENE Y. MAR, ANDREW P. NGUYEN. 

______________________ 

Case: 15-1194 Document: 54-2 Page: 1 Filed: 11/17/2015
2 CIOFFI v. GOOGLE, INC. 

Before O’MALLEY, PLAGER, and BRYSON, Circuit 

Judges.

O’MALLEY, Circuit Judge. 

Alfonso Cioffi and The Estate of Allen Rozman (collectively “Appellants” or “Cioffi”) filed suit against Google, 

Inc. (“Appellee” or “Google”) on February 5, 2013 in the 

Eastern District of Texas alleging that the Google Chrome 

web browser (the “Accused Products”) infringed four 

reissue patents: U.S. Patent Nos. RE43,103 (the “’103 

patent”); RE43,500 (the “’500 patent”); RE43,528 (the 

“’528 patent”); and RE43,529 (the “’529 patent”). The 

district court construed several disputed terms of the four 

patents-at-issue. Based on these constructions, the 

district court held claim 21 of the ’103 patent to be invalid 

as indefinite, and the parties stipulated to noninfringement of all of the other asserted claims. 

On appeal, Cioffi challenges the construction of two 

terms: (1) “web browser process” and (2) “critical file.” 

Cioffi disputes the district court’s construction of the first 

term as erroneously requiring a “direct” access capability

and the second term as erroneously including “critical 

user files,” which renders the term indefinite. Because we 

agree that the district court erred in construing both of 

these terms, we reverse the district court’s claim construction and remand for further proceedings. 

I. BACKGROUND

A. The Reissue Patents

The four patents-at-issue are reissue patents originating from a patent issued as U.S. Patent No. 7,484,247 (the 

“’247 patent”) on January 27, 2009. That patent, entitled 

“System and Method For Protecting A Computer System 

From Malicious Software,” was directed to a way of protecting a computer from malware by segregating the 

suspected malware and directing it to execute and reveal 

itself in a safe, isolated part of the computer. In March 

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CIOFFI v. GOOGLE, INC. 3

2010, thirteen months after the ’247 patent issued, Cioffi 

surrendered the patent pursuant to 35 U.S.C. § 251 and 

sought reissue claims. The resulting four reissue patentsat-issue have the same abstract and, along with the ’247 

patent, share substantially identical specifications. 

The patents-at-issue describe computer processes, 

separated either logically or physically (using separate 

processors), into first and second browser processes. 

Potential malware downloaded from the Internet is 

directed to execute within the second browser process, but 

is not allowed to execute outside of the second browser 

process. Thus, the potential malware is insulated from 

and cannot damage any other aspect of the computer’s 

systems, including memory space accessible by the first 

browser process. 

Figure 1 of the ’528 patent (shown below) illustrates 

one preferred embodiment, involving two physically 

separate processors: (1) a first web browser process executed within first processor 120 with access to important 

files stored in first memory space 110, and (2) a second 

web browser process executed within second processor 

140 with access to its own expendable memory space 130. 

Untrusted content downloaded from the Internet is executed in the second web browser process running in 140, 

where it cannot damage important files stored in first 

memory space 110. 

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4 CIOFFI v. GOOGLE, INC. 

’528 patent fig. 1.

During prosecution, the examiner initially rejected all 

of the claims of the applications that ultimately issued as 

the ’500, ’528, and ’529 patents (“the ’500, ’528, and ’529 

patent applications”) under 35 U.S.C. § 102(b) in view of 

U.S. Patent Application No. 2002/0002673 (“Narin”). J.A. 

212-14. The examiner determined that Narin taught a 

method of operating a computer system with a first logical 

process capable of accessing data in a first memory space 

and a second logical process capable of accessing data in a 

second memory space. Id. The examiner found that the 

second logical process of Narin hosts non-secure software 

objects, and the data residing in the first memory space is

protected from corruption by malware downloaded from 

the network and operating as part of the second logical 

process. Id.

Cioffi responded with the argument that “Narin 

teaches away from the closed process [corresponding to 

the first browser process] being a browser process.” J.A. 

