Tracktime, LLC v. Amazon.com Services LLC, Audible, Inc.

United States Court of Appeals
for the Federal Circuit
______________________
TRACKTIME, LLC,
Plaintiff-Appellant
v.
AMAZON.COM SERVICES LLC, AUDIBLE, INC.,
Defendants-Appellees
______________________
2024-1102
______________________
Appeal from the United States District Court for the
District of Delaware in No. 1:18-cv-01518-MN, Judge
Maryellen Noreika.
______________________
Decided: July 2, 2026
______________________
ROBERT G REENSPOON, Dunlap Bennett & Ludwig
PLLC, Chicago, IL, argued for plaintiff-appellant. Also
represented by WILLIAM W. F LACHSBART .
J. D AVID HADDEN , Fenwick & West LLP, Mountain
View, CA, argued for defendants-appellees. Also repre-
sented by RAVI RAGAVENDRA RANGANATH , SAINA S.
SHAMILOV; T ODD RICHARD G REGORIAN, San Francisco, CA;
MELANIE L YNE MAYER, J ONATHAN T HOMAS MCMICHAEL ,
Seattle, WA.
______________________
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 2
Before P ROST and T ARANTO, Circuit Judges, and K OVNER ,
District Judge.1
T ARANTO, Circuit Judge.
TrackTime, LLC owns U.S. Patent Nos. 8,856,638 and
8,862,978, which it asserted against Amazon.com Services
LLC and several other entities (collectively, Amazon) in an
infringement action it filed in the United States District
Court for the District of Delaware. TrackTime’s patents
claim methods and systems for use on a mobile device to
navigate within a multimedia file by using a time-corre-
lated transcript. For the ’978 patent, the district court con-
strued two limitations of the asserted claims—reciting, for
mobile devices, “executable program code configured to fa-
cilitate annotation” and “executable program code config-
ured to synchronously play . . . multimedia”—as means-
plus-function claim terms subject to 35 U.S.C. § 112(f), and
it then held the asserted claims invalid for indefiniteness
because the patent’s written description has inadequate
disclosure of structure corresponding to those terms.
TrackTime, LLC v. Amazon.com, Inc., No. 18-cv-1518,
2021 WL 2823163, at *5–8 (D. Del. July 7, 2021) (Claim
Construction Order). For the ’638 patent, the only claim
now at issue is claim 9, which a jury found to be invalid and
also not infringed, and the district court denied post-trial
motions to set aside the verdict. TrackTime, LLC v. Ama-
zon.com, Inc., No. 18-cv-1518, 2024 WL 4300101, at *3–14
(D. Del. Sept. 26, 2024) (JMOL Decision). TrackTime ap-
peals.
Regarding the ’978 patent, TrackTime argues that the
disputed “executable program code” limitations should not
be treated as § 112(f) means-plus-function terms under the
1 Honorable Rachel P. Kovner, District Judge,
United States District Court for the Eastern District of
New York, sitting by designation.
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 3
approach set forth in our decision in Dyfan, LLC v. Target
Corp., 28 F.4th 1360 (Fed. Cir. 2022), which issued after
the district court ruled on the matter in this case. We agree
to this extent: Further analysis of the issue is warranted in
light of our intervening precedent. Because the needed
analysis may benefit from new factual as well as legal sub-
missions, we vacate the district court’s indefiniteness rul-
ing and remand for further proceedings to determine
whether § 112(f) applies (and, if so, is satisfied).
Regarding the ’638 patent, TrackTime challenges the
judgment on the verdict on several grounds. We affirm the
judgment of invalidity under 35 U.S.C. § 102 for anticipa-
tion. We need not address TrackTime’s other challenges.
I
A
The ’978 and ’638 patents share a specification in all
respects material here. Unless otherwise indicated, we cite
only the ’978 patent’s specification.
The specification addresses navigating, on a mobile de-
vice, through multimedia files containing audible words.
See ’978 patent, col. 3, line 54, through col. 4, line 5. For a
given multimedia file, the specification describes creating
a “synchronization index,” i.e., a transcript indicating, by
an accompanying time specification, “when a word or range
of words is audible in the multimedia.” Id., col. 3, lines 54–
63. The index makes possible “tap-to-jump” functionality
(TrackTime Opening Br. at 2): When a synchronization in-
dex is displayed on a user’s touch-sensitive mobile device,
the user can tap a portion of the text to play the correspond-
ing portion of the multimedia file. ’978 patent, col. 1, lines
58–62; col. 33, lines 47–53; col. 40, lines 20–27. The user
also can annotate the synchronization index (e.g., with
color-coded highlighting or the user’s comments) and can
then share the annotated synchronization index with
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 4
others. Id., col. 64, lines 42–53; see also id., col. 49, lines
12–38.
The specification discloses that “transcript manage-
ment utilities” existed in the prior art, id., col. 6, lines 1–
14, and that there were known methods for making syn-
chronization indices, id., col. 8, lines 5–15, for using the in-
dex to navigate to a position in a multimedia file and
playing the located content, id., col. 8, lines 47–61, and for
annotating transcripts, id., col. 6, lines 38–55. But the
specification identifies two limitations of the prior-art
methods: First, “some transcript management utilities”
could only “operate on a full version of Microsoft Windows,”
which the specification calls “unsuitable for mobile compu-
ting devices,” id., col. 6, lines 11–17; second, the functions
of creating a synchronization index, annotating it, and us-
ing it to navigate multimedia, among others, were scat-
tered across “disparate software applications,” id., col. 8,
lines 15–22; see id., col. 11, lines 39–57.
