Carrum Technologies, LLC v. Ford Motor Company, Bmw of North America, LLC, Bmw Manufacturing Co., LLC,…

N OTE: This disposition is nonprecedential.
United States Court of Appeals
for the Federal Circuit
______________________
CARRUM TECHNOLOGIES, LLC,
Plaintiff-Appellant
v.
FORD MOTOR COMPANY, BMW OF NORTH
AMERICA, LLC, BMW MANUFACTURING CO.,
LLC, BAYERISCHE MOTOREN WERKE AG,
Defendants-Appellees
______________________
2024-1183, 2024-1480
______________________
Appeals from the United States District Court for the
District of Delaware in Nos. 1:18-cv-01645-RGA, 1:18-cv-
01647-RGA-SRF, Judge Richard G. Andrews.
______________________
Decided: October 15, 2025
______________________
T AYLOR J AMES K ELSON, Bartlit Beck LLP, Denver, CO,
argued for plaintiff-appellant. Also represented by
ANDREW BAAK, J OHN HUGHES ; REBECCA HORWITZ, MARK
L ESLIE L EVINE, Chicago, IL.
J USTIN WEINER , Bush Seyferth PLLC, Troy, MI, argued
for defendant-appellee Ford Motor Company. Also repre-
sented by F RANK C. CIMINO, J R., J ONATHAN L. F ALKLER ,
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CARRUM TECHNOLOGIES , LLC v. FORD MOTOR COMPANY 2
CHARLES J. MONTERIO, MEGAN S. WOODWORTH , Venable
LLP, Washington, DC.
L IONEL M. L AVENUE, Finnegan, Henderson, Farabow,
Garrett & Dunner, LLP, Reston, VA, argued for defend-
ants-appellees BMW of North America, LLC, BMW Manu-
facturing Co., LLC, Bayerische Motoren Werke AG. Also
represented by D AVID L EFCOWITZ, BRADFORD C. SCHULZ,
D EANNA SMILEY ; F ORREST ALEXANDER J ONES , J OSEPH M.
MYLES , Washington, DC; BENJAMIN AARON SAIDMAN, K ARA
ALLYSE SPECHT , Atlanta, GA.
______________________
Before L OURIE, T ARANTO, and CUNNINGHAM , Circuit
Judges.
L OURIE, Circuit Judge.
Carrum Technologies, LLC (“Carrum”) appeals from
two final judgments of the United States District Court for
the District of Delaware, which have been consolidated for
our review.1 See Carrum Techs., LLC v. Ford Motor Co.,
No. 18-cv-1647, 2023 WL 7407778 (D. Del. Nov. 9, 2023)
(“Ford Decision” or “Ford”) (granting summary judgment of
noninfringement in favor of the Ford Motor Company
(“Ford”)); Carrum Techs., LLC v. BMW of N. Am., LLC, No.
C.A. No. 18-cv-1645, 2023 WL 9744835 (D. Del. Dec. 12,
2023) (“BMW Decision” or “BMW”) (ordering claim con-
structions consistent with the Ford Decision). For the fol-
lowing reasons, we affirm.
BACKGROUND
At issue on appeal are U.S. Patents 7,512,475 (“the ’475
patent”) and 7,925,416 (“the ’416 patent”). Carrum owns
1 See ECF No. 16 (consolidating the appeals because
the sole issue on appeal from the BMW Decision overlaps
entirely with one of the two issues from the Ford Decision).
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CARRUM TECHNOLOGIES , LLC v. FORD MOTOR COMPANY 3
both patents, which share a common specification and are
generally directed to improving adaptive cruise control
(“ACC”) performance when a vehicle is in a curve. See ’475
patent, Abstract; ’416 patent, Abstract.
In October 2018, Carrum brought suit against Ford as-
serting infringement of the ’475 and ’416 patents. The par-
ties disputed the construction of “a controller” and “said
controller” in claims 10, 11, and 12 of the ’416 patent. Ford
Decision, at *3. The parties also disputed the construction
of “change in . . . vehicle lateral acceleration” in claim 5 of
the ’475 patent and claim 6 of the ’416 patent, which each
depend from independent claims 1 of their respective pa-
tents.2 Id. The exemplary claims are as follows:
1. A method of controlling a vehicle having an
adaptive cruise control system capable of control-
ling a vehicle speed and obtaining a vehicle lateral
acceleration, said method comprising the steps of:
2 For the “change” limitation, only claims 5 of the
’475 patent and 6 of the ’416 patent are at issue on appeal.