256. In other words, Cioffi argued that Narin is distinguishable from the claimed invention because Narin does 

not allow a browser program to be a part of the secure 

application, which Cioffi describes as a “first browser 

process.” 

On November 14, 2011, the examiner issued a Final 

Rejection Office Action maintaining its rejection of all the 

claims of the ’500, ’528, and ’529 patent applications. The, 

the examiner stated that: 

Despite the Applicant’s arguments that the 

claimed browser is a web browser, the specification . . . describe[s] the first logical process as being a video game and ‘including but not [being] 

limited to a word processor,’ respectively. According to the Applicant’s specification, the claimed 

first logical process or first browser process could 

include a web browser, such as Internet Explorer 

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CIOFFI v. GOOGLE, INC. 5

or Netscape; a video game; or a word processor. 

At the very least, the prior art’s disclosure reads 

on the Applicant’s video game and word processor 

interpretations of browser. . . . It is noted that features upon which applicant relies, such as the 

first browser process accessing Internet sites 

and/or data, are not recited in the rejected claims. 

Id. at 285-6 (¶¶6-8). 

In response, Cioffi amended all of the pending claims 

of the ’500, ’528, and ’529 patent applications to narrow 

the first and second “browser process” to the first and 

second “web browser process.” J.A. 798-810. Cioffi also 

added a limitation, “capable of accessing data of a website 

via the network,” to the first web browser process. J.A. 

314. Cioffi then explained, “Narin fails to disclose . . . a 

first web browser process capable of accessing data of a 

website via a network of one or more computers (e.g., the 

internet).” J.A. 332. The examiner allowed the claims. 

B. Procedural History 

On February 5, 2013, Cioffi filed suit against Google 

asserting infringement of the ’500, ’528, ’529, and ’103 

reissue patents by the Google Chrome web browser available for the Windows, Mac, Android, and Linux operating 

systems. The claims originally asserted were: 

’500 patent: claims 21, 23, 25, 29, 30, 31, 32, 37, 

38, 39, 41, 42, 43, 52, 66, 67 and 70. 

’528 patent: claims 1, 2, 5, 21, 23, 25, 30, 44, 46, 

52, 53, 55, 57, 58, 64, 65, 66, 67 and 70. 

’529 patent: claims 21, 23, 28, 30, 36, 38, 45, and

49. 

’103 patent: claim 21. 

Cioffi v. Google Inc., 2:13-cv-103, 2014 U.S. Dist. LEXIS 

123760, *8 (E.D. Tex. Aug. 28, 2014). Following a MarkCase: 15-1194 Document: 54-2 Page: 5 Filed: 11/17/2015
6 CIOFFI v. GOOGLE, INC. 

man hearing, the district court issued its Claim Construction Order on August 28, 2014. Id.

The district court adopted its preliminary construction of “web browser process” as a “process that can access 

data on websites.” Id. at *21. The court found that Cioffi

had distinguished Narin during patent prosecution by 

arguing that Narin discloses a “secure” or “closed” application that controls a separate process that runs an “open 

or untrusted application,” and that the “secure” application cannot be a web browser. Id. at *14-15. The court 

noted that, in response to the examiner’s rejection stating 

that the features relied upon to overcome Narin were not 

recited in the claims, Cioffi amended the claims to add 

“web” before “browser” and “capable of accessing data of a 

website via the network” before “first web browser process.” Id. at *17. The court found that the patentees 

relied on the added “web” limitation to overcome the 

examiner’s rejection, and “that reliance should be given 

effect by requiring that the ‘web browser process’ is capable of accessing data on websites.” Id. at *18-19. 

