NOTE: This disposition is nonprecedential.

 

United States Court of Appeals 

for the Federal Circuit ______________________ 

UNITED ACCESS TECHNOLOGIES, LLC,

Plaintiff-Appellant

v.

AT&T CORP., AT&T SERVICES, INC., SBC 

INTERNET SERVICES, INC., CENTURYTEL 

BROADBAND SERVICES LLC, QWEST 

CORPORATION,

Defendants-Appellees

______________________ 

2021-2002, 2021-2007

______________________ 

Appeals from the United States District Court for the 

District of Delaware in Nos. 1:11-cv-00338-KAJ, 1:11-cv00339-KAJ, Circuit Judge Kent A. Jordan.

______________________ 

Decided: April 15, 2022 

______________________ 

ANTHONY MATTHEW GARZA, Charhon, Callahan, Robson, & Garza PLLC, Dallas, TX, argued for plaintiff-appellant. Also represented by STEVEN CHASE CALLAHAN, BRETT 

CHARHON. 

 MICHAEL HAWES, Baker Botts L.L.P., Houston, TX, argued for defendants-appellees AT&T Corp., AT&T 

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2 UNITED ACCESS TECHNOLOGIES, LLC v. AT&T CORP. 

Services, Inc., SBC Internet Services, Inc. Also represented by JOHN GAUSTAD, JON V. SWENSON, Palo Alto, CA; 

DOUGLAS M. KUBEHL, Dallas, TX.

 MATTHEW CHRISTOPHER GAUDET, Duane Morris LLP, 

Atlanta, GA, for defendants-appellees CenturyTel Broadband Services LLC, Qwest Corporation. Also represented 

by ALEKSANDER JERZY GORANIN, Philadelphia, PA.

 ______________________ 

Before LOURIE, BRYSON, and PROST, Circuit Judges.

BRYSON, Circuit Judge.

In these two related patent cases, appellant United Access Technologies, LLC, (“UAT”) appeals from the district 

court’s grant of summary judgment of non-infringement.1 

We affirm in one of the two cases and dismiss in the other.

I 

 These cases have come before us on two prior occasions. 

In United Access Techs., LLC v. CenturyTel Broadband 

Servs. LLC (UAT I), 778 F.3d 1327 (Fed. Cir. 2015), we held 

that a prior jury verdict of non-infringement in a case involving a different defendant, Earthlink, Inc, did not collaterally estop UAT from bringing an infringement action 

against CenturyTel. In United Access Techs., LLC v. AT&T 

Corp. (UAT II), 757 F. App’x 960 (Fed. Cir. 2019), we affirmed the district court’s holding that the asserted claims 

were not indefinite and modified the district court’s construction of a disputed claim term. A thorough discussion 

1 Appeal No. 21-2002 relates to UAT’s infringement 

action against AT&T Corp., AT&T Services, Inc., and SBC 

Internet Services, Inc. (collectively, “AT&T”). Appeal No. 

21-2007 relates to UAT’s infringement action against CenturyTel Broadband Services LLC and Qwest Corporation 

(collectively, “CenturyTel”).

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UNITED ACCESS TECHNOLOGIES, LLC v. AT&T CORP. 3

of the factual background of these cases can be found in 

those earlier opinions.

In the two complaints, UAT alleged that AT&T and 

CenturyTel infringed various claims of three patents: U.S. 

Patent No. 5,844,596 (“the ’596 patent”); U.S. Patent No. 

6,243,446 (“the ’446 patent”); and U.S. Patent No. 

6,542,585 (“the ’585 patent”). The asserted patents are directed to a system for facilitating “simultaneous two-way 

communication of video signals and other signals between 

multiple networks of telephone wiring.” ’596 patent, col. 1, 

ll. 23–25. In the systems described by the patents, video 

signals are transmitted on the same lines as telephone signals, but on different frequencies from the telephone signals. Id. at col. 3, line 58, through col. 4, line 6. Such a 

system “eliminates the need for installation of multiple coaxial branches within a residence.” Id. at col. 3, ll. 33–34.

