United States Court of Appeals
for the Federal Circuit
__________________________
INVENTIO AG,
Plaintiff-Appellant,
v.
THYSSENKRUPP ELEVATOR AMERICAS
CORPORATION, THYSSENKRUPP ELEVATOR
CORPORATION, AND THYSSENKRUPP ELEVATOR
MANUFACTURING INCORPORATED,
Defendants-Appellees.
__________________________
2010-1525
__________________________
Appeal from the United States District Court for the
District of Delaware in Case No. 08-CV-0874, Judge
Eduardo C. Robreno.
____________________________
Decided: June 15, 2011
____________________________
PIERRE R. YANNEY, Stroock & Stroock & Lavan LLP,
of New York, New York, argued for plaintiff-appellant.
DAVID E. SCHMIT, Frost Brown Todd LLC, of Cincin-
nati, Ohio, argued for defendants-appellees.
__________________________
Before LOURIE, PROST, and MOORE, Circuit Judges.
INVENTIO AG v. THYSSENKRUPP 2
LOURIE, Circuit Judge.
Inventio AG (“Inventio”) appeals from the final judg-
ment of the United States District Court for the District of
Delaware in favor of ThyssenKrupp Elevator Americas
Corporation, ThyssenKrupp Elevator Corporation, and
ThyssenKrupp Elevator Manufacturing Incorporated
(collectively, “ThyssenKrupp”). See Inventio AG v.
ThyssenKrupp Elevator Americas Corp., No. 1:08-CV-874,
Judgment (ECF No. 164) (D. Del. Aug. 4, 2010) (“Final
Judgment”). The judgment follows the district court’s
granting of ThyssenKrupp’s motion for summary judg-
ment that the asserted claims of U.S. Patents 6,892,861
(“the ’861 patent”) and 6,935,465 (“the ’465 patent”) are
invalid for failure to meet the definiteness requirement of
35 U.S.C. § 112, ¶ 2. See Inventio AG v. ThyssenKrupp
Elevator Americas Corp., No. 1:08-CV-874, Order (ECF
No. 163) (D. Del. Aug. 4, 2010) (“SJ Order”). The district
court entered summary judgment after concluding that
the claimed “modernizing device” and “computing unit”
limitations were means-plus-function limitations subject
to 35 U.S.C. § 112, ¶ 6 and that the written descriptions
failed to disclose any corresponding structure. See Inven-
tio AG v. ThyssenKrupp Elevator Americas Corp., No.
1:08-CV-874, Order (ECF No. 162) (D. Del. Aug. 4, 2010)
(“Order on Motion for Reargument”); Inventio AG v.
ThyssenKrupp Elevator Americas Corp., 718 F. Supp. 2d
529, 542–556, 558–561 (D. Del. 2010) (“Claim Construc-
tion Opinion”). Because the district court erred when it
concluded that the “modernizing device” and “computing
unit” terms were means-plus-function limitations subject
to § 112, ¶ 6, we reverse and remand for further proceed-
ings.
3 INVENTIO AG v. THYSSENKRUPP
ORDER ON MOTION TO STRIKE
Before we discuss the merits of Inventio’s appeal, we
address ThyssenKrupp’s motion to strike. After the
parties submitted their briefs, ThyssenKrupp filed a
motion to strike portions of Inventio’s reply brief, arguing
that it contained new and seriously misleading arguments
about the disclosure of the ’861 and ’465 patents, mis-
characterized legal precedent, misrepresented ThyssenK-
rupp’s responsive brief, and misrepresented the record in
this case.
ThyssenKrupp’s motion lacks merit. It reargues the
merits of the case. ThyssenKrupp simply disagrees with
Inventio’s legal arguments, and its motion seems to us to
be an improper attempt to obtain the final word in the
appeal, a practice that we strongly discourage. See
Aventis Pharma S.A. v. Hospira, Inc., 637 F.3d 1341,
1343–44 (Fed. Cir. 2011). Its nasty tone is exemplified by
use of the word “blatantly” or “blatant” at least four times.
Thus, ThyssenKrupp’s filing of this motion borders on the
type of frivolous and wasteful litigation tactics that we
have previously frowned upon. See Otocom Sys., Inc. v.