The specification proposes to “solve . . . these shortcom-
ings” by providing a “synchronization index and software
suited for use on a mobile computing device” facilitating
“convenient navigation” and “annotation,” among other ca-
pabilities. Id., col. 11, lines 15–38; see id., col. 3, line 54,
through col. 4, line 5. In one embodiment of the assertedly
inventive system, a mobile computing device communi-
cates with a web application for transcript management.
See id., col. 27, lines 19–40. The web application includes
several kinds of “logic,” including “annotation and edit
logic” and “video, display, and playlist logic.” Id., col. 27,
lines 27–35; id., fig. 6. The mobile computing device, in
turn, has its own software (including “logic”) for communi-
cating with the web application, synchronously playing
multimedia with a scrolling transcript, navigating by using
the transcript, and annotating the transcript, among other
functions. See id., col. 32, line 37, through col. 38, line 59.
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 5
The claims most relevant to this appeal are claims 1
and 2 of the ’978 patent and claim 9 of the ’638 patent.
Claims 1 and 2 of the ’978 patent are shown here:
1. A method for social networking with a mobile
computing device comprising:
providing for use on a mobile computing device a
synchronization index, wherein said synchroniza-
tion index is associated to multimedia, wherein the
synchronization index comprises an electronic
transcript that indicates text corresponding to au-
dio from the multimedia, and wherein the synchro-
nization index indicates respective times within
the multimedia corresponding to when a word or
range of words is audible in the multimedia;
providing mobile computing device software,
wherein said mobile computing device software
comprises executable program code configured to
receive the synchronization index, and wherein
said text is able to be displayed other than as a web
page,
wherein said mobile computing device comprises a
viewing screen and a touch-sensitive input inter-
face,
wherein said viewing screen is able to display mul-
timedia and text from said synchronization index,
wherein performing a user’s selected gesture on a
portion of said viewing screen corresponding to a
portion of said text is recognized by said touch-sen-
sitive input interface to facilitate annotation of a
portion of said synchronization index, and
wherein said mobile computing device soft-
ware comprises executable program code
configured to facilitate annotation of a por-
tion of said synchronization index responsive
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 6
to user input received by the mobile compu-
ting device; and
communicating said annotation for subsequent re-
trieval on a second computing device via a network.
2. The method of claim 1, wherein said mobile
computing device software comprises execut-
able program code configured to synchro-
nously play said associated multimedia with
said synchronization index other than as part
of a web page.
Id., col. 64, lines 23–57 (emphases added).
Claim 9 of the ’638 patent is reproduced here:
9. A method for a multimedia seek sequence using
a synchronization index and a mobile computing
device comprising the steps:
displaying on a mobile computing device text from
a synchronization index, wherein said synchroniza-
tion index comprises respective times within mul-
timedia corresponding to a word or range of words
and wherein said text is displayed other than as a
web page;
wherein said mobile computing device comprises a
viewing screen and a touch-sensitive input inter-
face;
receiving information indicating a user’s selected
mobile computing device touch-sensitive input in-
terface gesture performed on a portion of said view-
ing screen corresponding to a word, or range of
words, from said synchronization index, wherein
said gesture is recognized by said touch-sensitive
input interface;
performing a data lookup using said synchroniza-
tion index, wherein said synchronization index is
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 7
referenced to provide data for a time location t1
that corresponds to said word or range of words se-
lected by the recognized gesture; and
seeking on said mobile computing device multime-
dia corresponding to said synchronization index,
and if found, accessing multimedia at t1.
’638 patent, col. 65, lines 44–67.
B
TrackTime sued Amazon for infringement of the ’638
and ’978 patents in the District of Delaware in October
2018. See J.A. 235. Amazon, as now relevant, contended
that the asserted claims (claims 1–10, all of which depend
on claim 1) of the ’978 patent were invalid for indefinite-
ness, J.A. 1378–84, 1398–99, and that claim 9 of the ’638
patent was invalid for anticipation by a reference called
LiveNote, see J.A. 5381.
1
The district court conducted claim-construction pro-
ceedings that led to a holding of invalidity of the asserted
claims of the ’978 patent in July 2021. Claim Construction
Order, at *1. Amazon argued invalidity for indefiniteness
in two steps. First, Amazon argued, the two “executable
program code” limitations highlighted above—the mobile-
device code “configured to facilitate annotation of a portion
of [the] synchronization index” (claim 1) and “configured to
synchronously play . . . multimedia” (claim 2)—were
means-plus-function claim terms under 35 U.S.C. § 112(f).2
2 The applications that issued as the patents here
were both filed on December 6, 2013. J.A. 59, 142. The
Leahy-Smith America Invents Act (AIA) amended § 112
with respect to “‘any patent application that is filed on or
after’ September 16, 2012.” D Three Enterprises, LLC
v. SunModo Corp., 890 F.3d 1042, 1045 n.4 (Fed. Cir. 2018)
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 8
Second, Amazon added, indefiniteness followed because
the specification did not disclose corresponding structure
for the claimed functions, as required for a § 112(f) term.
See J.A. 1379–84, 1398–99. In support, Amazon cited the
declaration of its expert, Dr. Dan Schonfeld, who stated
that the terms “do not inform a [relevant artisan] what the
underlying algorithms or instructions are” for the claimed
code and that the inclusion of a “mobile computing device”
in the claim did not “provide any additional details . . .
about the structure performing the recited [ ] function[s].”
J.A. 1478; see J.A. 1482; J.A. 1379, 1398. TrackTime re-
plied that the terms were not governed by § 112(f), because,
according to TrackTime’s expert, Dr. Maneesh Agrawala,
the terms would have been understood by relevant artisans
at the time of the invention to refer to specific types of code
within existing programs, including, for example, the Liv-
eNote program alleged by Amazon to be anticipatory. See
J.A. 1385–89, 1400–01 (citing J.A. 1635–44). TrackTime
also argued that the specification’s disclosures of numerous
subsidiary functions of the annotation and synchronous-
play logic described the operation of the claimed code with
enough specificity that the claims conveyed adequate
structure to relevant artisans. J.A. 1389–91, 1402–03.