The district court then addressed a statement that 

Google made at the Markman hearing that it would agree 

to the court’s preliminary construction with an understanding that the claim term requires “direct” access to 

website data. While the court did not seek further briefing or argument on this issue, it did address it. The court 

stated that introducing the word “direct” would confuse 

rather than clarify the scope of the claims, but continued: 

To be clear, “can” in the Court’s construction does 

not mean “must” and instead refers to a capability. For this capability to be meaningful and consistent with the prosecution history, however, a 

“web browser process” must be capable of accessing a website without using another web browser 

process. In other words, although the Court’s construction does not preclude a web browser process 

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CIOFFI v. GOOGLE, INC. 7

from accessing websites by using another web 

browser process, a web browser process’s capability of accessing websites must not require using 

another web browser process.

Id. at *20-21 (emphasis in original). 

The district court also adopted its preliminary finding 

that the term “critical file” from the ’103 patent is indefinite, and held, therefore, that claim 21 of the ’103 patent

is invalid. The court found that references to “critical 

user files” found in the specification and prosecution 

history suggest that the term “critical file” includes critical “user” files. Id. at *60. It held that what is critical to 

a user is “entirely subjective,” and that “critical file,” 

therefore, fails to inform a person of skill in the art about 

the scope of the invention with reasonable certainty under 

Nautilus, Inc. v. Biosig Instruments, Inc., 134 S. Ct. 2120, 

2122 (2014). Id. at *61. 

The parties filed objections to aspects of the Claim 

Construction Order. Cioffi then served its Final Election 

of Asserted Claims, in which it narrowed the asserted 

claims to: 

’500 patent: claims 21, 30, 32, 39, 43, 66, and 70 

’528 patent: claims 5, 21, 23, 30, 44, 64, and 67 

’529 patent: claims 23, 30, 36, 38, 45, and 49 

See Final Judgment at 2-3, Cioffi, 2014 U.S. Dist. LEXIS 

123760 (2:13-cv-103), ECF No. 104. The district court 

overruled the parties’ objections. Order, Cioffi, 2014 U.S. 

Dist. LEXIS 123760 (2:13-cv-103), ECF No. 97. 

The parties then agreed that, based on the court’s 

claim constructions, Cioffi could not prevail on the issue of 

infringement. Cioffi’s First Amended Infringement Contentions had identified the browser kernel of the Accused 

Products as reading on the “first web browser process” of 

the asserted claims and the rendering engine of the 

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8 CIOFFI v. GOOGLE, INC. 

Accused Products as reading on the “second web browser 

process” of the asserted claims. The district court found 

that the rendering engine of the Accused Products “is not 

capable of and cannot access data of websites without 

using the browser kernel in the Accused Products,” and, 

therefore, the rendering engine cannot meet the “web 

browser process” limitation under the Claim Construction 

Order. Final Judgment at 2-3, Cioffi, 2014 U.S. Dist. 

LEXIS 123760 (2:13-cv-103), ECF No. 104. The district 

court entered a final judgment of non-infringement on 

December 2, 2014. Id.

Cioffi timely appealed the district court’s judgment, 

and we have jurisdiction under 28 U.S.C. § 1295(a)(1). 

II. DISCUSSION

Cioffi challenges the district court’s construction of 

two claim terms: (1) “web browser process” and (2) “critical file.” Claim construction is a matter of law, which we 

review de novo, but we review underlying factual findings 

by the district court for clear error. Teva Pharms. USA, 

Inc. v. Sandoz, Inc., 135 S. Ct. 831, 837-38 (2015). Generally, claim terms should be given their ordinary and 

customary meaning from the perspective of a person 

having ordinary skill in the art at the time of the effective 

date of the patent application. Phillips v. AWH Corp., 415 

F.3d 1303, 1312-13 (Fed. Cir. 2005) (en banc). To ascertain the scope and meaning of the asserted claims, we 

look to the words of the claims themselves, the specification, the prosecution history, and any relevant extrinsic 

evidence. Id. at 1315-17. This inquiry, at times, begins 

and ends with the intrinsic evidence. In fact, the specification is the single best guide to the meaning of the claim 

terms; it is often dispositive. Id. at 1318 (“[T]he specification ‘is always highly relevant to the claim construction

analysis. Usually, it is dispositive . . . .’”) (citation omitted). 