Claim 61 of the ’596 patent is representative. It recites:

61. A system for communicating information between an external source of information and a plurality of destinations of information over a 

telephone wiring network used for passing telephone signals in a telephone voice band between a 

plurality of telephone devices and a telephone exchange, comprising:

a plurality of transceivers coupled between 

the telephone wiring network and corresponding destinations of information, each 

including

circuitry for accepting signals in a 

high frequency band of frequencies 

above the highest frequency of the 

telephone voice band and rejecting 

signals in the telephone voice band; 

and

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4 UNITED ACCESS TECHNOLOGIES, LLC v. AT&T CORP. 

a signal interface coupled between the external source of information and the telephone wiring network, including

circuitry for receiving a plurality of 

external signals encoding a plurality of information streams from the 

external source of information, and

circuitry for transmitting to selected sets of one or more of the plurality of transceivers a 

corresponding plurality of internal 

signals in the high frequency band 

each encoding one of the plurality 

of information streams over the telephone wiring network;

wherein the telephone wiring network includes a branch network which couples one 

of the plurality of telephone devices to the 

telephone exchange telephone exchange 

[sic], and the branch network includes circuitry for preventing transmission of signals in the high frequency band to the one 

of the telephone devices on the branch network.

The dispute in this appeal focuses on the term “signal 

interface.” In UAT II, we held that the term “signal interface” refers to “a device interposed on the opposite end (i.e., 

the local side) of the public trunk line (i.e., on the local side 

of the telephone lines comprising the public telephone network) from the telephone exchange that performs the recited functions of the incorporated circuitry.” UAT II, 757 

F. App’x at 968. We also held that the “public telephone 

network” is not defined by whether the lines are owned by 

the telephone company. Id.

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UNITED ACCESS TECHNOLOGIES, LLC v. AT&T CORP. 5

AT&T’s accused systems contain a Digital Subscriber 

Line Access Multiplexer (“DSLAM”), which UAT argues is

the “signal interface” referred to in the claims. In the accused systems that are the focus of this appeal, the DSLAM 

is located inside a “remote terminal.” The remote terminal 

resides between the telephone company’s central office (or

“telephone exchange”) and customer residences.2 From the 

remote terminal, signals are transmitted along bundled 

groups of twisted-wire pairs toward the customers’ residences.

AT&T’s systems also include “serving terminals” that 

are located between the remote terminals and the customers’ residences. A serving terminal is not capable of transforming or modifying the signals it receives; it merely 

connects each twisted-wire pair entering the serving terminal with a single twisted-wire pair leaving the serving terminal. Upstream of the serving terminal, the twisted-wire 

pairs carrying signals destined for specific subscribers are 

bundled together. Downstream of the serving terminal, 

the twisted wire pairs are separately directed to customers’ 

residences.3 The dispute in these cases centers on where 

the “public trunk line” ends. If it ends downstream of the 

DSLAM (e.g., at the serving terminal), the DSLAM cannot 

satisfy the “signal interface” limitation because the 

DSLAM is not on “the local side” of the public trunk line. 

See UAT II, 757 F. App’x at 968. By contrast, if the public 

trunk line ends at or upstream of the remote terminal, 

AT&T’s DSLAMs may satisfy that limitation.

2 UAT also accused other systems in which the 

DSLAM was positioned in the telephone company’s central 

office, but those systems are no longer at issue in this case.

3 “Upstream” refers to signals being transmitted in 

the direction of the central office, and “downstream” refers 

to signals being transmitted in the direction of the individual residences.

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6 UNITED ACCESS TECHNOLOGIES, LLC v. AT&T CORP. 

On remand from our decision in UAT II, the defendants 

moved for summary judgment of noninfringement. The 

district court granted the motion, holding that the undisputed evidence established that in the accused systems

“the boundary between the local and non-local portions of 

the public telephone network is at a point downstream of 

the remote terminal.” United Access Techs., LLC v. AT&T 

Corp. (Summary Judgment Op.), No. 1:11-cv-338, 2021 WL 

1840785, at *6 (D. Del. Apr. 30, 2021). The district court 

noted that UAT had not offered evidence to the contrary, 

because “UAT’s expert only analyzed the nature of the lines 

upstream, not downstream, of the remote terminal.” Id. 