Houston Computer Servs., Inc., 918 F.2d 937, 943–44
(Fed. Cir. 1990). We accordingly deny ThyssenKrupp’s
motion and turn to the merits of Inventio’s appeal.
BACKGROUND
This patent case relates to elevator systems. In gen-
eral terms, the asserted patents involve “modernizing” a
conventional elevator system. ’861 patent col.1 ll.6–7. 1 In
a conventional elevator system, a passenger, at the board-
ing floor, presses the “up/down” buttons on a floor call
1 Because the ’861 and ’465 patents contain a com-
mon disclosure for the issues presented in this appeal, we
will cite the ’861 patent for simplicity.
INVENTIO AG v. THYSSENKRUPP 4
transmitter, which causes a signal, referred to as a “call
report,” to be sent to the elevator control. Id. col.4 ll.64–
67. The elevator control is the hardware that drives the
elevator system to transport elevator cars between floors.
Id. col.4 ll.16–37. The call report, which is generally an
analog voltage signal, indicates to the elevator control the
passenger’s boarding floor and may also indicate in which
direction the passenger desires to travel (up or down). Id.
col.4 ll.64–67, col.5 ll.37–40. After receiving this signal,
the elevator control dispatches an elevator car to the
passenger’s floor. Id. col.5 ll.43–49. Once inside the
elevator car, the passenger selects a floor, which sends a
second call report to the elevator control and causes the
elevator system to transport the passenger to the destina-
tion floor. Id. col.5 ll.51–58.
The asserted patents disclose a modernized elevator
system and a process for modernization. The modernized
elevator system allows a passenger, at the boarding floor,
to enter the passenger’s desired destination. Id. col.2 ll.4–
18. As part of the modernization process, new floor ter-
minals replace the original floor call transmitters (i.e., the
“up/down” buttons), and the new floor terminals allow a
passenger, at the boarding floor, to input a desired desti-
nation floor when requesting an elevator. Id. col.6 ll.3–19.
The patents also disclose the back-end technology that
interfaces with the new floor terminals and the conven-
tional elevator control to operate the modernized elevator
system, and this appeal focuses on those aspects of the
modernized elevator system. In particular, the patents
disclose a “modernizing device” and a “computing unit”
that interface with the new floor terminals and the eleva-
tor control to operate the elevator system. Id. col.2 ll.28–
53. Claim 1 of the ’465 patent, reproduced below, is
representative of the claims on appeal and claims the
5 INVENTIO AG v. THYSSENKRUPP
method of installing these components to modernize a
conventional elevator system:
1. A method of modernizing an elevator installa-
tion having at least one elevator controlled by
at least one elevator control by way of at least
one call report, comprising:
a. installing at least one floor terminal at each
floor served by an elevator controlled by an
elevator control for at least one of the input of
destination call reports and for recognition of
identification codes of users;
b. installing at least one computing unit and con-
necting the at least one computing unit to said
floor terminals for at least one of evaluating
the destination call reports and association of
destination floors with recognized ones of the
identification codes, and for the output of at
least one destination signal; and
c. installing at least one modernizing device and
connecting the at least one modernizing device
to said floor terminals and said at least one
computing unit for reading the destination
signal, for converting the destination signal
into at least one call report and for controlling
the elevator control by way of the call report.
’465 patent, col.11 ll.6–25 (emphases added). The written
descriptions of both patents also show how the “comput-
ing unit” and the internal components of the “modernizing
device” are connected to each other and the elevator
control:
INVENTIO AG v. THYSSENKRUPP 6
As shown in the above figure, the modernizing device
may communicate with both the computing unit and the
elevator control. The modernizing device may receive
digital transmissions from the computing unit and con-
vert them into call reports issued to the elevator control.
Id. col.7 ll.49–60. In addition to converting the digital
signal into a call report, the modernizing device is also
capable of receiving call reports and converting them into
a digital form for processing, either by the modernizing
device or the computing unit. Id. col.8, ll.54–65, col.9,
ll.34–67.
The written descriptions explain how the modernized
elevator system functions during operation. First, a
passenger at the boarding floor inputs a destination floor
to the new floor terminals by manually entering informa-
tion or providing an identification code to a recognition
device. Id. col.8 ll.8–14. The computing unit, which is
connected to the terminals, receives the boarding floor
and destination floor information and executes a “com-
7 INVENTIO AG v. THYSSENKRUPP
puter program product” to determine, based on that
information and other data, the optimal use of the eleva-
tor cars to transport the passenger to the desired floor.