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CIOFFI v. GOOGLE, INC. 9

A. “Web Browser Process”

Cioffi argued in its opening brief on appeal that the 

district court erred by construing “web browser process”

at all, rather than maintaining the term’s plain and 

ordinary meaning. Appellant Br. 27. Cioffi has since 

conceded, however, that the district court’s construction of

“web browser process” as a “process that can access data 

on websites” is not reversible error.1 

Given this concession, the sole remaining dispute with 

respect to “web browser process” is whether the district 

court erred by reading into that limitation a “direct” 

access requirement. Under the district court’s construction, a “web browser process” does not have to access data 

on websites without using another “web browser process,” 

but “must be capable of accessing a website without using 

another web browser process.” Cioffi, 2014 U.S. Dist. 

LEXIS 123760 at *20-21 (emphasis added). Simply put,

the district court held that the “first web browser process” 

must be capable of accessing the Internet directly without 

the assistance of the “second web browser process,” and 

the “second web browser process” must be capable of 

accessing the Internet directly without the assistance of 

the “first web browser process.” 

1 See Appellant Reply Br. 2 (“Had the district court 

stopped with its preliminary construction of ‘web browser 

process’ to mean a ‘process that can access data on websites’ its error in deciding to construe the term would have 

been harmless . . . .”); Oral Argument at 1:20-2:03, available at http://oralarguments.cafc.uscourts.gov/default

.aspx?fl=2015-1194.mp3 (“what’s shown [at *21 of the 

Claim Construction Order] is the court’s definition that a 

‘web browser process’ is a ‘process that access data on 

websites.’ That definition, as a practical matter, is acceptable to us.”). 

 

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10 CIOFFI v. GOOGLE, INC. 

Claim construction starts with the claim language. 

Innova/Pure Water, Inc. v. Safari Water Filtration Sys., 

Inc., 381 F.3d 1111, 1116 (Fed. Cir. 2004). “Differences 

among claims can [ ] be a useful guide in understanding 

the meaning of particular claim terms.” Phillips, 415 

F.3d at 1314. “[T]he presence of a dependent claim that 

adds a particular limitation gives rise to a presumption 

that the limitation in question is not present in the independent claim.” Phillips, 415 F.3d at 1314-15 (citing 

Liebel-Flarsheim Co. v. Medrad, Inc., 358 F.3d 898, 910 

(Fed. Cir. 2004)).

Cioffi asserts that, under these claim differentiation 

principles, the term “web browser process” alone cannot 

be read to require a “direct” access capability. Cioffi first 

points to independent claim 21 of the ’528 patent, claiming it demonstrates that the “second web browser process” 

does not need to be capable of directly accessing data on 

websites without using another web browser. Claim 21 

states that the “first web browser process” needs to be 

“capable of passing data to the second web browser process.” ’528 patent col. 21 ll. 12-14. Thus, this claim 

implies that the “second web browser” can access data on 

websites indirectly with assistance from the “first web 

browser process.” Nothing in the language of claim 21 

requires that either the first or the second web browser 

process have direct access capability; instead, the claim 

requires only that the second process: (1) execute website 

data and (2) retrieve data that it executes. Id. In contrast, dependent claim 24 of the ’528 patent requires the 

“second web browser process” to be “capable of directly 

exchanging data with the network interface and with the 

first web browser process.” ’528 patent col. 21 ll. 26-30.2 

2 Claims 21 and 24 of the ‘528 patent are representative. In its Reply Brief and at oral argument, Cioffi 

clarifies that the same argument applies to claims 36 and 

 

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CIOFFI v. GOOGLE, INC. 11

Cioffi asserts that the “directly exchanging data with the 

network interface” limitation of claim 24 would be superfluous if claim 21 already required direct web access 

capability. 

According to Google, Cioffi’s claim differentiation argument fails because the court’s construction requiring 

that the web browser process have the capability to access 

data on a website directly does not render claims 21 and 

24 of the ’528 patent identical in scope. Claim differentiation principles do not apply here, according to Google, 

because claim 24 has two additional limitations as compared to claim 21. Dependent claim 24 not only adds a 

“directly exchanges data with the network interface” 

limitation, but also a “directly exchanges data with” “the 

first web browser process” limitation. Id. Thus, according 

to Google, only the first of these limitations would be 

subsumed by the court’s construction. 