The Patent Trial and Appeal Board (“PTAB”) determined
that claim 1 of the ’416 patent and claim 1 of the ’475 pa-
tent are unpatentable during inter partes review. Unified
Pats. Inc. v. Carrum Techs., LLC, No. IPR2019-00481,
2020 WL 4004893, at *27 (P.T.A.B. July 15, 2020); BMW of
N. Am. v. Carrum Techs., LLC, No. IPR2019-00903,
2020 WL 6141354, at *9 (P.T.A.B. October 19, 2020). We
affirmed the PTAB’s Final Written Decision on claim 1 of
the ’475 patent. See BMW of N. Am., LLC v. Carrum
Techs., LLC, No. 2021-1435, 2022 WL 378667 (Fed. Cir.
Feb. 8, 2022). The Final Written Decision on claim 1 of the
’416 patent was not appealed. See Carrum Techs., LLC v.
Unified Pats., LLC, No. 2020-2204, 2021 WL 3574209, at
*2 (Fed. Cir. Aug. 13, 2021) (stating that claim 1 was not
at issue in the appeal).
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CARRUM TECHNOLOGIES , LLC v. FORD MOTOR COMPANY 4
measuring a lateral acceleration from a lateral ac-
celeration sensor;
detecting a change in a vehicle lateral acceleration
based on a change in the measured lateral acceler-
ation;
determining when the vehicle is in a turn based on
the detected change in the vehicle lateral accelera-
tion; and
if a vehicle is in a turn, reducing the vehicle speed
according to the determination that the vehicle is
in the turn and the detected change in the vehicle
lateral acceleration.
’475 patent col. 8 ll. 7–19 (disputed terms emphasized).
5. The method of claim 1 wherein said step of re-
ducing the vehicle speed includes a step of reducing
the speed if the vehicle lateral acceleration exceeds
a predetermined limit.
Id. at col. 8 ll. 32–34.
1. A method of controlling a vehicle having an
adaptive cruise control system capable of obtaining
a vehicle lateral acceleration, said method compris-
ing the steps of:
determining when the vehicle is in a turn based on
a detected change in the vehicle lateral accelera-
tion;
determining a vehicle path during the turn;
detecting an object;
determining whether the object is in the vehicle
path during the turn;
reducing the vehicle speed if the object is deter-
mined to be in the vehicle path during the turn; and
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CARRUM TECHNOLOGIES , LLC v. FORD MOTOR COMPANY 5
ignoring the object for braking purposes if the ob-
ject is determined not to be in the vehicle path dur-
ing the turn.
’416 patent col. 8 ll. 7–19 (disputed terms emphasized).
6. The method of claim 1, wherein said step of re-
ducing the vehicle speed includes a step of reducing
the speed when the vehicle lateral acceleration ex-
ceeds a predetermined limit.
Id. at col. 8 ll. 40–42.
10. A system for use in controlling a vehicle at a
vehicle speed, said system including:
an adaptive cruise control system;
a controller in communication with said adaptive
cruise control system and capable of determining
when the vehicle is in a turn, said controller oper-
ative to reduce the vehicle speed according to a ve-
hicle position in the turn;
at least one lateral acceleration sensor for generat-
ing a signal corresponding to a vehicle lateral ac-
celeration, said lateral acceleration sensor in
electrical communication with said controller and
operative to detect a change in the vehicle lateral
acceleration; and
at least one object detection sensor for detecting an
object in a vehicle path of the vehicle during the
turn, said object detection sensor in electrical com-
munication with said controller, wherein said con-
troller includes control logic operative to determine
whether the object is in the vehicle path during the
turn and ignoring the object for braking purposes
when the object is not determined to be in the vehi-
cle path.
Id. at col. 8 l. 63–col.9 l. 16 (disputed terms emphasized).