Id. col.6 l.27–col.7 l.25, col.8 ll.15–23. The computer
program product performs the calculation by executing a
“destination dispatch algorithm.” Id. col.6 l.27–col.7 l.25.
The computing unit then generates a control signal,
which includes a series of destination signals, as a result
of the optimization calculation. Id. col.8 ll.21–24. The
modernizing device receives the first destination signal,
converts this digital signal into an analog call report, and
transmits the call report to the elevator control. Id. col.8
ll.21–40. The elevator control subsequently processes the
call report and controls the elevator machinery to move
the elevator car to the boarding floor. Id. col.8 ll.37–40.
After the passenger has boarded the elevator car, the
modernizing device receives a second destination signal
from the computing unit. Id. col.8 ll.41–45. The modern-
izing device, after receiving this signal, converts the
signal into an analog call report, and transmits the call
report to the elevator control. Id. col.8 ll.42–51. In accor-
dance with the second call report, the elevator control
causes the elevator car to move from the boarding floor to
the destination floor. Id.
In 2008, Inventio sued ThyssenKrupp in the District
of Delaware, alleging infringement of various claims of
the ’465 and ’681 patents. After holding a Markman
hearing, the district court construed numerous claim
terms. During the claim construction process, the district
court concluded that the terms “modernizing device” and
“computing unit” were indefinite.
In reaching this conclusion, the district court first
concluded that both terms lacked sufficiently definite
structure to avoid § 112, ¶ 6. With regard to the “modern-
INVENTIO AG v. THYSSENKRUPP 8
izing device,” the court concluded that while the term was
presumptively not a means-plus-function limitation, the
claim language failed to recite corresponding structure to
perform the “modernizing” function. Claim Construction
Opinion, 718 F. Supp. 2d at 542–43. For the “computing
unit” terms, the court similarly concluded that the claim
language, although presumptively not a means-plus-
function limitation, failed to provide corresponding struc-
ture to perform the functions of the “computing unit.” Id.
at 559–60. After concluding that the terms were means-
plus-function limitations, the district court concluded that
both terms were indefinite because the written descrip-
tions also failed to disclose corresponding structure to
perform the recited functions. Id. at 544–46, 559–61.
The district court subsequently denied Inventio’s mo-
tion for reargument, Order on Motion for Reargument, at
1, and granted ThyssenKrupp’s motion for summary
judgment that the asserted claims were invalid for failure
to meet the definiteness requirement under § 112, ¶ 2. SJ
Order, at 1–2. The district court then entered final judg-
ment for ThyssenKrupp. Final Judgment, at 1.
Inventio timely appealed. We have jurisdiction pur-
suant to 28 U.S.C. § 1295(a)(1).
DISCUSSION
Central to this appeal is whether the terms “modern-
izing device” and “computing unit” are means-plus-
function limitations that fall within the ambit of
§ 112, ¶ 6. Because we conclude that the claimed “mod-
ernizing device” and “computing unit” are not means-plus-
function limitations, we do not address whether the
written descriptions disclose corresponding structure. We
also decline to provide constructions for these claim
terms, as the claim-scope dispute in this case focused on
whether these claim terms are subject to § 112, ¶ 6, and
9 INVENTIO AG v. THYSSENKRUPP
the parties did not develop how these terms should be
construed should § 112, ¶ 6 not apply.
I. Applicable Law
Section 112, ¶ 6 allows a patentee to express a claim
limitation as “a means or step for performing a specified
function without the recital of structure, material, or acts
in support thereof,” and the section provides that claim
limitations expressed in this manner “shall be construed
to cover the corresponding structure, material, or acts
described in the specification and equivalents thereof.”