We are not persuaded by Google’s arguments. If 

claim 21 already required a capability for “direct” access 

to the network, then the language of claim 24, which 

recites that the “second web browser process is capable of 

directly exchanging data with the network interface,” 

would be entirely duplicative. Thus, the language of the 

claims indicates that only in claim 24 does the second web 

browser have to have a “direct” access capability. While 

Google is correct that claim 24 adds another limitation 

compared to claim 21, that argument does not change the 

fact that the “directly exchanges data with a network” 

limitation would be rendered superfluous. See Mformation Techs., Inc. v. Research in Motion Ltd., 764 F.3d 

39 of the ’529 patent. See Appellant Reply Br. 5-7; Oral 

Argument at 3:23-3:59, available at http://oralarguments

.cafc.uscourts.gov/default.aspx?fl=2015-1194.mp3. The 

same argument also applies to claims 21 and 24 of the 

’500 patent. 

 

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12 CIOFFI v. GOOGLE, INC. 

1392, 1399 (Fed. Cir. 2014) (favoring a construction that 

does not render another limitation “superfluous”). Thus, 

we find Cioffi’s claim differentiation argument compelling

and find that the addition of the direct access capability 

limitation in claim 24 gives rise to a presumption that 

claim 21 lacks such a limitation. 

We do not find, moreover, that anything in the prosecution history overcomes the presumption created by 

these claim differentiation principles. Google argues that, 

during prosecution, Cioffi disclaimed a construction of 

“web browser process” that is broad enough to cover 

indirect access to website data in order to overcome 

anticipation by Narin. And Google is correct that, 

“[a]lthough claim differentiation is a useful analytic tool, 

it cannot enlarge the meaning of a claim beyond that 

which is supported by the patent documents, or relieve 

any claim of limitations imposed by the prosecution 

history. See, e.g., Retractable Techs., 653 F.3d at 1305 

(‘[A]ny presumption created by the doctrine of claim 

differentiation “will be overcome by a contrary construction dictated by the written description or prosecution 

history.”’).” Fenner Invs., Ltd. v. Cellco P’ship, 778 F.3d 

1320, 1327 (Fed. Cir. 2015). “The doctrine of prosecution 

disclaimer attaches where an applicant, whether by 

amendment or by argument, ‘unequivocally disavowed a 

certain meaning to obtain his patent.’” Schindler Elevator 

Corp. v. Otis Elevator Co., 593 F.3d 1275, 1285 (Fed. Cir. 

2010) (quoting Omega Eng'g, Inc. v. Raytek Corp., 334 

F.3d 1314, 1324 (Fed. Cir. 2003)). 

According to Google, Cioffi would not have been able 

to distinguish its claims from Narin if its “web browser 

process” was permitted to indirectly access data on websites through another browser process. Google contends 

that the examiner rejected Cioffi’s initial, unamended 

claim for a “browser process” because it would encompass 

prior art video games in which a renderer (i.e., the first 

process) relies on a second process to receive interactive 

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CIOFFI v. GOOGLE, INC. 13

network data. ’247 patent col. 14 ll. 28-45. Google argues 

that Cioffi thus surrendered indirect access to website 

data when it amended “browser process” to “web browser 

process” to exclude video game and word processing 

applications from the prior art. Appellee Br. 32. 

Cioffi responds that it never suggested in the course of 

amending “browser process” to “web browser process” that 

the “web browser process” must be capable of “directly” 

accessing website data without the assistance of another 

“web browser process.” Appellant Reply Br. 14. Instead, 

Cioffi says the key to overcoming Narin was not that the 

first “web browser process” could “directly” access website 

data, but, rather, was that the first “web browser process” 

could access website data at all. 