The district court, in a July 2021 order, agreed with
Amazon that the “executable program code” limitations are
means-plus-function terms and that the specification lacks
adequate disclosure of corresponding structure, so held the
claims invalid for indefiniteness. Claim Construction Or-
der, at *5–8. As to whether § 112(f) applied at all, the dis-
trict court recognized that, because “means” is not used in
the claims, it presumed that § 112(f) did not apply, but the
(quoting Pub. L. No. 112-29, § 4(c), 125 Stat. 284, 296–97
(2011)). Post-AIA § 112(f) therefore applies here, not its
pre-AIA predecessor (35 U.S.C. § 112 ¶ 6 (2008)), though
no material difference has been identified in this case.
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 9
court held that the presumption was rebutted. In particu-
lar, the term “executable program code” (and, similarly, the
“logic” referred to in the specification), the district court
reasoned, is merely “generic,” rather than indicating suffi-
ciently specific structure, and although the specification re-
fers to prior-art programs, it “does not state that these
prior art software applications contain the claimed execut-
able program code.” Id., at *5–6. Having held § 112(f) to
be applicable, the district court then concluded that the
specification lacks sufficient disclosure of an “algorithm or
procedure that explains how” the executable program code
accomplishes the claimed functions. Id., at *7. Accord-
ingly, it held the claims invalid. See id., at *8.
2
TrackTime tried its case of infringement of the ’638 pa-
tent to a jury in September 2023. J.A. 265–66. Although
TrackTime pressed claims 1 and 9, the present appeal re-
lates only to claim 9. See JMOL Decision, at *1 & n.1,
*3 & n.3; TrackTime Opening Br. at 3. Amazon disputed
infringement and also pressed invalidity assertions, invok-
ing ineligibility, 35 U.S.C. § 101, anticipation, § 102, obvi-
ousness, § 103, and inadequacy of written-description
support, § 112(a). See J.A. 5379–83.
The jury rejected the written-description challenge but
otherwise agreed with Amazon on claim 9—finding no in-
fringement, anticipation by each of three references, obvi-
ousness in light of one of those references, and ineligibility.
J.A. 5379–83. As most relevant now, the jury was pre-
sented with evidence about LiveNote, a commercial pro-
gram that is described in three Amazon trial exhibits: a
written installation guide, tutorial, and user guide. See
J.A. 8611–9105. The LiveNote user guide describes the
program as “enabl[ing a user] to organize, view, search,
and annotate transcripts,” and it highlights two “new fea-
tures for tablet PCs,” including the ability to “use [a] tablet
pen to write a note” in an “annotate dialog box” when
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 10
“using[ ] . . . a tablet PC.” J.A. 8758, 8762, 8906 (capitali-
zation altered). Dr. Schonfeld testified based on the user
guide that “[y]ou can use LiveNote with a desktop PC . . .,
but you can also use it with . . . a tablet PC [and] if it’s a
tablet PC, the document makes clear that you can tap on
the tablet and use it just like any other tablet, instead of
clicking.” J.A. 6145. Dr. Agrawala disagreed, opining that
the LiveNote user guide had no disclosure of claim 9’s “ges-
ture” for navigating a transcript, instead disclosing the use
of a tablet “just to annotate.” J.A. 6377–78. At trial, Track-
Time moved for judgment as a matter of law (JMOL) of in-
fringement and no invalidity as to claim 9, which motion
the district court denied. Trial Transcript, Tracktime
v. Amazon.com, Inc., No. 18-cv-1518, ECF No. 320 at 904,
926–27 (D. Del. Oct. 12, 2023). The jury found, among
other things, that claim 9 was anticipated by LiveNote.
J.A. 5381.
Following the jury’s verdict, TrackTime renewed its
motion for JMOL and moved for a new trial. J.A. 6631–56.
Regarding LiveNote, TrackTime argued that it was enti-
tled to judgment of no anticipation because “[t]he evidence
showed that LiveNote only discloses a tablet PC for . . . text
annotations . . ., not to navigate multimedia and not using
human touch gestures,” and it “indisputably used a big
desktop CPU, with [Microsoft] Windows, for its playback
operations, not a mobile device.” J.A. 6643–44. “For the
same reasons,” TrackTime contended, it should at least re-
ceive a new trial because the verdict went “against the
great weight of the evidence.” J.A. 6646 (capitalization al-
tered).
In September 2024, the district court denied the post-
trial motions. As to anticipation by LiveNote, the court
concluded that the LiveNote exhibits and Dr. Schonfeld’s
testimony “directly contradict[ed] [TrackTime’s] position”
and that the jury could have “reasonably concluded that
LiveNote anticipated” based on that evidence. JMOL
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 11
Decision, at *7. It rejected the clear-weight argument for a
new trial “substantially for the same reason[ ].” Id., at *8.
Thereafter the district court dismissed with prejudice
TrackTime’s infringement suit as to claims 2–8 and 10–20
of the ’638 patent, which had not been discussed at trial,
J.A. 31, and entered final judgment of noninfringement
and invalidity of ’638 claims 1 and 9. J.A. 32–33. The ear-
lier Claim Construction Order holding claims 1 and 2 of the
’978 patent invalid for indefiniteness merged into that final
judgment. See Fed. R. App. P. 3(c)(4). TrackTime timely
appealed. We have jurisdiction under 28 U.S.C.
§ 1295(a)(1).
