Ossur HF et al v. iWalk Inc

Filing 168

Judge F. Dennis Saylor, IV: MEMORANDUM AND ORDER entered on CLAIM CONSTRUCTION. (Cicolini, Pietro)

UNITED STATES DISTRICT COURT
DISTRICT OF MASSACHUSETTS
_______________________________________
)
ÖSSUR HF and ÖSSUR AMERICAS, INC., )
)
Plaintiffs,
)
)
v.
)
)
iWALK, INC.,
)
)
Defendant.
)
_______________________________________)

Civil Action No.
12-11061-FDS

MEMORANDUM AND ORDER ON
CLAIM CONSTRUCTION
SAYLOR, J.
This is a patent dispute involving sophisticated prosthetic limbs—specifically, devices
that function as feet and ankles for patients whose legs have been amputated below the knee.
Plaintiffs Össur HF and Össur Americas, Inc., (collectively “Össur”) design and manufacture
prostheses, including a microprocessor-controlled prosthetic foot/ankle system. Össur seeks a
judgment that a prosthetic foot/ankle system manufactured and sold by defendant iWalk, Inc.,
infringes upon its patents. iWalk has asserted, among other things, defenses of non-infringement
and invalidity of the patents.
The parties’ allegations hinge in part on the construction of the claims in Össur’s U.S.
Patent No. 7,431,737 (the “’737 patent”) and U.S. Patent No. 7,896,927 (the “’927 patent”). The
Court conducted a Markman hearing on the construction of the relevant claims on February 25,
2013.
Össur and iWalk dispute twelve terms: (1) “gait pattern(s) or event(s),” (2) “ankle-angle

adjustments,” (3) “processing module,” (4) “substantially mimicking the movement of a healthy
ankle,” (5) “subsequent gait cycles,” (6) “corresponding to [a/the] determined gait pattern or
event,” (7) “position,” (8) “movement,” (9) “state transition is detected from the determined gait
pattern or event to a different gait pattern or event,” (10) “relaxed position” (and related
phrases), (11) “configurable element,” and (12) “automatically adjusting.” iWalk also contends
that three of the disputed terms are indefinite and therefore render the relevant claims invalid.
I.

Background
Össur is an Icelandic company that designs and sells products and technologies in the

fields of prosthetics, orthotics, bracing and supports, and compression therapy. The patents at
issue here concern a microprocessor-controlled prosthetic foot/ankle system called the “Proprio
Foot.”
iWalk is a Massachusetts-based company that designs and sells prostheses. The company
was founded in 2006 by an MIT professor, Dr. Hugh Herr, who became a bilateral amputee after
a 1982 climbing accident. After designing his own prostheses for personal use, Dr. Herr founded
iWalk to design and sell prostheses on the commercial market. Since 2011, the company has
sold a powered foot/ankle prosthesis, called the “PowerFoot BiOM,” which is the subject of
Össur’s infringement contentions.
Össur filed the application that ultimately produced the ’737 patent on February 11,
2005. The ’737 patent was issued on October 7, 2008. Össur filed the application for the ’927
patent on March 1, 2006. The ’927 patent was issued on March 1, 2011. The ’737 patent is
directed to systems and methods for controlling a prosthetic foot/ankle system. The ’927 patent
is a continuation of the ’737 patent, claiming refinements to the invention.

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On November 15, 2011, Össur filed this action, alleging that iWalk has infringed both the
’927 and ’737 patents. Specifically, Össur contends that iWalk has infringed on claims 1, 3, 6, 7,
21, 22, 33, and 34 of the ’737 patent and claims 1, 2, 5, 7, and 11 of the ’927 patent.
Claims 1, 3, 6, 7, 21, 22, 33, and 34 of the ’737 patent read as follows:
1.

A method for controlling an ankle device associated with the movement of a limb,
the method comprising: monitoring, with at least one sensor, at least one of
position and movement of an ankle device associated with a limb throughout at
least one gait cycle, wherein the device comprises a foot unit, a lower limb
member, and at least one actuator; generating data indicative of the at least [sic]
one of position and movement throughout the at least [sic] one gait cycle;
processing the data with a processing module to determine if the data corresponds
to one of a plurality of defined gait patterns or events, wherein information
defining said plurality of gait patterns or events is stored in a memory of the
device; determining ankle-angle adjustments corresponding to a determined gait
pattern or event; and adjusting the device based on the determined ankle-angle
adjustments corresponding to the determined gait pattern or event, wherein the
adjusting comprises actuating the at least [sic] one actuator to move the lower
limb member relative to the foot unit in a manner substantially mimicking
movement of a healthy ankle, said ankle-angle adjustments being applied over a
swing phase of subsequent gait cycles until a state transition is detected from the
determined gait pattern or event to a different gait pattern or event.

3.

The method of claim 1, wherein the device comprises a prosthetic device.