In Fenner, on which Google relies, we held that the 

patent’s specification and prosecution history narrowed 

the meaning of the term “personal identification number” 

beyond the construction proffered by the patentee notwithstanding the patentee’s claim differentiation argument. 778 F.3d at 1327. The patentee argued that

“personal identification number” should be construed 

broadly and could be associated with a particular user or 

a particular device. But the court held that the patentee 

could not walk away from what it had clearly stated 

during prosecution—that unlike the prior art, “[t]he 

present invention, on the other hand, is centered around 

the mobile user, not the mobile telephone. The user is 

identified by a personal code.” Id. at 1325. The patentee’s 

main argument on appeal was that the examiner did not 

rely on these statements, a point which we found to be 

irrelevant. Id. 

Unlike Fenner, the alleged disavowal of claim scope is 

far from unequivocal in Cioffi’s case. The prosecution 

history reveals that Cioffi distinguished Narin by arguing 

that its first browser process was not functionally equivalent to Narin’s “secure” or “trusted” application because 

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14 CIOFFI v. GOOGLE, INC. 

the first browser process of the reissue claims was capable 

of accessing untrusted data from websites, which would 

constitute “executable code from other sources that may 

not be trusted.” J.A. 256-57. The examiner recognized 

that Cioffi drew this distinction with Narin’s “secure” 

application, but nevertheless rejected Cioffi’s claims 

because “the features upon which applicant relies, such as 

the first browser process accessing Internet sites and/or 

data, are not recited in the rejected claims.” J.A. 286 (¶8). 

Rather, the examiner felt that the first logical process 

described in the specification was broad enough to encompass non-web browsers such as a “video game” and a 

“word processor.” Id. at ¶6. In response to this rejection, 

Cioffi amended its claims to explicitly state that the “first 

web browser” needed to be “capable of accessing data on 

websites.” J.A. 314, 332. 

Google refers to the following passage from the prosecution history, claiming that it shows that Cioffi disclaimed “indirect” access to website data by the first 

browser process in order to overcome Narin: 

As an example application 312 [the secure application in Narin] may provide some type of web 

browsing capability to its user, but rather than 

performing the actual web browsing functions itself, application 312 may call upon a generalpurpose browsing program to perform the web 

browsing.

J.A. 258, 590. See also Oral Argument at 18:01-19:18, 

available at http://oralarguments.cafc.uscourts.gov/defau

lt.aspx?fl=2015-1194.mp3. This passage simply confirms 

that the “secure” process of Narin cannot perform web 

browsing functions itself, but can call upon the “open” 

process to perform such functions. Nothing here suggests 

that the “secure” process thereby gains access to website 

data. Google further cites this passage:

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CIOFFI v. GOOGLE, INC. 15

Narin provides a technique for allowing an open 

or untrusted application to provide untrusted or 

open features for a secure application that are not 

directly implemented within the secure application (or closed application). In accordance therewith, an open or untrusted application is run in a 

separate auxiliary process from the closed or protected application. . . . The auxiliary process is 

started by the closed process; the closed process 

controls the lifetime of the auxiliary process and 

terminates it when the open features that it provides are no longer necessary. 

J.A. 588 (emphasis added). Google focuses on the phrase 

“not directly implemented,” but nothing contained in this 

passage clarifies that the “untrusted or open features” 

that the untrusted application provides the secure application include anything more than general web browsing 

capability, as opposed to website data. And even if such 

“features” included data from websites, nothing suggests 

that “are not directly implemented” equates to “are indirectly accessed.” In addition, the third sentence—stating 

that the untrusted process is started, controlled, and 

stopped by the “closed process”—also falls short of suggesting that the “closed process” thereby gains access to 

website data. Finally, the paragraph immediately following that passage affirmatively suggests that whatever the 

“untrusted features” provided to the “secure” application 

might include they cannot include “executable code from 

unknown sources”: 

Narin teaches away from the closed process [the 

first browser process] being a browser process. If 

the application is trusted, running a browser inproc may subvert the security scheme of the 

trusted application. If trust is to be maintained, 

executable code from unknown sources cannot be 

given access to the address space of the trusted 

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16 CIOFFI v. GOOGLE, INC. 

application and therefore cannot be run in process.