These appeals followed. 

II

A 

We begin by addressing our jurisdiction. We have jurisdiction over an appeal from a final decision of a district 

court. 28 U.S.C. § 1295(a)(1). In these cases, the district 

court’s grant of summary judgment of non-infringement resolved all of UAT’s claims against the defendants. The district court declined to enter a final judgment in either case, 

however, due to a pending counterclaim of invalidity in the 

CenturyTel case. See generally United Access Techs., LLC 

v. CenturyTel Broadband Servs., LLC, No. 1:11-cv-339, 

Dkt. No. 352 (D. Del. May 13, 2021) (Transcript of May 12, 

2021, teleconference). Without obtaining the district 

court’s approval, the parties then stipulated to a withoutprejudice dismissal of CenturyTel’s counterclaim under 

Federal Rule of Civil Procedure 41(a)(1)(A)(ii), and UAT 

subsequently filed notices of appeal in both cases. 

We have repeatedly held that an order adjudicating a 

plaintiff’s infringement claims is not an appealable order if 

an unadjudicated counterclaim of invalidity remains pending. Pause Tech. LLC v. TiVo Inc., 401 F.3d 1290, 1293–94

(Fed. Cir. 2005); Nystrom v. TREX Co, 339 F.3d 1347, 1351 

(Fed. Cir. 2003). Baker v. Microsoft Corp., No. 2017-1928, 

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UNITED ACCESS TECHNOLOGIES, LLC v. AT&T CORP. 7

2017 WL 4685332, at *1 (Fed. Cir. June 13, 2017). In this 

circuit, a court-approved dismissal of all remaining claims, 

whether with or without prejudice, is sufficient to create 

finality for purposes of appellate jurisdiction. See Atlas IP, 

LLC v. Medtronic, Inc., 809 F.3d 599, 604–05 (Fed. Cir. 

2015). But the stipulation of dismissal without prejudice 

in the CenturyTel case was made without the approval of 

the district court. There was therefore no final appealable 

order in that case. See Robinson-Reeder v. Am. Council on 

Education, 571 F.3d 1333, 1339–40 (D.C. Cir. 2009) (holding that a stipulation of dismissal without prejudice under 

Rule 41(a)(1)(A)(ii), made without the district court’s approval, did not create finality under 28 U.S.C. § 1291, the 

statute analogous to our jurisdictional statute, 28 U.S.C. 

§ 1295). 

 Accordingly, the appeal in the CenturyTel case, No. 21-

2007, is dismissed. In case No. 21-2002, AT&T did not file 

a counterclaim, and we therefore have jurisdiction over 

that appeal.4 For that reason, we proceed to the merits 

with respect to the appeal in case No. 21-2002. 

B 

In challenging the district court’s summary judgment 

order, UAT raises two arguments. First, UAT argues that 

the district court imported an additional limitation into the

claims when it concluded that the public trunk line ends at 

the “furthest downstream point of convergence.” See 

4 The district court never entered a final judgment 

in the AT&T case, but the failure to docket a document labeled “judgment” does not preclude appellate jurisdiction 

so long as all claims in the action have been resolved. See 

FirsTier Mortg. Co. v. Invs. Mortg. Ins. Co., 498 U.S. 269, 

277 (1991) (holding that a summary judgment ruling resolving all of the plaintiff’s claims was final, even though a 

final judgment had not formally been entered). 

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8 UNITED ACCESS TECHNOLOGIES, LLC v. AT&T CORP. 

Summary Judgment Op. at *6. Second, UAT argues that 

there was sufficient evidence in the record to create a triable issue of fact with respect to literal infringement of the 

asserted claims. Because UAT has not raised a triable issue with respect to whether the public trunk line ends at 

the DSLAM, we affirm without reaching UAT’s argument 

regarding the “furthest downstream point of convergence.”

The district court granted summary judgment because 

“there [was] nothing to support UAT’s argument that the 

remote terminal, containing the DSLAM, is on the local 

side of the network.” Id. at *4. We agree. UAT offered no 

evidence that AT&T’s remote terminals were located downstream of the public trunk line. 