6.

The method of claim 1, wherein the at least [sic] one sensor is located on the
device.

7.

The method of claim 1, wherein the actuating comprises at least one of the
following: extending and contracting the at least [sic] one actuator.

21.

The method of claim 1, wherein the device associated with a limb is a device
attachable to a limb.

22.

The method of claim 1, wherein the plurality of defined gait patterns or events
comprises at least one of the following: stance, level ground walking, ascending
stairs, descending stairs, incline, decline, sitting down, sitting, standing up, adjust
heel height, off, heel height calibration, sensor calibration, neutral, relax, and
pants.

33.

The method of claim 1, wherein a gait cycle comprises one full stride of a user.
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34.

The method of claim 1, wherein the determined ankle-angle adjustments comprise
at least one of the following: toe clearance; user set point; set heel height; relax
ankle; a desired degree of dorsiflexion; a desired degree of plantarfiexion; ten
degrees of dorsiflexion; five degrees of dorsiflexion; seven and a half degrees of
dorsiflexion; 20 degrees of plantarfiexion; an ankle angle associated with an
incline angle threshold level; an ankle angle associated with a decline angle
threshold level; an ankle angle associated with an incline angle of five degrees; an
ankle angle with an incline angle of two and a half degrees; an ankle angle
associated with a decline angle of five degrees; and an ankle angle associated
with a decline angle of two and a half degrees.

Claims 1, 2, 5, 7, and 11 of the ’927 patent read as follows:
1.

A method for adjusting a prosthetic ankle device, the method comprising:
monitoring with at least one sensor the movement of a user of a prosthetic ankle
device; generating data indicative of the movement; processing the data with a
processing module to determine whether the user is in a relaxed position, wherein
the relaxed position is a sitting position; and adjusting the prosthetic ankle device
based on whether the user is in the relaxed position, wherein adjusting the
prosthetic ankle device comprises automatically adjusting a configurable element
of the prosthetic ankle device.

2.

The method of claim 1, wherein the at least [sic] one sensor is located on the
prosthetic ankle device.

5.

The method of claim 1, wherein monitoring with the at least [sic] one sensor the
movement of the user of the prosthetic ankle device comprises monitoring an
acceleration of the prosthetic ankle device.

7.

The method of claim 1, wherein monitoring with the at least [sic] one sensor the
movement of the user of the prosthetic ankle device comprises monitoring a
length of time that the user of the prosthetic ankle device exhibits a movement
characteristic indicative of the relaxed position of the user.

11.

The method of claim 1, wherein the configurable element is the amount of
operating power.

These claims describe methods that allow a prosthetic foot/ankle system to mimic the
movement and function of a healthy human ankle. A human foot and ankle go through a series
of motions and provide support in different ways during the course of daily activities.
Particularly important to the patents at issue are the movements during normal walking, or
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“gait,” and the functions of those movements. When describing such movements, those skilled
in the art, often refer to a period known as a “gait cycle.” A “gait cycle” is a full stride spanning
from one heel-strike to the next heel-strike of the same foot. Within a gait cycle, there are two
general phases: the stance phase (the period of time when the foot is touching the ground) and
the swing phase (the period of time when the foot is off the ground). Within these phases the
foot engages in, and is in positions of, both “plantarflexion” and “dorsiflexion.” “Dorsiflexion”
describes the action of decreasing the angle between the ankle and the foot, and also refers to the
position of the foot where the angle between the ankle and the foot is less than 90 degrees.
“Plantarflexion” describes the action of increasing the angle between the ankle and the foot, and
also refers to the position of the foot where the angle between the ankle and the foot is greater
than 90 degrees.
The prosthesis used to practice the claimed methods must have a foot unit and a “lower
limb member” (in other words, an ankle unit) that pivot relative to one another. The prostheses
must also be able to control the angle between the foot unit and the lower limb member (the
“ankle-angle”). Claim 1 of the ’737 patent describes a method for achieving appropriate
ankle-angle adjustments during the swing phase so that the device “substantially mimic[s]
movement of a healthy ankle.” The claimed method teaches monitoring data, throughout a
wearer’s gait cycle, about the position or movement of the device, and then comparing that data
to pre-stored data corresponding to states of activity (referred to as “gait patterns or
events”)—for example, walking up an incline or descending stairs—to determine the wearer’s
current gait pattern. The claimed method involves adjusting the ankle-angle during subsequent
swing phases based on this data. Claim 1 of the ’927 patent similarly describes a method for