J.A. 256-57 (emphasis added). Thus, nothing from the 

prosecution history constitutes a clear and unmistakable

disavowal of “indirect” access. “There is no ‘clear and 

unmistakable’ disclaimer if a prosecution argument is 

subject to more than one reasonable interpretation, one of 

which is consistent with a proffered meaning of the disputed term.” Sandisk Corp. v. Memorex Prods., 415 F.3d 

1278, 1287 (Fed. Cir. 2005). Here, Cioffi has offered a 

reasonable alternative interpretation—that it differentiated Narin by explaining that its first web browser process, unlike Narin’s “secure” process, had access to 

website data. We find nothing in the prosecution history 

sufficient to overcome the presumption that “web browser 

process” alone does not have a “direct” access capability 

requirement. 

B. “Critical File”

We now turn to the dispute over the district court’s 

construction of “critical file” as including “critical user 

files,” which both parties agree would render the term 

indefinite under Nautilus, 134 S. Ct. at 2129. Under 

Nautilus, 35 U.S.C. § 112 ¶ 2 requires that “a patent’s 

claims, viewed in light of the specification and prosecution 

history, inform those skilled in the art about the scope of 

the invention with reasonable certainty.” Id. A claim 

“must be sufficiently definite to inform the public of the 

bounds of the protected invention, i.e., what subject 

matter is covered by the exclusive rights of the patent.” 

Ancora Techs., Inc. v. Apple, Inc., 744 F.3d 732, 737 (Fed. 

Cir. 2014) (quoting Halliburton Energy Servs., Inc. v. M-I 

LLC, 514 F.3d 1244, 1249 (Fed. Cir. 2008)). 

Google points out three references to “user” files in 

the specification of the ’247 patent: 

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CIOFFI v. GOOGLE, INC. 17

With the network interface program constrained 

in this way, malware programs are rendered unable to automatically corrupt critical system and 

user files located on the main memory storage area. 

. . . 

It is an object of the present invention to provide a 

computer system capable of preventing malware 

programs from automatically corrupting critical 

user and system files. 

. . . 

It is another object of the present invention to 

provide a user with an easy and comprehensive 

method of restoring critical system and user files 

that may have been corrupted by a malware infection.

’247 patent col. 7 ll. 8-11, 40-44, 53-56 (emphasis added). 

Google also points to the following references to “critical . . . user” files or data in the prosecution history:

Critical user data residing on the first electronic 

memory space is thereby protected from corruption by a malicious (malware) process downloaded 

from the network and executing on the second logical process.

. . . 

[M]alware programs are rendered unable to automatically corrupt critical system and user files

located on the main memory storage area.

J.A. 458-59 (emphasis added). 

The question is whether these five references to “user” 

files or data in the specification and prosecution history 

are sufficient to require that we read a “user files” limitation into the claim term “critical file.” On this point, our 

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18 CIOFFI v. GOOGLE, INC. 

recent decision in Ancora, 744 F.3d at 732, is instructive. 

Ancora states that “[a] claim term should be given its 

ordinary meaning in the pertinent context, unless the 

patentee has made clear its adoption of a different definition or otherwise disclaimed that meaning.” Id. at 734. 

There, we upheld the district court’s ruling that the terms

“volatile memory” and “non-volatile memory” were not 

indefinite because the parties did not dispute that there 

were “clear, settled, and objective” meanings for those 

terms in the art, and three “passing references” in the 

specification inconsistent with the established meanings 

were insufficient to overcome the clear ordinary meaning. 

Id. at 738.

In this case, the experts from both sides agreed that 

“critical file” had a well-understood and objective definition to one of skill in the art. Cioffi’s expert, Mr. H.E. 