II
TrackTime challenges the judgment of the district
court with respect to both patents. A determination that a
claim term invokes § 112(f) is a claim-construction issue
that we resolve without deference except to the extent that
the district court made legally pertinent findings of fact
based on extrinsic evidence, which we review for clear er-
ror. Williamson v. Citrix Online, LLC, 792 F.3d 1339, 1346
(Fed. Cir. 2015). We review the district court’s denial of
JMOL here without deference, following the law of the dis-
trict court’s regional circuit, the Third Circuit. Amgen Inc.
v. Hospira, Inc., 944 F.3d 1327, 1333 (Fed. Cir. 2019) (re-
viewing District of Delaware decision). When only eviden-
tiary sufficiency is at issue, JMOL is to be denied if there
is “enough evidence from which a jury reasonably could”
have found as it did. Secretary, United States Department
of Labor v. East Penn Manufacturing Co., 123 F.4th 643,
650–51 (3d Cir. 2024) (internal quotation marks and cita-
tion omitted). We review the district court’s denial of a new
trial for abuse of discretion. Amgen, 944 F.3d at 1333 (cit-
ing Third Circuit authority).
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 12
A
TrackTime urges us to reverse the district court’s in-
definiteness ruling on the ’978 patent, arguing that the “ex-
ecutable program code” limitations are not subject to
§ 112(f) and, even if they are, the specification discloses the
required corresponding structure that carries out the
claim-specified functions. We reach only the first part of
that submission. On the record and arguments presented
to us, we are not persuaded to hold, as TrackTime urges,
that the contested terms are outside § 112(f). We are per-
suaded, however, that the district court’s analysis, espe-
cially in light of our intervening Dyfan decision, was
insufficient to support the conclusion that the contested
terms come within § 112(f). We therefore vacate the dis-
trict court’s indefiniteness ruling and remand for a new de-
termination about the § 112(f) status of the “executable
program code” limitations, with proceedings appropriate to
making that new determination.
1
Under § 112(f), as relevant here, a claim element “may
be expressed as a means . . . for performing a specified
function without the recital of structure . . . in support
thereof,” and if the claim element is so written, it “shall be
construed to cover the corresponding structure . . . de-
scribed in the specification and equivalents thereof.”3 If a
3 The full language is: “An element in a claim for a
combination may be expressed as a means or step for per-
forming a specified function without the recital of struc-
ture, material, or acts in support thereof, and such claim
shall be construed to cover the corresponding structure,
material, or acts described in the specification and equiva-
lents thereof.” In this case, the parties do not rely on the
language of “step” or the corresponding word “acts” for the
claim elements at issue—referring to “executable program
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 13
claim element is subject to § 112(f), i.e., expressed in that
form, we search the specification for corresponding struc-
ture, and if sufficient structure is missing, the claim is in-
definite. Williamson, 792 F.3d at 1351–52.
Our focus here is on the first step of that inquiry, which
examines whether a claim phrase (“claim element”) is a
means-plus-function phrase, i.e., “expressed as a means . . .
for performing a specified function without the recital of
structure . . . in support thereof.” The question is one of
claim construction. Id. at 1346; see Dyfan, 28 F.4th at
1365–66; TEK Global, S.R.L v. Sealant Systems Interna-
tional, Inc., 920 F.3d 777, 785 (Fed. Cir. 2019). Specifically,
whether the words used themselves “recit[e]” structure for
performing the recited function(s) turns on the meaning of
those words in context, which can be informed not just by
the intrinsic evidence but also by evidence of extra-patent
usage in the relevant field (extrinsic evidence)—the latter
presenting an underlying issue of fact for the court. See
Dyfan, 28 F.4th at 1366; Inventio AG v. ThyssenKrupp El-
evator Americas Corp., 649 F.3d 1350, 1357 (Fed. Cir.
2011). The proponent of the means-plus-function construc-
tion has the burden to establish that the phrase is subject
to § 112(f), and where the claim construction involves an
underlying fact issue, the fact must be proved by a prepon-
derance of the evidence. See Dyfan, 28 F.4th at 1367; Ad-
vanced Ground Information Systems, Inc. v. Life360, Inc.,
830 F.3d 1341, 1347 (Fed. Cir. 2016) (both citing Apex Inc.
v. Raritan Computer Inc., 325 F.3d 1364, 1372 (Fed. Cir.
2003)).
Whether a claim phrase uses the word “means” does
not decisively determine whether the phrase is covered by
§ 112(f), but we have established presumptions to frame
code”—and they likewise do not rely on the word “mate-
rial.” We therefore focus on the statutory language about
“means” and “structure,” as have the parties.
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 14
the analysis. Whereas a claim phrase that uses “means” is
presumptively covered by § 112(f), a claim phrase that does
not use the word “means”—as is true in the present case—
is presumptively not expressed in means-plus-function
form. Williamson, 792 F.3d at 1348 (en banc in relevant
part). Importantly, the presumption relevant here is re-
buttable, i.e., a claim phrase that does not use “means” may
nonetheless, when properly understood, be shown to be one
“for performing a specified function without the recital of
structure . . . in support thereof.” 35 U.S.C. § 112(f).
Reflecting the language of the statute, our precedents
direct inquiry to whether the claim phrase “recites ‘func-
tion without reciting sufficient structure for performing
that function.’” Williamson, 792 F.3d at 1348 (quoting
Watts v. XL Systems, Inc., 232 F.3d 877, 880 (Fed. Cir.