That provision applies “only to purely functional limita-
tions that do not provide the structure that performs the
recited function.” Phillips v. AWH Corp., 415 F.3d 1303,
1311 (Fed. Cir. 2005) (en banc). Whether certain claim
language invokes § 112, ¶ 6 is an exercise in claim con-
struction and is therefore a question of law, subject to de
novo review. Personalized Media Commc’ns, LLC v. ITC,
161 F.3d 696, 702 (Fed. Cir. 1998).
The framework under which we determine if a claim
limitation invokes § 112, ¶ 6 is straightforward. The use
of the term “means” triggers a rebuttable presumption
that § 112, ¶ 6 governs the construction of the claim term.
TriMed, Inc. v. Stryker Corp., 514 F.3d 1256, 1259 (Fed.
Cir. 2008). Conversely, where, as here, the claim lan-
guage does not recite the term “means,” we presume that
the limitation does not invoke § 112, ¶ 6. Personalized
Media, 161 F.3d at 703–04. When a claim term lacks the
word “means,” the presumption can be overcome if the
challenger demonstrates that “the claim term fails to
‘recite sufficiently definite structure’ or else recites ‘func-
tion without reciting sufficient structure for performing
that function.’” CCS Fitness v. Brunswick Corp., 288 F.3d
1359, 1369 (Fed. Cir. 2002) (quoting Watts v. XL Sys.,
Inc., 232 F.3d 877, 880 (Fed. Cir. 2000)).
INVENTIO AG v. THYSSENKRUPP 10
As the above standard shows, the use of the word
“means” is central to the analysis, as the terms “means”
and “means for” have become closely associated with
means-plus-function claiming. See Lighting World, Inc. v.
Birchwood Lighting, Inc., 382 F.3d 1354, 1358 (Fed. Cir.
2004). Thus, the presumption flowing from the absence of
the term “means” is a strong one that is not readily over-
come. Id.
At the outset, the parties dispute whether the “suffi-
ciently definite structure” analysis focuses on the claim
language in isolation or allows the court to view the claim
language in light of the written description to determine if
ThyssenKrupp has rebutted the presumption that the
claims recite sufficiently definite structure. Quoting
TriMed, ThyssenKrupp argues that the “sufficiently
definite structure” analysis hinges on whether the claim
language “specifies the exact structure that performs the
functions in question without need to resort to other
portions of the specification or extrinsic evidence for an
adequate understanding of the structure.” 514 F.3d at
1259–60. Relying primarily on Personalized Media,
Inventio argues that, to determine if a claim term that
lacks the word “means” is subject to § 112, ¶ 6, the court
should consider the intrinsic record.
We agree with Inventio. Claims are interpreted in
light of the written description supporting them, and that
is true whether or not the claim construction involves
interpreting a “means” clause. The presumption that a
claim lacking the term “means” recites sufficiently defi-
nite structure can be rebutted “if the evidence intrinsic to
the patent and any relevant extrinsic evidence so war-
rant[s].” Personalized Media, 161 F.3d at 704. In decid-
ing whether a challenger has rebutted the presumption,
“the focus remains on whether the claim as properly
construed recites sufficiently definite structure to avoid
11 INVENTIO AG v. THYSSENKRUPP
the ambit of § 112, ¶ 6.” Id. To determine the proper
construction of a claim term, we look to the words of the
claims themselves, the written description, the prosecu-
tion history, and any relevant extrinsic evidence. Phil-
lips, 415 F.3d at 1315–17. In addition, we allow an
inventor to provide, in the written description, express
definitions for terms that appear in the claims, and those
definitions govern the construction of the claims. Id. at
1316.
In cases where the claims do not recite the term
“means,” considering intrinsic and extrinsic evidence is
usually helpful, as the litigated issue often reduces to
whether skilled artisans, after reading the patent, would
conclude that a claim limitation is so devoid of structure
that the drafter constructively engaged in means-plus-
function claiming. See MIT v. Abacus Software, 462 F.3d
1344, 1354 (Fed. Cir. 2006). Indeed, in prior cases, we
have reviewed the intrinsic record, as well as extrinsic
evidence such as technical dictionaries, to determine if the
challenger successfully rebutted the presumption that a
claim that lacks the term “means” is not subject to
§ 112, ¶ 6. E.g., Phillips, 415 F.3d at 1311 (concluding
that term “steel baffles” was not a means-plus-function
limitation where “[t]he claims and the specification un-
mistakably establish that the ‘steel baffles’ refer to par-
ticular physical apparatus”); Personalized Media, 161
F.3d at 704 (declining to construe “digital detector” as a
means-plus-function limitation where “neither intrinsic
nor extrinsic evidence” rebutted the presumption that a
“detector” connoted structure to those of skill in the art);
Lighting World, 382 F.3d at 1360–63 (reviewing the
written description, technical dictionaries, and expert
testimony to conclude that the defendant failed to rebut
the presumption that the claimed “connector assembly”
connoted sufficiently definite structure).