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achieving appropriate ankle-angle adjustments when the wearer is in a “relaxed position.”
Össur’s Proprio Foot is the apparatus designed to practice these methods, and is
consequently the commercial embodiment of the claims at issue. The Proprio Foot is
a microprocessor-controlled prosthetic foot/ankle system that uses data it collects to perform
ankle-angle adjustments as described in the patents.
Össur contends that iWalk’s BiOM, which is a powered foot-and-ankle prosthesis, also
practices the methods of the patents at issue. The BiOM mimics the movement of a healthy
ankle during stance phase by using a control system that emulates spinal-cord reflexes but does
not utilize pre-programmed ankle positions. The BiOM also provides powered plantarflexion
during the stance phase—in other words, the forefoot pushes off the ground before each walking
step. During the swing phase, the BiOM returns the foot to a neutral position where it has a hard
mechanical stop.
In response to Össur’s infringement allegations, iWalk first contends that the asserted
claims are invalid because three of the terms used in those claims are indefinite. Specifically,
iWalk contends that the terms “gait pattern(s) or event(s),” “substantially mimicking the
movement of a healthy ankle,” and “configurable element” are indefinite. The parties also
generally contest the interpretation of twelve separate terms used to describe the methods in the
claims recited above. The terms in dispute are: (1) “gait pattern(s) or event(s),” (2) “ankle-angle
adjustments,” (3) “processing module,” (4) “substantially mimicking the movement of a healthy
ankle,” (5) “subsequent gait cycles,” (6) “corresponding to [a/the] determined gait pattern or
event,” (7) “position,” (8) “movement,” (9) “state transition is detected from the determined gait
pattern or event to a different gait pattern or event,” (10) “relaxed position” (and related

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phrases), (11) “configurable element,” and (12) “automatically adjusting.”
II.

Legal Framework
The construction of claim terms is a question of law. Markman v. Westview Instruments,

517 U.S. 370, 372 (1996) (“[T]he construction of a patent, including terms of art within its claim,
is exclusively within the province of the court.”).
In Phillips v. AWH Corp., 415 F.3d 1303 (Fed. Cir. 2005) (en banc), the Federal Circuit
clarified the proper approach to claim construction and set forth principles for determining the
hierarchy and weight of the definitional sources that give the patent its meaning. The guiding
principle of construction is “the meaning that the term would have to a person of ordinary skill in
the art in question at the time of . . . the effective filing date of the patent application.” Id. at
1313. Courts thus seek clarification of meaning in “the words of the claims themselves, the
remainder of the specification, the prosecution history, and extrinsic evidence concerning
relevant scientific principles, the meaning of technical terms, and the state of the art.” Id. at
1314 (quoting Innova/Pure Water, Inc. v. Safari Water Filtration Sys., 381 F.3d 1111, 1116
(Fed. Cir. 2004)).

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A.

The Words of the Claims Themselves

The claim construction analysis normally begins with the claims themselves.1 The claims
of a patent “define the invention to which the patentee is entitled the right to exclude.” Id. at
1312 (citing Innova, 381 F.3d at 1115).
As a preliminary matter, it is well-established that a court may construe a claim term to
have its plain meaning when such a construction resolves a dispute between the parties. See O2
Micro Int’l Ltd. v. Beyond Innovation Tech. Co., 521 F.3d 1351, 1361 (Fed. Cir. 2008) (“A
determination that a claim term ‘needs no construction’ or has the ‘plain and ordinary meaning’
may be inadequate when a term has more than one ‘ordinary’ meaning or when reliance on a
term’s ‘ordinary’ meaning does not resolve the parties’ dispute. . . .[When] the ‘ordinary’
meaning of a term does not resolve the parties’ dispute . . . claim construction requires the court
to determine what claim scope is appropriate in the context of the patents-in-suit.”); Finjan Inc.
v. Secure Computing Corp., 626 F.3d 1197, 1206-07 (Fed. Cir. 2010); see also U.S. Surgical
Corp. v. Ethicon, Inc., 103 F.3d 1554, 1568 (Fed. Cir. 1997) (“Claim construction is a matter of
resolution of disputed meanings and technical scope, to clarify and when necessary to explain
what the patentee covered by the claims, . . . [but] is not an obligatory exercise in redundancy.”).

1

In Phillips, the Federal Circuit discredited the practice of starting the claim construction analysis with
broad definitions found in dictionaries and other extrinsic sources:
[I]f the district court starts with the broad dictionary definition . . . and fails to fully appreciate how
the specification implicitly limits that definition, the error will systematically cause the
construction of the claim to be unduly expansive. The risk of systematic overbreadth is greatly
reduced if the court instead focuses at the outset on how the patentee used the claim term in the
claims, specification, and prosecution history, rather than starting with a broad definition and
whittling it down.
Id. at 1321. Of course, if no special meaning is apparent after reviewing the intrinsic evidence, claim construction
might then “involve[] little more than the application of the widely accepted meaning of commonly understood
words.” Id. at 1314.