2000)). One way to establish that condition is to show that
the phrase “refers only to a general category of whatever
may perform specified functions,” Robert Bosch, LLC
v. Snap-On Inc., 769 F.3d 1094, 1099 (Fed. Cir. 2014); see
Egenera, Inc. v. Cisco Systems, Inc., 972 F.3d 1367, 1374
(Fed. Cir. 2020), as when the relevant non-function term in
the phrase is as devoid of specificity of structure as the
word “means” (hence is, in that way, a “nonce” term)—as
can be true of, e.g., “module,” “mechanism,” “element,” or
“device” if viewed in isolation, Williamson, 792 F.3d at
1350; see MTD Products Inc. v. Iancu, 933 F.3d 1336, 1341
(Fed. Cir. 2019); Robert Bosch, 769 F.3d at 1099; Massa-
chusetts Institute of Technology & Electronics for Imaging,
Inc. v. Abacus Software, 462 F.3d 1344, 1354 (Fed. Cir.
2006). But the standard is not so limited. “The question is
not whether a claim term recites any structure but whether
it recites sufficient structure—a claim term is subject to
§ 112(f) if it recites ‘function without reciting sufficient
structure for performing that function.’” Egenera, 972 F.3d
at 1374 (quoting Williamson, 792 F.3d at 1348); see also
Sage Products, Inc v. Devon Industries, Inc., 126 F.3d 1420,
1427–28 (Fed. Cir. 1997) (stating that a phrase is outside
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 15
§ 112(f) if it recites enough matter “within the claim itself
to perform entirely the recited function”). In answering
that question, due effect must be given to the distinction
between “function” and “structure” on which § 112(f) is ex-
pressly built.
This inquiry usefully begins with parsing of the claim
phrase—identifying the portion that recites the function(s)
and the non-function term (a word or group of words) recit-
ing what performs the function(s). See Wenger Manufac-
turing v. Coating Machine Systems, Inc., 239 F.3d 1225,
1232–33 (Fed. Cir. 2001). Of significance here, correct
identification of the claimed function(s) is necessary not
only to determine what structures to look for in the speci-
fication if § 112(f) applies, id. at 1233, but also to determine
whether § 112(f) applies in the first place. The search for
corresponding structure and the determination whether
§ 112(f) applies, though “distinct,” are “inherently related.”
Apple Inc. v. Motorola, Inc., 757 F.3d 1286, 1296 (Fed. Cir.
2014). The identity of a claimed function logically bears on
whether the claim recites enough structure to avoid
§ 112(f), because that part of the inquiry asks whether the
relevant non-function term in the claim identifies “suffi-
cient structure for performing [the claimed] function,” Wil-
liamson, 792 F.3d at 1348 (citation omitted). See also
Egenera, 972 F.3d at 1374 (rejecting idea that “any” or
“some” structure, divorced from claimed functions, was suf-
ficient); Dyfan, 28 F.4th at 1368 (looking to “availability of
off-the-shelf code to perform the recited claim functions” to
determine that term “code” was not governed by § 112 ¶ 6
(emphasis added)).
Whether the non-function term (here, “executable pro-
gram code”) identifies sufficient structure has two aspects
that are of particular importance for the present case.
First: We have often asked whether the non-function term
would be understood by relevant artisans to name some-
thing identified by structural (not just functional) proper-
ties at all (a necessary predicate to being a structure that
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 16
suffices for the claimed function(s)). Dyfan, 28 F.4th at
1365–66; Williamson, 792 F.3d at 1348, 1351. The non-
function term (a word or group of words) may identify
structure because the term is “generally known in the art”
as the name for structure. Apple, 757 F.3d at 1299; see Wil-
liamson, 792 F.3d at 1348, 1351. Accordingly, “a critical
question is whether ‘the claim term is used in common par-
lance or by persons of skill in the pertinent art to designate
structure.’” MTD Products, 933 F.3d at 1341 (quoting
Skky, Inc v. MindGeek, s.a.r.l., 859 F.3d 1014, 1019 (Fed.
Cir. 2017)); see, e.g., Rembrandt Data Technologies, LP
v. AOL, LLC, 641 F.3d 1331, 1341 (Fed. Cir. 2011) (“frac-
tional rate encoding means” not a means-plus-function
term because “self-descriptive” to relevant artisan and
“used in publications and published patents”). That can be
so, we have recognized, even if the name was derived from
or reflects a function. Lighting World, Inc v. Birchwood
Lighting, Inc., 382 F.3d 1354, 1359–60 (Fed. Cir. 2004); see,
e.g., Greenberg v. Ethicon Endo-Surgery, Inc., 91 F.3d
1580, 1583 (Fed. Cir. 1996) (construing “detent mecha-
nism” as not governed by § 112 ¶ 6 and comparing terms
like “screwdriver” and “container”); Rembrandt, 641 F.3d
at 1341 (“fractional rate encoding means”); Personalized
Media Communications, LLC v. International Trade Com-
mission, 161 F.3d 696, 704–05 (Fed. Cir. 1998) (“detector”).
Similarly, a claim term need not “call to mind a single well-
defined structure” as long as it is “reasonably well under-
stood” to refer to a class of structures identified by some-
thing beyond its function of producing a general result.
Greenberg, 91 F.3d at 1583; Apple, 757 F.3d at 1300.
Second: Not just extra-patent usage in the field on its
own, but, consistent with the importance of context to claim
construction generally, the claim language may suffice to
make clear whether certain claim words name sufficient
structure in the understanding of the relevant artisan.
Thus, we have recognized that even if a non-function term
would be non-structural “in a vacuum,” surrounding claim
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 17
language can establish that the non-function term is un-
derstood by a relevant artisan as having a particular struc-
ture. Dyfan, 28 F.4th at 1370; see MTD Products, 933 F.3d
at 1341–42; TEK Global, S.R.L. v. Sealant Systems Inter-
national, Inc., 920 F.3d 777, 785–86 (Fed. Cir. 2019); Zero-
click, LLC v. Apple Inc., 891 F.3d 1003, 1008 (Fed. Cir.