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CARRUM TECHNOLOGIES , LLC v. FORD MOTOR COMPANY 6
In Ford, the district court granted summary judgment
of noninfringement based on its constructions of the dis-
puted terms. First, applying our reasoning in Salazar and
Finjan, the district court construed “a controller” and “said
controller” to “require[] that at least one controller be capa-
ble of performing each of the ‘said controller’ limitations,”
rejecting an argument that the controller functionality
could be distributed among one or more controllers. Ford
Decision, 2023 WL 7407778 at *5 (citing Salazar v. AT&T
Mobility LLC, 64 F.4th 1311, 1317 (Fed. Cir. 2023); Finjan
LLC v. SonicWall, Inc., 84 F.4th 963, 974 (Fed. Cir. 2023)).
In view of its construction, the district court determined
that there was “no genuine dispute of material fact on the
‘controller’ issue” because Ford’s accused vehicles do not
utilize a single controller that performs all of the claimed
functions. Id. Accordingly, the district court granted sum-
mary judgment of noninfringement of claims 10, 11, and 12
of the ’416 patent. Id.
Second, relying primarily on intrinsic evidence, the dis-
trict court construed “change in . . . vehicle lateral acceler-
ation” as “a vehicle lateral acceleration that is different
[from] a previous vehicle lateral acceleration.” Id. at *10
(cleaned up). Based on that construction, the district court
determined that there was “no genuine dispute of material
fact on the ‘change’ issue” because Ford’s accused vehicles
act on a “magnitude” system and thus “do not use a formula
that compares one lateral acceleration value with another.”
Id. Accordingly, the district court granted summary judg-
ment of noninfringement of claim 5 of the ’475 patent and
claim 6 of the ’416 patent.3 Id.
3 The district court did not grant summary judgment
of noninfringement of claims 10–12 of the ’416 patent based
on its construction of the “change” limitation. See Ford De-
cision, 2023 WL 7407778 at *10. Rather, it did so based
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CARRUM TECHNOLOGIES , LLC v. FORD MOTOR COMPANY 7
After filing suit against Ford, Carrum brought suit
against BMW alleging infringement of the same patents.
In BMW, the parties agreed that the term “said controller”
meant “the same controller as previously referred to in the
claim,” and the district court adopted that construction.
BMW Decision, 2023 WL 9744835 at *1. However, the par-
ties disputed four other terms, including the term “change
in . . . vehicle lateral acceleration” of claims 1 and 6 of the
’416 patent. Id. The district court construed that term,
consistent with its construction in Ford, to mean “a vehicle
lateral acceleration that is different [from] a previous vehi-
cle lateral acceleration.” Id. (cleaned up). Following the
district court’s claim construction, the parties stipulated to
noninfringement of the only remaining asserted claim
against BMW, i.e., claim 6 of the ’416 patent.4 J.A. 104–
only on the “controller” limitation, see id. at *5, likely be-
cause Ford’s summary judgment arguments for claims 10–
12 were limited to that “controller” issue, see J.A. 1179–82.
Post-appellate argument, the parties now dispute via letter
whether we can nonetheless affirm the district court’s sum-
mary judgment of noninfringement of claims 10–12 based
on the “change” limitation. See ECF No. 73; ECF No. 74.
We may not. As noted, the district court did not reach its
judgment on that basis, and, in any event, the structure of
the “change” term in method claim 6 is different from that
of the “change” term in system claims 10–12 of the ’416 pa-
tent. Compare ’416 patent col. 8 ll. 10–11 (“determining
when the vehicle is in a turn based on a detected change in
the vehicle lateral acceleration” (emphasis added)), with id.
at col. 9 ll. 3–7 (“one lateral acceleration sensor . . . opera-
tive to detect a change in the vehicle lateral acceleration”
(emphasis added)).
4 Carrum reserved the right to challenge the con-
struction of “change in . . . lateral acceleration” on appeal.
BMW Decision, 2023 WL 9744835 at *1.
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CARRUM TECHNOLOGIES , LLC v. FORD MOTOR COMPANY 8
110. The district court then granted summary judgment of
noninfringement of claim 6 in favor of BMW. J.A. 111.
Carrum timely appealed from the Ford and BMW deci-
sions. We have jurisdiction under 28 U.S.C. § 1295(a)(1).