INVENTIO AG v. THYSSENKRUPP 12
In light of this caselaw, ThyssenKrupp’s reading of
TriMed misses the mark. While it is true that the claim
language, in order to avoid the application of § 112, ¶ 6
when a claim recites the term “means,” must “specif[y]
the exact structure that performs the functions in ques-
tion,” TriMed, 514 F.3d at 1259–60, TriMed does not
preclude consideration of the written description, prosecu-
tion history, and extrinsic evidence to determine if a
challenger has rebutted the presumption that a claim
limitation that lacks the term “means” connotes suffi-
ciently definite structure to those of skill in the art.
Moreover, where the claims recite the term “means,” we
have considered the written description to inform the
analysis of whether the claim recites sufficiently definite
structure to overcome the presumption that § 112, ¶ 6
governs the construction of the claim. See e.g., TI Grp.
Automotive Sys. (N. Am.), Inc. v. VDO N. Am., L.L.C., 375
F.3d 1126, 1135 (Fed. Cir. 2004) (concluding that
§ 112, ¶ 6 did not apply to recited “pumping means” where
“[t]he written description informs and fully supports the
structure recited in the claims”). Accordingly, it is proper
to consult the intrinsic record, including the written
description, when determining if a challenger has rebut-
ted the presumption that a claim lacking the term
“means” recites sufficiently definite structure.
II. Modernizing Device
Inventio argues that the district court erred when it
concluded that the claimed “modernizing device” is a
means-plus-function limitation. Inventio argues that the
claims recite structural detail about the modernizing
device and how it is connected to other components of the
patented system. In addition, Inventio argues that the
written descriptions identify the modernizing device as a
structural component, as they provide a block diagram of
13 INVENTIO AG v. THYSSENKRUPP
the modernizing device and also describe the structure
and operation of the modernizing device.
ThyssenKrupp argues that the claimed “modernizing
device” is defined only in terms of the functions that the
device performs, not its structure. ThyssenKrupp also
argues that the claims provide no physical structure for
the modernizing device, that there is no evidence that the
term “modernizing device” had a well understood meaning
in the art, and that there is no evidence that technical
dictionaries recognize a “modernizing device” as denoting
structure. Finally, citing MIT and Personalized Media,
ThyssenKrupp argues that the term “device” is a generic
term like “means” and that the modifier “modernizing”
does not add structure.
We agree with Inventio. The term “modernizing de-
vice” presumptively connotes sufficiently definite struc-
ture to those of skill in the art, Personalized Media, 161
F.3d at 703–04, and that presumption is a strong one that
is not readily overcome, Lighting World, 382 F.3d at 1358.
In this case, ThyssenKrupp has not overcome the pre-
sumption that the claimed “modernizing device” connotes
sufficiently definite structure.
In past cases, we have concluded that a claimed “cir-
cuit,” coupled with a description of the circuit’s operation
in the claims, connoted sufficiently definite structure to
skilled artisans to avoid the application of § 112, ¶ 6.
MIT, 462 F.3d at 1355–56; Linear Tech. Corp. v. Impala
Linear Corp., 379 F.3d 1311, 1320–21 (Fed. Cir. 2004);
Apex Inc. v. Raritan Comp., Inc., 325 F.3d 1364, 1374
(Fed. Cir. 2003). As we explained in Linear, the term
“circuit” itself connotes structure and the contextual
language that describes the objective and operation of the
claimed “circuit” conveys the structural arrangement of
the circuit’s components and provides additional limiting
INVENTIO AG v. THYSSENKRUPP 14
structure. 379 F.3d at 1320–21. Thus, we concluded in
Linear that a claimed “circuit” for “monitoring a signal
from the output terminal to generate a first feedback
signal” was not subject to § 112, ¶ 6 because the term
connoted structure and the contextual language described
the objective of the “circuit”—“monitoring a signal from
the output terminal”—as well as the desired output of the
“circuit”—“generat[ing] a first feedback signal.” Id.