2018); Inventio, 649 F.3d at 1358–59; Linear Technology
Corp. v. Impala Linear Corp, 379 F.3d 1311, 1320 (Fed. Cir.
2004); see also Apple, 757 F.3d at 1299–301 (explaining
that a specification may define a claim term). In a phrase
referring to a computer process, this may occur where the
claim makes clear (expressly or implicitly) that the non-
function term calls for a particular “operation,” which “is
more than just its function; it is how the function is
achieved in the context of the invention.” Apple, 757 F.3d
at 1299; see also Dyfan, 28 F.4th at 1366 (quoting Apple,
757 F.3d at 1299); Inventio, 649 F.3d at 1358.
The function-operation distinction warrants particular
attention in the software context, which is at issue here,
because a non-functional term referring to code “is partly
defined by its function.” Dyfan, 28 F.4th at 1368. Con-
sistent with the required structure/function statutory dis-
tinction, our cases reflect the significance in this context of
the degree of generality of the claimed “function(s)” and the
presence or absence in the claim of what relevant artisans
would understand to disclose “how” the function is per-
formed, going beyond calling for a functional result. Com-
pare Egenera, 972 F.3d at 1374–75 (holding “logic to
modify” governed by § 112(f) where there was “no struc-
tural limitation to the ‘inputs, outputs, connections, and
operation’”), and Robert Bosch, 769 F.3d at 1099–100 (hold-
ing § 112(f) applicable to term “device” where function was
highly general (“program recognition”), claim “d[id] noth-
ing more than identify functions for the ‘device’ to perform,”
and specification was “silent about any interaction between
the ‘program recognition device’ and other components”),
and Williamson, 792 F.3d at 1351 (holding “distributed
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learning control module” subject to § 112 ¶ 6 where “cer-
tain inputs and outputs” were described only at “a very
high level” and claim lacked description of “interact[ion]
with other components . . . that might inform the struc-
tural character of the limitation”), with Apple, 757 F.3d at
1301 (holding that term “heuristic” was not governed by
§ 112 ¶ 6 where the “claim language and specification dis-
close[d] the heuristics’ operation within the context of the
invention, including the inputs, outputs, and how certain
outputs are achieved”), and Dyfan, 28 F.4th at 1367–68
(holding term “code” not subject to § 112(f) “when coupled
with language describing its operation,” e.g., claimed steps
of detecting movement, receiving information, and display-
ing information, which “connotes structure”).
2
Our body of case law implementing the structure/func-
tion principle built into § 112(f), especially as illuminated
by Dyfan, calls for analysis of this case that goes beyond
what has already been done by the parties and the district
court as the case comes to us. It is true, as the district court
said, that a “definition of ‘executable program’” to mean a
“‘program that is ready to run on a given computer’ . . .
gives no indication that ‘executable program code’ is a spe-
cific code with definite structure.” Claim Construction Or-
der, at *5–6. It is also true that even if the “executable
program code” limitations refer to “logic,” the term “logic”
“[b]y itself” is similarly unstructured and generic. Id., at
*6. But additional analysis is needed.
Further attention to the character of the claimed func-
tions is required for a sound determination whether the
claims’ recitation of annotation or synchronous-play func-
tionality (though on their face seemingly more about user-
desired results than technological means to achieve them)
provides adequate structure even if “executable program
code” standing alone does not. See Dyfan, 28 F.4th at
1368–69 (stressing need to “[r]eview[ ] the alleged means-
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 19
plus-function limitation in full” and analyze whether “the
recitation of the code[’s] . . . operation would have connoted
structure to” relevant artisans (emphases added)). In ad-
dition, although expert declarations were submitted, they
may not have been focused on the full scope of the issue,
and in any event, the district court did not find facts based
on that evidence. See Claim Construction Order, at *5
(mentioning expert evidence only in passing). Instead, it
appears that the district court resolved the issue on the in-
trinsic record, but without conducting the inquiry into ex-
tra-patent usage that can be essential to determining
whether an alleged means-plus-function phrase, including
the recitation of the claimed function, names or describes
at least a class of structures sufficient to perform the func-
tion. See Dyfan, 28 F.4th at 1366–68.
Amazon urges us to uphold the district court’s decision,
citing Robert Bosch and Egenera, but there is more analysis
to be done for how those decisions, together with Dyfan,
properly apply here. In Robert Bosch, we determined that
the term “program recognition device” was subject to § 112
¶ 6 because, looking to both the claim language and the
specification, the claim “d[id] nothing more than identify
functions for the ‘device’ to perform.” 769 F.3d at 1099–100
(emphasis added); see id. at 1099 (“[A]ll of the proffered ci-
tations from the specification merely explain [the term’s]
function.” (emphasis added)). In Egenera, we focused on
whether there was recited structure for “the claimed func-
tions,” rejecting the idea that the term “logic” was not sub-
ject to § 112(f) simply because it denoted “some possible
structure” in the form of “software, firmware, or circuitry.”
972 F.3d at 1374.
TrackTime does not argue that the phrase “executable
program code” avoids § 112(f) because it connotes any
structure at all, but that the recitation of “‘executable pro-
gram code’ that is ‘configured’ to perform specific opera-
tions” would be understood, “read as a whole, to refer to
‘well-understood’ code for performing those operations.”
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TrackTime Opening Br. at 20; J.A. 1386–87, 1389–91,
1400–03 (arguing same to district court). It provided ex-
amples from the prior art that, according to TrackTime,
would have been understood to be the referred-to structure.
E.g., J.A. 1636. That argument may well be wrong, but the
district court should have explained why the pertinent ev-
idence requires the conclusion that a relevant artisan
would not so understand the disputed terms before holding
that § 112(f) applies. Accordingly, we vacate the determi-
nation that the “executable program code” terms are inva-
lid for indefiniteness.