D ISCUSSION
Carrum challenges the district court’s claim construc-
tions. First, Carrum argues that the district court erred by
construing “a controller” to require that there be at least
one controller that performs each recited function. Carrum
Op. Br. 29–39. Second, Carrum contends that the district
court erred by construing the “change” term to exclude a
change identified by a comparison to a predetermined
threshold. Id. at 20–29. We discuss each issue in turn.
I
“We review claim construction based on intrinsic evi-
dence de novo and review any findings of fact regarding ex-
trinsic evidence for clear error.” Regeneron Pharms., Inc.
v. Mylan Pharms. Inc., 130 F.4th 1372, 1378 (Fed. Cir.
2025) (citation omitted). “Claim terms are generally given
their plain and ordinary meaning, which is the meaning
that one of ordinary skill in the art would ascribe to a term
when read in the context of the claims, specification, and
prosecution history.” Id. at 1378–79 (citing Phillips v.
AWH Corp., 415 F.3d 1303, 1313–17 (Fed. Cir. 2005)).
A
We begin with the construction of “a” and “said” “con-
troller,” which only pertains to Ford on appeal. “We have
explained that the indefinite article ‘a’ means ‘one or more’
in open-ended claims containing the transitional phrase
‘comprising.’” See Salazar, 64 F.4th at 1315 (cleaned up).
We have also explained that “[t]he subsequent use of defi-
nite articles ‘the’ or ‘said’ in a claim to refer back to the
same claim term does not change the general plural rule
[of ‘a’], but simply reinvokes that non-singular meaning.”
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CARRUM TECHNOLOGIES , LLC v. FORD MOTOR COMPANY 9
Id. (quoting Baldwin Graphic Sys., Inc. v. Siebert, Inc.,
512 F.3d 1338, 1342 (Fed. Cir. 2008) (cleaned up)).
While the general rule that “a” means “one or more”
leaves open the numerical scope of the limitation, it does
not relax the substantive requirement that at least one in-
stantiation of “a” must embody all of its recited functions
when the remaining context of the claim so requires. See
In re Varma, 816 F.3d 1352, 1362 (Fed. Cir. 2016) (“[W]hile
‘a’ sometimes is non-restrictive as to number, permitting
the presence of more than one of the objects following that
indefinite article, context matters even as to whether the
word has that meaning.” (citation omitted)); see, e.g., Sala-
zar, 64 F.4th at 1317 (holding that “while the claim term ‘a
microprocessor’ does not require there be only one micro-
processor, the subsequent limitations referring back to
‘said microprocessor’ require that at least one microproces-
sor be capable of performing each of the claimed functions”
due, at least in part, to the structural relationship between
the subject “processer” and other structural limitations of
the claim).
Thus, “the question is not whether there can be more
than one [controller] . . . : there can. Rather, the question
is whether ‘a’ can serve to negate what is required by the
language following ‘a.’” In re Varma, 816 F.3d at 1362–63.
Here, the claimed “a controller” is followed by language
that operatively ties “said controller” to the claimed “adap-
tive cruise control system” to perform its multiple recited
functions. See ’416 patent col. 8 l. 66–col. 9 l. 16. Specifi-
cally, claim 10 requires a “controller” that is “in communi-
cation with” the “adaptive control system” and is (1)
“capable of determining when the vehicle is in a turn” and
“operative to reduce the vehicle speed,” id. at col. col. 8 l.
66–col. 9 l. 2, and (2) “operative to determine whether the
object is in the vehicle path during the turn and ignoring
the object for braking purposes when the object is not de-
termined to be in the vehicle path,” id. at col. 9 ll. 12–15.
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CARRUM TECHNOLOGIES , LLC v. FORD MOTOR COMPANY 10
The “a” before “controller” therefore cannot negate
claim 10’s other requirements. Rather, because the claim
language ties the “controller” to the claimed ACC system,
at least one of the one or more controllers must perform
each of its recited functions. See, e.g., Convolve, Inc. v.
Compaq Comput. Corp., 812 F.3d 1313, 1321 (Fed. Cir.
2016) (holding that at least one claimed “processor” must
perform all recited steps, when the claim language re-
quired “a processor associated with the user interface to is-
sue the shaped commands of the claims,” and the user
interface was therefore “operatively working with” the
same processor to perform all steps (internal quotation
omitted and emphasis added)). In short, the required func-
tions of the “controller” follow its tie to the ACC system and
become attributes of that controller-ACC combination, not
of the system in the abstract.