(“Buster”) Dunsmore, stated that a person of skill would 

understand that a “‘critical file’ refers to files required for 

the proper operation of the computer’s systems.” Dunsmore Decl. ¶ 35, Exhibit 24 of Google’s Responsive Claim 

Construction Br., Cioffi, 2014 U.S. Dist. LEXIS 123760 

(2:13-cv-103), ECF No. 66 (“Dunsmore Decl.”). Similarly, 

Google’s expert, Dr. William A. Arbaugh, testified that, 

“[a] person of ordinary skill in the art knows that ‘system 

files’ are synonymous with ‘critical file’ and ‘critical system file.’” Arbaugh Decl. at 32, Exhibit 23 of Google’s 

Responsive Claim Construction Br., Cioffi, 2014 U.S. Dist. 

LEXIS 123760 (2:13-cv-103), ECF No. 66 (emphasis 

added) (“Arbaugh Decl.”).3

3 Based on this language, we disagree with Google’s 

characterization of Dr. Arbaugh’s testimony as explaining 

“that ‘system file’ can be a ‘critical file’ or a ‘critical system 

file,’ not that ‘critical file’ means ‘system file’ or only 

includes ‘system file.’” Appellee Br. 37.

 

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CIOFFI v. GOOGLE, INC. 19

The surrounding text of the experts’ declarations does

not alter this finding. The experts agreed that “critical 

user file” is entirely subjective. See Dunsmore Decl. ¶ 35 

(“users may disagree [sic] what is and is not critical to 

them); Arbaugh Decl. at 32 (“it is my opinion that a 

‘critical user file’ is entirely subjective because what is 

critical to one person may not be critical to another”). 

And the experts disagreed about whether “critical file” 

must be construed to include “critical user files” based on 

references to such files in the specification. See Dunsmore 

Decl. ¶ 35 (“One of skill would understand that a critical 

file would not be a user file”); Arbaugh Decl. at 33 (stating 

that, in light of the specification and prosecution history, 

a proposed construction of “critical file” that “does not 

include the concept of ‘critical user files’ . . . is underinclusive”). But neither party’s expert suggested that 

“critical file” alone is subjective or indefinite.

Our analysis thus shows that, without taking into 

consideration the few references to “user files” or “user 

data” in the intrinsic evidence, both sides’ experts agreed 

on an objective and well-understood meaning for “critical 

file.” Ancora teaches that, if there is a well-understood 

meaning for a term in the art, we do not allow a few 

inconsistent references in the specification to change this 

meaning. This is because, if the terms at issue have “so 

clear an ordinary meaning[,] a skilled artisan would not 

be looking for clarification in the specification.” Ancora, 

744 F.3d at 738. As in Ancora, “[t]here is no facial ambiguity or obscurity in the claim term,” and any ambiguity 

only arises from the specification. Id.

Google argues that, unlike Ancora, where the “passing 

references” inconsistent with the ordinary meaning were 

“perplexing,” here, Cioffi deliberately intended to protect 

critical user data and critical user files from malware as 

part of its invention. See id. While the specification 

references upon which Google relies do reference the 

advantage of protecting files with which a particular user 

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20 CIOFFI v. GOOGLE, INC. 

might be concerned, we see nothing that indicates that 

Cioffi intended its invention to do anything other than 

protect “critical files” as that concept is widely understood 

by those of skill in the art. We, thus, reject Google’s 

argument, and find that the few “passing references” to 

“user” files or data are insufficient to alter the wellunderstood, objective meaning of “critical file” agreed 

upon by the experts. We, therefore, reverse the district 

court’s holding that “critical file” in claim 21 of the ’103 

patent is indefinite. 

III. CONCLUSION

For the foregoing reasons, we find that that the district court incorrectly construed “web browser process” as 

requiring a “direct” access capability and incorrectly 

construed “critical file” as encompassing “critical user 

files.” We, therefore, reverse the district court’s claim 

constructions to the extent they are inconsistent with our 

findings and reverse the district court’s finding that the 

’103 patent is invalid as indefinite under 35 U.S.C. § 112

¶ 2. Because the parties stipulated to non-infringement 

based on the district court’s erroneous constructions, we

also remand for further findings pursuant to this opinion. 

REVERSED AND REMANDED 

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