On remand, the focus of the § 112(f) analysis should be
on whether the disputed limitations, read in full and in con-
text, recite enough structure to perform the claimed func-
tions. See Dyfan, 28 F.4th at 1368–69; Williamson, 792
F.3d at 1348. Here, the relevant claimed functions are an-
notation and synchronous play (1) on a mobile computing
device and (2) integrable with the other functionality de-
scribed in the claims.4 That the code runs on a mobile de-
vice is the natural import of the claims’ references to
“mobile computing device software.” ’978 patent, col. 64,
lines 47–51 (annotation function); col. 64, lines 54–57 (syn-
chronous-play function). And the ordinary meaning of a
claim to a single element having multiple features is that
a single instance of the element must meet each limitation.
See In re Varma, 816 F.3d 1352, 1363 (Fed. Cir. 2016) (“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 claim language that
4 We note that, because the asserted ’978 claims all
incorporate claim 1’s disputed annotation limitation, it
would not be necessary to reach the synchronous-play lim-
itation were the district court to again decide on remand
that the annotation limitation is an indefinite means-plus-
function term.
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 21
here requires the annotation, synchronous-play, and other
functions to be carried out by the same “software” com-
municates that the code referred to must be capable of be-
ing implemented with code that performs the other claimed
functions. Our reading of the claim language is confirmed
by the specification, because mobile-device implementation
and integrability are the key assertedly inventive features
of the disclosure; the specification distinguishes prior-art
software “unsuitable for mobile computing devices,” assert-
ing that mobile computing devices “cannot run [certain ex-
isting] transcript management utilities,” id., col. 1, lines
55–58, and purports to solve the problem of “disparate soft-
ware applications,” id., col. 8, lines 15–22; see id., col. 11,
lines 46–50.
The parties’ arguments to date have not been focused
on whether the claims reveal structure for those precise
functions. In light of that fact, and of the foregoing elabo-
ration of the required § 112(f) analysis, it may be appropri-
ate and helpful to the court for the parties to have a new
opportunity to present arguments and evidence directed to
the correct questions. We leave that determination to the
district court’s sound discretion, but, however the court
proceeds, certain aspects of the record appear to warrant
closer attention now that the relevant functions have been
pinpointed.
The ’978 patent’s claims, taken alone, do not recite a
description of the code’s operations sufficient to define
structure. For claim 1’s annotation function, mere “user
input” is recited, ’978 patent, col. 64, line 50, and for claim
2’s synchronous-play function, not even that much is pre-
sent. See Egenera, 972 F.3d at 1374 (inquiring whether the
claims provide structure by describing “inputs, outputs,
connections, and operation” of “logic”). But the specifica-
tion requires more attention, to consider passages that pro-
vide some details, see, e.g., ’978 patent, col. 33, lines 11–12;
col. 33, lines 21–32; col. 33, lines 47–50; col. 34, lines 44–
46; col. 34, lines 60–62, and whether such details are
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 22
properly understood to limit the meaning of the claim lan-
guage at issue.
Additionally, more attention must be paid to whether
the “executable program code” limitations, for the functions
stated above, were generally known in the art at the time
of the invention as names for known code. See Williamson,
792 F.3d at 1348. Extrinsic evidence may be particularly
useful in determining whether that is so, if it is placed in
dispute. See Inventio, 649 F.3d at 1357; Dyfan, 28 F.4th at
1366. But we do not read the existing expert evidence to
which the parties refer us as directly addressing the ques-
tion. See J.A. 1478 (Schonfeld declaration, opining on bare
terms “executable” and “program code”); J.A. 1635–38
(Agrawala declaration, identifying examples of code for an-
notation but not stating whether identified code is mobile
device software); J.A. 1640–44 (similar for synchronous-
play code). We also cannot exclude the possibility that ei-
ther “executable program code” limitation might yet be
held on the intrinsic evidence alone to be a means-plus-
function term. It has, for example, been intimated in this
court (though hardly explained) that either the specifica-
tion or the prosecution history of the ’978 patent disclaims
the prior art code that TrackTime points to as the suffi-
ciently identified structure. See Amazon Br. at 56, 61; Oral
Arg. at 12:42–13:31 (Amazon’s counsel arguing that speci-
fication demonstrates that “[claimed] mobile computing de-
vice software did not exist”), https://www.cafc.us
courts.gov/oral-arguments/24-1102_05082026.mp3. If the
district court, after considering the relevant intrinsic evi-
dence, determines that it is not necessary to reach extrinsic
sources, it should explain why the intrinsic record resolves
the § 112(f) question to the degree of clarity required. See,
e.g., Williamson, 792 F.3d at 1351 (reasoning that a “fact
[attested in an expert declaration] cannot create structure
where none otherwise is disclosed [by the claims]”); Diebold
Nixdorf, Inc. v. International Trade Commission, 899 F.3d
1291, 1299–300 (Fed. Cir. 2018) (explaining that “in
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 23
appropriate cases, a party advocating [for a § 112(f) con-
struction] can overcome the presumption against its appli-
cation solely by reference to evidence intrinsic to the
patent”).
B
1
Regarding the ’638 patent, TrackTime contends that it
was entitled to judgment as a matter of law that Amazon
infringes claim 9 because there was insufficient evidence to
find otherwise. TrackTime Opening Br. at 25–51. The
jury’s special verdict provides six independent bases for the
determination that Amazon is not liable for infringement.
See J.A. 5378–83. We focus on only one ground, anticipa-
tion of claim 9 by LiveNote, for which we determine the
record contains sufficient support. It is therefore unneces-
sary for us to decide the merits of TrackTime’s remaining
arguments for reversing the denial of JMOL.