The specification is consistent with the plain meaning
of the claims. In relevant part, it provides:
Controller 222 may be a portion of a main control
unit such as vehicle’s 200 main controller, or con-
troller 222 may be a stand-alone controller. Con-
troller 222 contains logic for enabling vehicle 200
to reduce its speed in a turn as well as to ignore
objects positioned outside of a specific safety zone
area.
’416 patent col. 5 ll. 2–7 (emphasis added). In other words,
the specification discloses that controller 222 is capable of
performing both functions recited by claim 10—reducing
vehicle speed in a turn and avoiding objects in the road.
See id. at col. 9 ll. 1–2, 11–15.5
Carrum’s arguments to the contrary are misplaced.
Carrum misapplies the effect of “said” on the construction
5 Figures 3 and 4 illustrate how that process works.
See id. at col. 5. ll. 9–28.
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CARRUM TECHNOLOGIES , LLC v. FORD MOTOR COMPANY 11
of “a controller” and overreads the specification to contend
that “a” requires that the “controller” functionality is dis-
tributed across one or more controllers. See Carrum Op.
Br. 31–36. Specifically, Carrum argues that the use of
“said” merely reinforces the non-singular meaning of “a
controller” irrespective of other claim language. Id. at 31.
But we have rejected a similar argument, explaining that
while the use of “‘said’ . . . reinvokes th[e] non-singular
meaning[,]” it “does not negate what is required by the lan-
guage [that] follows ‘said.’” Salazar, 64 F.4th at 1318 (ci-
tation omitted) (cleaned up). Likewise, here, the use of
“said” does not negate the language in claim 10 that follows
the use of “said.” See ’416 patent col. 8 l. 66–col. 9 l. 16.
That language, as discussed above, operatively ties the
“controller” to the ACC system such that the same control-
ler performs its recited functions. See id.
Carrum appears to ignore that other claim language
accompanying “said,” and instead relies on a flawed read-
ing of the specification. That the specification indicates
that “controller 222” may be part of “main control unit”
does not suggest, let alone require, that claim 10’s “control-
ler” functionality is “distributed” across multiple control-
lers as Carrum contends. See Carrum Op. Br. 32–34; ’416
patent col. 5 ll. 2–8. Rather, the specification merely dis-
closes a “main control unit” that contains controllers, one
of which may be controller 222. ’416 patent col. 5 ll. 2–4.
Even if controller 222 is part of the “main control unit,”
that does not mean that controller 222’s functionality is
distributed among other controllers that are part of the
“main control unit” or even that controller 222’s function-
ality is shared among multiple controller 222s.
At most, the specification discloses that multiple con-
trollers may assist in performing the methods of ’416 pa-
tent. That reading does not conflict with claim 10’s plain
requirement that at least one of “said controller[(s)]” per-
form all of its recited functions. Nor can the specification
be used to read that plain limitation out of claim 10. See
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CARRUM TECHNOLOGIES , LLC v. FORD MOTOR COMPANY 12
Texas Instruments v. U.S. Int’l Trade Comm’n, 988 F.2d
1165, 1171 (Fed. Cir. 1993) (rejecting a claim construction
argument that “would read an express limitation out of the
claims . . . because courts can neither broaden nor narrow
claims to give the patentee something different than what
he has set forth” (cleaned up)).
Finally, Carrum heavily relies on our decision in 01
Communique Lab’y, Inc. v. LogMeIn, Inc., 687 F.3d 1292
(Fed. Cir. 2012) to argue “that ‘a controller’ must mean ‘one
or more controllers[]’ because controllers may be combined
or subdivided.” Carrum Op. Br. 35–36. But that case is
inapposite. Indeed, in 01 Communique “we concluded that
‘a location facility’ could ‘be distributed among multiple
locator server computers.’” Finjan, 84 F.4th at 973 (quot-
ing 01 Communique, 687 F.3d at 1296). But “01 Commu-
nique” does not answer the relevant question here:
“whether the same [controller] must perform each of sev-
eral subsequent claim limitations referring to that [control-
ler].” Finjan, 84 F.4th at 975 (emphasis added).