In support of its contention that AT&T’s remote terminals are not on the public trunk line, UAT points to three 

excerpts from the report of its expert, Dr. Tim Williams. 

First, UAT points to Dr. Williams’ assertion that the remote terminal “is downstream of the telephone exchange, 

towards the local (customer) end of the overall network” 

and that the DSLAM is “interposed on the local side of the 

public trunk line from the telephone exchange, and opposite the telephone exchange.” J.A. 10846, ¶ 324; see also 

J.A. 10848, ¶ 331. Second, UAT points to a series of diagrams that denote the lines running between the remote 

terminal and the serving terminal as “extended pairs.” 

See, e.g., J.A. 10839, 10841. Third, UAT calls our attention 

to Dr. Williams’ statement that “[f]or each of AT&T’s accused systems, the DSLAM acts as the signal interface.” 

J.A. 10846, ¶ 322. 

There are two problems with that evidence. First, 

while those statements assert that the DSLAM is “on the 

local side” of the public trunk line from the telephone exchange, they do not squarely address the question whether 

any of the lines downstream of the DSLAM are part of the 

public trunk line. In fact, at his deposition, Dr. Williams

made clear that he was not taking a position on that issue:

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Q: And are there any telephone lines comprising 

the public telephone network downstream of the 

remote terminal?

A: I have not expressed that opinion.

Q: You’ve provided no opinion that there are or 

are not telephone lines comprising the public telephone network downstream of AT&T’s remote terminals; is that correct?

A: No, not correct.

Q: Well, do you have an opinion that there are no 

telephone lines comprising the public telephone 

network downstream of AT&T’s remote terminals?

A: Again, I have not expressed that opinion; however, to find infringement, I would have to find a 

signal interface which, as defined by the court, is a 

device interposed on the opposite end of the public 

trunk line from the telephone exchange that performs the recited functions of the incorporated circuitry.

So the signal interface would need to be at the 

opposite end of the public trunk line from the telephone exchange. And you’re asking me about other 

architectures that I have not expressed an opinion 

on.

Q: So you have not expressed an opinion that 

there are no telephone lines comprising the public 

telephone network downstream of AT&T’s accused 

remote terminals?

A: I believe I’ve testified as to that at least three 

times now. 

J.A. 6686–87 (lightly edited for readability). 

Second, even if the statements in Dr. Williams’ report 

were squarely directed to whether the DSLAMs in AT&T’s 

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10 UNITED ACCESS TECHNOLOGIES, LLC v. AT&T CORP. 

system are on the local lines rather than on the public 

trunk lines, those statements are wholly conclusory. Such 

statements are not sufficient, standing alone, to create a 

triable issue of fact with regard to infringement. Arthur A. 

Collins, Inc. v. N. Telecom Ltd., 216 F.3d 1042, 1047 (Fed. 

Cir. 2000) (“[A] party may not avoid summary judgment

simply by offering an opinion of an expert that states, in 

effect, that the critical claim limitation is found in the accused device.”); see also Novartis Corp. v. Ben Venue Lab’ys, 

Inc., 271 F.3d 1043, 1051 (Fed. Cir. 2001) (“If all expert 

opinions on infringement or noninfringement were accepted without inquiry into their factual basis, summary 

judgment would disappear from patent litigation.”).

Accordingly, UAT has not pointed to evidence that 

raises a jury question as to literal infringement. That is 

true regardless of whether the district court was correct in 

stating that the public trunk line must end at the “furthest 

downstream point of convergence.” Summary Judgment 

Op. at *6. We therefore need not reach that issue.

C 

UAT argues that even if the district court was correct 

to grant summary judgment with respect to literal infringement, the court should have permitted UAT to proceed to trial on a doctrine-of-equivalents theory. 