TrackTime argues that there was insufficient evidence
for the jury to find that LiveNote anticipates ’638 claim 9
because (1) LiveNote does not disclose “performing a data
lookup”; (2) LiveNote does not disclose the claimed “mobile
computing device”; and (3) LiveNote does not disclose a
“touch-sensitive input interface,” which TrackTime says
requires sensitivity to “human touch gestures.” TrackTime
Opening Br. at 44–46. These arguments are without merit.
TrackTime wholly fails to explain why the jury was not
permitted to find that LiveNote discloses performing a data
lookup. Moreover, that argument was not presented to the
district court, see J.A. 6643–44; JMOL Decision, at *7–8, so
TrackTime has forfeited it. See Fresenius USA, Inc. v. Bax-
ter International, Inc., 582 F.3d 1288, 1295–96 (Fed. Cir.
2009).
As for the “mobile computing device” limitation, the
LiveNote user guide expressly discloses using the program
on a “tablet PC,” J.A. 8762, 8906, which is one example
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given by the ’638 patent itself of a “mobile computing de-
vice,” ’638 patent, col. 18, lines 19–21 (“[T]he term mobile
computing device may be used interchangeably with the
term tablet computer[.]”); see id., col. 12, line 18; col. 18,
line 4. TrackTime’s understanding of the LiveNote tablet
disclosure as relating only to an annotation function, and
not to navigating a transcript using a mobile device, is
merely one possible interpretation of the evidence, and
TrackTime cites nothing in the LiveNote exhibits that says
that less than the full suite of the program’s features is
available on tablet PCs to support its position. See Track-
Time Opening Br. at 45–46 (citing only Dr. Agrawala’s tes-
timony, J.A. 6377–78, for this understanding).
TrackTime’s interpretation was also contradicted by
Dr. Schonfeld’s testimony, which the jury was permitted to
credit. J.A. 6145 (“You can use LiveNote . . . with some-
thing called a tablet PC . . . [and] the [user guide] makes
clear that you can tap on the tablet . . . instead of click-
ing[.]”); see J.A. 6145–46, 6151, 6321–22. The LiveNote
user guide’s tablet-computer disclosure and the testimony
of Amazon’s expert were sufficient evidence from which a
jury could reasonably find that LiveNote discloses the
claimed mobile computing device.
Regarding the “touch-sensitive input interface” limita-
tion, the LiveNote user guide expressly discloses using a
tablet pen for some of the program’s functionality, J.A.
8762, 8906, and the jury heard expert testimony that all of
LiveNote’s disclosures would thus have been understood by
a relevant artisan to be operable on a touchscreen device
“with a pen or a finger,” J.A. 6148–49; see J.A.6151, 6321–
22. There is therefore no merit to TrackTime’s contention
that LiveNote does not disclose transcript navigation by
human touch gestures; the jury was entitled to credit
Dr. Schonfeld’s contrary testimony. Moreover, TrackTime
did not seek a construction that would limit the claimed
“touch-sensitive input interface” to human touch, see Claim
Construction Order, at *1, and the jury could reasonably
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TRACKTIME, LLC v. AMAZON. COM SERVICES LLC 25
find that LiveNote’s express disclosure of an interface op-
erable with a tablet pen comes within the ordinary mean-
ing of “touch-sensitive input interface.” See Akamai
Technologies, Inc. v. MediaPointe, Inc., 159 F.4th 1370,
1380 (Fed. Cir. 2025). For these reasons there was suffi-
cient evidence to find that LiveNote discloses claim 9’s
touch-sensitive input interface. We therefore uphold the
finding of anticipation by LiveNote, and that is enough to
reject TrackTime’s challenge to the denial of JMOL.
2
TrackTime also argues in the alternative that, even if
it was not entitled to JMOL, the jury’s finding of anticipa-
tion by LiveNote was contrary to the “clear weight of the
evidence” such that TrackTime should have been granted
a new trial. TrackTime Opening Br. at 55. We do not
agree.
The Third Circuit will find an abuse of discretion in re-
fusing to grant a new trial when a verdict “cries out to be
overturned” or “shocks [the] conscience.” Leonard
v. Stemtech International Inc, 834 F.3d 376, 386 (3d Cir.
2016) (citations omitted). TrackTime’s arguments on this
score consist of a single sentence citing the same testimony
of Dr. Agrawala that is the basis of TrackTime’s JMOL
challenge with respect to anticipation by LiveNote. The
LiveNote user guide alone provides significant support for
the jury’s anticipation verdict, because its disclosures of
tablet PCs, without disclosing that the program’s function-
ality is in any way constrained when run on a tablet,
strongly imply that all of the manual’s disclosures apply
equally to tablet PCs. See J.A. 8762, 8906. And Dr. Schon-
feld testified to the same effect. J.A. 6145–46. TrackTime
thus, at most, identifies a run-of-the-mill contest between
experts that was within the competence of the jury to re-
solve. The district court did not abuse its discretion in de-
termining that such evidence does not show that the
verdict was so deeply flawed that a new trial was
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warranted. See Leonard, 834 F.3d at 386. We thus affirm
the district court’s denial of a new trial. TrackTime’s other
arguments for a new trial do not implicate the anticipation
ground on which we affirm the denial of judgment as a mat-
ter of law, so we need not and do not reach them.
III
We have considered the parties’ remaining arguments
and find them unpersuasive. For the foregoing reasons, we
vacate the district court’s judgment of invalidity of the as-
serted claims of the ’978 patent and remand for further pro-
ceedings consistent with this opinion. As to the ’638
patent, we affirm the district court’s denial of JMOL and
its refusal to grant a new trial.
The parties shall bear their own costs.
AFFIRMED IN PART, VACATED IN PART, AND
REMANDED
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