In this case, the claims indicate that the “modernizing
device” functions as an electrical circuit that receives
signals, processes signals, and outputs signals to other
components in the patented system. For example, claim 1
of the ’861 patent recites that the “modernizing device” is
connected to an elevator control and a computing unit,
where the computing unit transmits a destination signal
to the modernizing device. ’861 patent, col.11 ll.6–21.
The modernizing device then converts that destination
signal into a call report and transmits the call report to
the elevator control. Id. In addition, dependent claims
describe the input, output, and signal receiver aspects of
the modernizing device, id. col.11 l.22–36, 44–55, and
describe the comparison of a target value or indication
signal with a plurality of travel time profiles that the
modernizing device performs, id. col.11 ll.37–43, col.12
ll.1–8. Similarly, claim 1 of the ’465 patent claims a
“modernizing device” that is connected to floor terminals
and a computing unit, where the modernizing device
reads a destination signal, converts the destination signal
into a call report, and controls the elevator control by way
of the call report. ’465 patent, col.11 ll.6–25.
The written descriptions support the conclusion that
the claimed “modernizing device” is not a purely func-
tional limitation. As detailed above, the written descrip-
tions depict the modernizing device and its internal
components, namely, the processor, signal generator,
15 INVENTIO AG v. THYSSENKRUPP
converter, memory, and signal receiver elements. ’861
patent, Fig. 3. The written descriptions also show how
the elements are connected together and to the elevator
control and computing unit components of the elevator
system. Id. They also describe how the modernizing
device, employing these components, receives a destina-
tion signal from the computing unit, converts it into a call
report, and issues the call report to the elevator control.
Id. col.7 l.49–col.8 l.4. In addition, they describe that the
modernizing device has an input and signal receiver that
detects a signal from the elevator control, such as a target
value, and processes the signal with a time travel profile
to control the elevator system. Id. col.8 l.54–col.9 l.67.
In sum, the claims and written descriptions show that
ThyssenKrupp has failed to overcome the presumption
that the claimed “modernizing device” is not a means-
plus-function limitation. In light of this disclosure,
ThyssenKrupp’s reliance on dicta in the Personalized
Media and MIT cases is unavailing. In those cases, we
stated that the term “device” was a generic structural
term that “typically do[es] not connote sufficiently definite
structure.” MIT, 462 F.3d at 1354. In this case, however,
the claims recite a “modernizing device,” delineate the
components that the modernizing device is connected to,
describe how the modernizing device interacts with those
components, and describe the processing that the modern-
izing device performs. The written descriptions addition-
ally show that the modernizing device conveys structure
to skilled artisans. Thus, this is not a case where a claim
nakedly recites a “device” and the written description fails
to place clear structural limitations on the “device.”
III. Computing Unit
Inventio also challenges the district court’s conclusion
that the claim term “computing unit” is a means-plus-
INVENTIO AG v. THYSSENKRUPP 16
function limitation. Inventio argues that a “computing
unit” connotes structure to those of skill in the art, spe-
cifically a computer or other data processing device.
Inventio also argues that the written descriptions explic-
itly define the “computing unit” as “a commercially avail-
able personal computer or a workstation,” which includes
“at least one processor and at least one data memory.”
ThyssenKrupp argues that the claimed “computing
unit” lacks sufficiently definite structure to avoid the
application of § 112, ¶ 6 because the claims fail to provide
any physical structure, the term “computing unit” lacks a
well understood meaning in the art, and the term “unit” is
the legal equivalent of “means.” ThyssenKrupp also
argues, quoting Brown v. Baylor Healthcare System, that
even if a “computing unit” is read to mean a computer,
simply disclosing “a general processor without more” is
not enough “to perform the claimed function” and avoid
the application of § 112, ¶ 6. 381 Fed. Appx. 981, 983–84
(Fed. Cir. 2010) (nonprecedential decision).