In general, “to find infringement under the doctrine of

equivalents, any differences between the claimed invention 

and the accused product must be insubstantial.” Brilliant 

Instruments, Inc. v. GuideTech, LLC, 707 F.3d 1342, 1346–

47 (Fed. Cir. 2013) (citing Graver Tank & Mfg. Co. v. Linde 

Air Prods. Co., 339 U.S. 605, 608 (1950)). However, when 

the alleged equivalent would “vitiate an element of the 

claims,” there can be no infringement under the doctrine of 

equivalents. Decisioning.com, Inc. v. Federated Dep’t 

Stores, Inc., 527 F.3d 1300, 1315 (Fed. Cir. 2008). A claim 

term is vitiated when the proposed equivalency “embrace[s] a structure that is specifically excluded from the 

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UNITED ACCESS TECHNOLOGIES, LLC v. AT&T CORP. 11

scope of the claims.” Athletic Alternatives, Inc. v. Prince 

Mfg., Inc., 73 F.3d 1573, 1582 (Fed. Cir. 1996) (citation 

omitted).

Under the claim construction that we adopted in UAT 

II, the signal interface must be positioned “on the opposite 

end (i.e., the local side) of the public trunk line.” UAT II, 

757 F. App’x at 968. In its summary judgment opinion, the

district court held that UAT could not proceed under the 

doctrine of equivalents because “the purposes behind the 

locational limitation would be vitiated by treating the 

DSLAM in the remote terminal as the signal interface.” 

Summary Judgment Op. at *5. We agree.

The specifications of the asserted patents provide two 

reasons for positioning the signal interface at the local end 

of the public trunk line. First, one function of the signal 

interface is to filter out high-frequency signals before they 

are conducted onto the public telephone line, because governmental regulations “severely limit[] the energy that can 

be conducted onto the public network by signals above 

voiceband and below 6 Mhz.” ’596 patent, col. 48, ll. 37–46. 

Second, when telephone lines “run parallel and very close 

to each other for a long distance,” there is “a significant 

possibility of crosstalk interference between the various 

signals” being transmitted on each line. Id. at col. 17, ll. 

30–38. As noted by AT&T’s expert, Dr. Matthew Shoemake, the positional limitation of the signal interface is informed by both of those considerations. J.A. 6799 at ¶ 234 

n.25.

To allow the signal interface to be placed on the public 

trunk line would undercut both of those considerations. 

Placing the signal interface on the public trunk line would 

necessarily require that high-frequency signals travel upstream along the public trunk line until they reach the signal interface, potentially running afoul of the government 

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12 UNITED ACCESS TECHNOLOGIES, LLC v. AT&T CORP. 

regulations described in the patents.5 Likewise, placing 

the signal interface at a point on the public trunk line 

would increase the distance between the individual residences and the signal interface, thus increasing the risk of 

crosstalk among the twisted-wire pairs. 

As a result, to permit UAT to argue a theory of infringement that allows the signal interface to be located along 

the public trunk line at some distance from the local lines 

would “embrace a structure that is specifically excluded 

from the scope of the claims,” which require that the signal 

interface be located at the end of the public trunk line. See 

Athletic Alternatives, 73 F.3d at 1582 (citation omitted).

Furthermore, UAT has not suggested that the 

DSLAMs in AT&T’s systems are located so close to the intersection between the local lines and the public trunk 

lines that the positional difference between AT&T’s systems and the structure claimed in the asserted patents is 

insubstantial. As AT&T points out, UAT’s arguments regarding the doctrine of equivalents would appear to apply 

to placing the signal interface anywhere on the public 

trunk line, which would effectively eliminate the positional 

limitation of the claimed “signal interface” in its entirety.

The district court therefore did not err in determining

that “the purposes behind the locational limitation would 

be vitiated by treating the DSLAM in the remote terminal 

as the signal interface.” Summary Judgment Op. at *5. We 

therefore uphold the district court’s grant of summary 

judgment of non-infringement to AT&T on both literal 

5 At oral argument, AT&T explained that its accused 

systems do not violate the government regulations discussed in the patents because AT&T is able to minimize 

the energy that is conducted at high frequencies onto the 

public telephone network so that AT&T is in compliance 

with those regulations. See Oral Argument at 27:23–28:52.

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UNITED ACCESS TECHNOLOGIES, LLC v. AT&T CORP. 13

infringement and infringement under the doctrine of 

equivalents. 

Costs to the appellees.

AFFIRMED-IN-PART AND DISMISSED-IN-PART

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