In sum, we agree that the plain language of the claims
requires that at least one of the one or more controllers per-
forms all of the controller’s recited functions. Accordingly,
we also affirm the district court’s judgment of noninfringe-
ment of the ’416 patent in Ford.
B
We turn next to the construction of the term “change
in . . . vehicle lateral acceleration.” Carrum “does not dis-
pute that a ‘change in a vehicle lateral acceleration’ means
‘a vehicle lateral acceleration that is different [from] a pre-
vious vehicle lateral acceleration’” as construed by the dis-
trict court. Carrum Op. Br. 22 (quoting Ford Decision,
2023 WL 7407778 at *10) (cleaned up). Rather, Carrum
disagrees with the scope that the district court afforded to
that construction. It contends that the district court erred
by excluding from that construction a particular type of
change: “a change identified by comparison to a
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CARRUM TECHNOLOGIES , LLC v. FORD MOTOR COMPANY 13
predetermined threshold.” Id. at 20 (cleaned up). Specifi-
cally, it argues that “[d]etermining that a value was previ-
ously below a predetermined threshold, and is now above
that threshold, is simply one way to determine that the
value ‘is different [from] a previous’ value.” Id. at 22–23
(cleaned up). We disagree.
Step two of exemplary method claim 1 of the ’475 pa-
tent recites: “detecting a change in a vehicle lateral accel-
eration based on a change in the measured lateral
acceleration.” col. 8 ll. 13–14. “Change” as a noun means
“the act, process, or result of changing,” and the verb “to
change” means “to become different.” See change, Mer-
riam-Webster Dictionary, https://www.merriam-web-
ster.com/dictionary/change (last visited Sept. 30, 2025).
Thus, as the district court put it, “in the context of the pa-
tents, ‘change’ indicates that the system detects that a par-
ticular lateral acceleration value has become different
[from] a previous lateral acceleration value.” Ford Deci-
sion, 2023 WL 7407778 at *8 (emphasis added) (cleaned
up). The plain meaning of that term, therefore, presumes
the obvious: one lateral acceleration cannot “become differ-
ent” in a vacuum; it must be different from another.
The specification reinforces that plain meaning and
further demonstrates that comparing a particular lateral
acceleration value to a magnitude (i.e., a predetermined
threshold) is not “one way to determine that the value ‘is
different [from] a previous’ value,” as Carrum contends.
Carrum Op. Br. 22–23 (cleaned up). “The only meaning
that matters in claim construction is the meaning in the
context of the patent.” Trs. of Columbia Univ. in City of N.
Y. v. Symantec Corp., 811 F.3d 1359, 1363 (Fed. Cir. 2016)
(citations omitted). Here, the specification consistently de-
scribes the step of “detecting a change” as comparing two
measured acceleration values. The specification does so by
repeatedly describing claim 1’s requirement of “determin-
ing when the vehicle is in a turn based on the detected
change in the vehicle lateral acceleration.” See ’475 patent
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CARRUM TECHNOLOGIES , LLC v. FORD MOTOR COMPANY 14
col. 5 ll. 57–67 (explaining claim 1’s requirements in de-
tail); id. at col. 8 ll. 15–16 (claim 1 in part). Specifically,
the specification describes how to “deduce when a vehicle is
in a turn” by deriving “a vehicle’s lateral acceleration in a
turn” as follows:
[T]he following characteristics of a vehicle’s lateral
acceleration in a turn may be derived: 1) in the en-
try of a turn, the lateral acceleration of a vehicle is
likely to rapidly increase from zero (0) Gs over time;
2) in the middle of a turn, the lateral acceleration
of a vehicle is likely to show a constant increase be-
fore reaching a maximum value; and 3) in the exit
of a turn, the lateral acceleration of a vehicle is
likely to remain steady for a short period of time
before decreasing. These characteristics may be
used to program controller 222 both to deduce
when a vehicle is in a turning situation and to de-
termine at what position the vehicle is in within
the turn.
’475 patent col. 5 ll. 57–67. The specification therefore “in-
dicates that the ‘change’ used to determine whether a vehi-
cle is in a turn involves comparing a particular lateral
acceleration value to a previous lateral acceleration value,”
as the district court identified. Ford Decision, 2023 WL
7407778 at *9.