We agree with Inventio that the “computing unit”
here connotes sufficiently definite structure. Similar to
the term “modernizing device,” the claimed “computing
unit” presumptively connotes sufficiently definite struc-
ture to those of skill in the art. Personalized Media, 161
F.3d at 703–04. The claims indicate that the presumption
is not overcome in this case. The claims recite that the
computing unit is connected to the modernizing device
and generates a destination signal for transmission to the
modernizing device. ’861 patent, col.11 ll.6–21. The
claims elaborate that the computing unit is connected to
the floor terminals of the elevator system, and evaluates
incoming call reports, destination floors, and identifica-
tion codes to generate the destination signal for process-
ing by the modernizing device. Id. col.12 ll.9–52; ’465
patent, col.12 ll.7–59.
17 INVENTIO AG v. THYSSENKRUPP
The written descriptions also indicate that the “com-
puting unit” connotes structure to skilled artisans. As the
claim term implies, the written descriptions refer to the
computing unit as a computer, where one of its functions
is to store and execute a computer program product. ’861
patent, col.6 ll.21–24 (stating that the “computing unit” is
“a commercially available personal computer or work-
station” and that the “computing unit” includes “at least
one processor and at least one data memory”); id. col.9
ll.61–64 (stating that “it is entirely possible to perform the
computer program product on any computer, for example
on the computing unit of the system or on a remote
server”) (internal reference number omitted). The written
descriptions also explain the steps that the computer
program product performs, see id. col.6 l.3–col.7 l.25, as
well as the interaction between the computing unit and
modernizing device, id. col.7 ll.26–48, and the computing
unit and the floor terminals, id. col.8 ll.6–22.
In total, this disclosure shows that ThyssenKrupp has
not rebutted the presumption that the claimed “comput-
ing unit” connotes sufficiently definite structure to those
of skill in the art. In response to this evidence,
ThyssenKrupp relies on dictum from our nonprecedential
decision in Brown to argue that a computer, when
claimed, is not sufficient structure to perform the claimed
functions as a matter of law. ThyssenKrupp’s reading of
that case, however, is overly broad.
In Brown, the patentee had the burden to show that
the “portable processing means” claim limitation recited
sufficiently definite structure to perform the recited
“processing” function, and we concluded on the record in
that case that the patentee had failed to meet that bur-
den. 381 Fed. Appx. at 983–84. We rejected the pat-
entee’s argument that one would equate the “portable
processing means” with a “general purpose processor”
INVENTIO AG v. THYSSENKRUPP 18
because the argument ignored that the patentee “chose to
claim the element at issue in functional terms.” Id. We
also noted that even if the patentee’s argument were
correct, “a general purpose processor without more would
not be enough to perform the claimed function.” Id. at
984.
Contrary to ThyssenKrupp’s arguments, Brown did
not hold, as a matter of law, that a claimed “computer” is
not sufficiently definite structure to avoid the application
of § 112, ¶ 6. Indeed, we have held that a claimed “control
unit” that comprised a “CPU” and a “portioned memory
system” recited sufficiently definite structure to perform
the recited “controlling the communication unit” function.
LG Elecs., Inc. v. Bizcom Elecs., Inc., 453 F.3d 1364, 1372
(Fed. Cir. 2006), rev’d on other grounds, Quanta Com-
puter, Inc. v. LG Elecs., Inc., 553 U.S. 617 (2008). Ulti-
mately, whether claim language invokes § 112, ¶ 6
depends on how those skilled in the art would understand
the structural significance of that claim language, as-
sessed against the presumptions that flow from a drafter’s
choice to employ or not employ the term “means.” See
Personalized Media, 161 F.3d at 704.
In this case, the inventor did not draft the claims in
“means for” format, and his decision to avoid the term
“means” raises a strong presumption that the claimed
“computing unit” connotes sufficiently definite structure
to those skilled in the art. Lighting World, 382 F.3d at
1358. ThyssenKrupp had the burden to show that the
“computing unit” terms are so structurally devoid that we
should rewrite them in means-plus-function format. The
claims and the written descriptions, however, indicate
that those of skill in the art would understand a comput-
ing unit to connote sufficiently definite structure. Thus,
on this record, ThyssenKrupp has failed to meet its bur-
den.
19 INVENTIO AG v. THYSSENKRUPP
CONCLUSION
For the foregoing reasons, the judgment of the district
court is reversed and the case is remanded to the district
court for further proceedings.
REVERSED AND REMANDED