United Access Technologies, LLC v. At&t Corp.

Case: 21-2002 Document: 62 Page: 1 Filed: 04/15/2022

NOTE: This disposition is nonprecedential.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-cv-
00339-KAJ, Circuit Judge Kent A. Jordan.
______________________

Decided: April 15, 2022
______________________

ANTHONY MATTHEW GARZA, Charhon, Callahan, Rob-
son, & Garza PLLC, Dallas, TX, argued for plaintiff-appel-
lant. Also represented by STEVEN CHASE CALLAHAN, BRETT
CHARHON.

MICHAEL HAWES, Baker Botts L.L.P., Houston, TX, ar-
gued for defendants-appellees AT&T Corp., AT&T
Case: 21-2002 Document: 62 Page: 2 Filed: 04/15/2022

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

Services, Inc., SBC Internet Services, Inc. Also repre-
sented 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 Broad-
band 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 Ac-
cess 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 in-
volving a different defendant, Earthlink, Inc, did not col-
laterally 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 af-
firmed the district court’s holding that the asserted claims
were not indefinite and modified the district court’s con-
struction 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 Cen-
turyTel 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 di-
rected 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 sig-
nals, but on different frequencies from the telephone sig-
nals. Id. at col. 3, line 58, through col. 4, line 6. Such a
system “eliminates the need for installation of multiple co-
axial 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 be-
tween an external source of information and a plu-
rality of destinations of information over a
telephone wiring network used for passing tele-
phone signals in a telephone voice band between a
plurality of telephone devices and a telephone ex-
change, comprising:
a plurality of transceivers coupled between
the telephone wiring network and corre-
sponding 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 ex-
ternal source of information and the tele-
phone wiring network, including
circuitry for receiving a plurality of
external signals encoding a plural-
ity of information streams from the
external source of information, and
circuitry for transmitting to se-
lected sets of one or more of the plu-
rality of transceivers a
corresponding plurality of internal
signals in the high frequency band
each encoding one of the plurality
of information streams over the tel-
ephone wiring network;
wherein the telephone wiring network in-
cludes a branch network which couples one
of the plurality of telephone devices to the
telephone exchange telephone exchange
[sic], and the branch network includes cir-
cuitry for preventing transmission of sig-
nals in the high frequency band to the one
of the telephone devices on the branch net-
work.
The dispute in this appeal focuses on the term “signal
interface.” In UAT II, we held that the term “signal inter-
face” 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 net-
work) from the telephone exchange that performs the re-
cited 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 ac-
cused 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’ resi-
dences.
AT&T’s systems also include “serving terminals” that
are located between the remote terminals and the custom-
ers’ residences. A serving terminal is not capable of trans-
forming or modifying the signals it receives; it merely
connects each twisted-wire pair entering the serving termi-
nal with a single twisted-wire pair leaving the serving ter-
minal. 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 individ-
ual 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 undis-
puted 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 ju-
risdiction 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 re-
solved all of UAT’s claims against the defendants. The dis-
trict 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 without-
prejudice 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 pend-
ing. 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) (hold-
ing that a stipulation of dismissal without prejudice under
Rule 41(a)(1)(A)(ii), made without the district court’s ap-
proval, 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 la-
beled “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 re-
solving 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 tria-
ble issue of fact with respect to literal infringement of the
asserted claims. Because UAT has not raised a triable is-
sue 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 down-
stream of the public trunk line.
In support of its contention that AT&T’s remote termi-
nals 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 re-
mote 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 oppo-
site the telephone exchange.” J.A. 10846, ¶ 324; see also
J.A. 10848, ¶ 331. Second, UAT points to a series of dia-
grams 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 ac-
cused 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 ex-
change, 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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UNITED ACCESS TECHNOLOGIES, LLC v. AT&T CORP. 9

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 tele-
phone network downstream of AT&T’s remote ter-
minals; 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; how-
ever, 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 per-
forms the recited functions of the incorporated cir-
cuitry.
So the signal interface would need to be at the
opposite end of the public trunk line from the tele-
phone 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 ac-
cused 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 ac-
cepted 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 in-
fringement, the court should have permitted UAT to pro-
ceed 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 “em-
brace[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 gov-
ernmental 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 Shoe-
make, the positional limitation of the signal interface is in-
formed 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 up-
stream along the public trunk line until they reach the sig-
nal 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 resi-
dences 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 infringe-
ment 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 in-
tersection between the local lines and the public trunk
lines that the positional difference between AT&T’s sys-
tems and the structure claimed in the asserted patents is
insubstantial. As AT&T points out, UAT’s arguments re-
garding 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 dis-
cussed 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