Moreover, the only time that the specification mentions
comparing a lateral acceleration to a magnitude, or “a pre-
determined maximum limit,” is after the steps described
above regarding how to deduce when a vehicle is in a turn
and in what position it is in. ’475 patent col. 6 ll. 28–29.
To be clear, the specification first describes that “controller
222 determines vehicle’s 302 position within the turn by
using programmed instructions that recognize patterns ex-
hibited in lateral acceleration data when a vehicle is in the
entry of a turn, in the middle of a turn, or exiting a turn.”
’475 patent col. 6 ll. 20–24 (emphasis added). The next
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CARRUM TECHNOLOGIES , LLC v. FORD MOTOR COMPANY 15
sentence of the specification then describes that “[a]fter
controller 222 determines at step 410 where in turn 306
vehicle 302 is positioned, controller 222 then instructs
braking system 212 at step 412 to preemptively reduce ve-
hicle’s 302 speed so that vehicle’s 302 lateral acceleration
speed is reduced [t]o a predetermined maximum limit ac-
cording to vehicle’s 302 position in the turn.” Id. at col. 6
ll. 24–29 (emphases added).
The specification’s description—adjusting a lateral ac-
celeration to a magnitude only after the other steps of de-
tecting when, and where, a vehicle is in a turn based on
patterns of lateral acceleration data—is consistent with the
language and structure of the claims. Claim 1 requires (1)
detecting changes in measured lateral accelerations, (2) de-
termining whether the vehicle is in a turn based on any
detected change in lateral acceleration, and (3) reducing
the speed if a vehicle is in a turn. See id. at col. 8 ll. 11–19.
Only once those steps are performed, does dependent claim
5 further require “reducing the speed if the vehicle lateral
acceleration exceeds a predetermined limit.” Id. at col. 8 ll.
33–34. Thus, claim 5’s magnitude comparison is not itself
a type of “change” in lateral acceleration, but an additional
step that governs how the speed-reduction function is car-
ried out.
Because the specification, consistent with the claims,
uniformly describes “detecting a change in . . . vehicle lat-
eral acceleration” as a direct comparison of two vehicle lat-
eral accelerations, see ’475 patent col. 5 ll. 57–67, such
description informs the meaning of the claims and excludes
a magnitude-based comparison even without any clear dis-
avowal. See, e.g., Regeneron, 130 F.4th at 1383 (affirming
a narrower construction of a term, despite no clear disa-
vowal, because the claim “arose from a specification that
clearly and repeatedly describes [that term]” in a particu-
lar manner “and does not explain or suggest” the broader
construction argued for (cleaned up)); see also Sound View
Innovations, LLC v. Hulu, LLC, 33 F.4th 1326, 1333 (Fed.
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CARRUM TECHNOLOGIES , LLC v. FORD MOTOR COMPANY 16
Cir. 2022) (affirming a construction, at least in part, be-
cause “the specification nowhere says that the invention in-
cludes use of separate buffers . . ., and it nowhere
illustrates or describes such an embodiment”). As such, the
claims and specification distinguish a magnitude-based
system that merely detects whether a lateral acceleration
is above or below a threshold from the claimed system that
detects changes from one lateral acceleration to the next.
It is against this backdrop that we consider the prose-
cution history. During prosecution, the patentee stated
that “a change in a variable is not at all the same thing as
the magnitude of a variable.” J.A. 4038. While this does
not resolve the claim construction issue before the court—
because the patentee was only arguing that a “magnitude”
itself is not a type of “change,” not that the scope of the
term “change” could not include a comparison of some
value to a predetermined magnitude—it nevertheless is
consistent with the district court’s construction because, as
the district court explained, it “supports distinguishing
‘change’ from ‘magnitude.’” Ford Decision, 2023 WL
7407778 at *9.
We therefore agree with the district that a “change
in . . . vehicle lateral acceleration” means “a vehicle lateral
acceleration that is different [from] a previous vehicle lat-
eral acceleration,” which excludes a magnitude-based sys-
tem. Id. at *10 (cleaned up). Accordingly, we also affirm
the district court’s judgments of noninfringement of the
’475 and ’416 patents in Ford and of the ’416 patent in
BMW.
CONCLUSION
We have considered Carrum’s remaining arguments
and find them unpersuasive. For the foregoing reasons, we
affirm.
AFFIRMED
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