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In some instances, it is the arrangement of the disputed term in the claims that is
dispositive. “This court’s cases provide numerous . . . examples in which the use of a term
within the claim provides a firm basis for construing the term.” Phillips, 415 F.3d at 1314. For
example, because claim terms are normally used consistently throughout the patent, the meaning
of a term in one claim is likely the meaning of that same term in another. Id. In addition, “the
presence of a dependent claim that adds a particular limitation gives rise to a presumption that
the limitation in question is not present in the independent claim.” Id. at 1315.
B.

The Specification

“The claims, of course, do not stand alone.” Id. at 1315. Rather, “they are part of a fully
integrated written instrument, consisting principally of a specification that concludes with the
claims.” Id. (internal citations and quotations omitted). For that reason, the specification must
always be consulted to determine a claim’s intended meaning. “[T]he specification is always
highly relevant to the claim construction analysis. Usually, it is dispositive; it is the single best
guide to the meaning of a disputed term.” Id. (citing Vitronics Corp. v. Conceptronic, Inc., 90
F.3d 1576, 1582 (Fed. Cir. 1996)).
“In general, the scope and outer boundary of claims is set by the patentee’s description of
his invention.” On Demand Mach. Corp. v. Ingram Indus., 442 F.3d 1331, 1338 (Fed. Cir.
2006); see also Phillips, 415 F.3d at 1315-1317 (“[T]he interpretation to be given a term can
only be determined and confirmed with a full understanding of what the inventors actually
invented and intended to envelop with the claim”). “[T]he specification may reveal a special
definition given to a claim term by the patentee that differs from the meaning it would otherwise
possess.” Phillips, 415 F.3d at 1316. It may also reveal “an intentional disclaimer, or disavowal,

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of claim scope by the inventor.” Id. Therefore, the claims are to be construed in a way that
makes them consistent with, and no broader than, the invention disclosed in the specification.
On Demand, 442 F.3d at 1340 (“[C]laims cannot be of broader scope than the invention that is
set forth in the specification.”); Phillips, 415 F.3d at 1316 (“[C]laims must be construed so as to
be consistent with the specification, of which they are a part.”).
Nevertheless, courts must be careful to “us[e] the specification [only] to interpret the
meaning of a claim” and not to “import[] limitations from the specification into the claim.”
Phillips, 415 F.3d at 1323; see also Gillette Co. v. Energizer Holdings, Inc., 405 F.3d 1367, 1375
(Fed. Cir. 2005) (internal quotations omitted). A patent’s “claims, not specification
embodiments, define the scope of patent protection.” Kara Tech. Inc. v. Stamps.com Inc., 582
F.3d 1341, 1348 (Fed. Cir. 2009); see also Martek Biosciences Corp. v. Nutrinova, Inc., 579
F.3d 1363, 1381 (Fed. Cir. 2009) (“[E]mbodiments appearing in the written description will not
be used to limit claim language that has broader effect.”). “In particular, we have expressly
rejected the contention that if a patent describes only a single embodiment, the claims of the
patent must be construed as being limited to that embodiment.” Phillips, 415 F.3d at 1323. This
is “because persons of ordinary skill in the art rarely would confine their definitions of terms to
the exact representations depicted in the embodiments.” Id.
Although this distinction “can be a difficult one to apply in practice[,] . . . the line
between construing terms and importing limitations can be discerned with reasonable certainty
and predictability if the court's focus remains on understanding how a person of ordinary skill in
the art would understand the claim terms.” Id. Ultimately, “[t]he construction that stays true to
the claim language and most naturally aligns with the patent's description of the invention will

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be, in the end, the correct construction.” Id. at 1316 (citing Renishaw PLC v. Marposs Societa’
per Azioni, 158 F.3d 1243, 1250 (Fed. Cir. 1998).
C.

The Prosecution History

After the specification and the claims themselves, the prosecution history is the next best
indicator of term meaning. The prosecution history consists of the complete record of the
proceedings before the PTO and includes the prior art cited during the examination of the patent.
Id. at 1317. “Like the specification, the prosecution history provides evidence of how the PTO
and the inventor understood the patent.” Id. “[T]he prosecution history can often inform the
meaning of the claim language by demonstrating how the inventor understood the invention and
whether the inventor limited the invention in the course of prosecution, making the claim scope
narrower than it would otherwise be.” Id. (citing Vitronics, 90 F.3d at 1582-83).
However, “because the prosecution history represents an ongoing negotiation between
the PTO and the applicant, rather than the final product of that negotiation, it often lacks the
clarity of the specification and thus is less useful for claim construction purposes.” Id. As a
result, courts generally require that “a patent applicant [] clearly and unambiguously express
surrender of subject matter” to disavow claim scope during prosecution. Voda v. Cordis Corp.,
536 F.3d 1311, 1321 (Fed. Cir. 2008) (quoting Sorensen v. Int’l Trade Comm’n, 427 F.3d 1375,
1378 (Fed. Cir. 2005)).
D.

Extrinsic Sources

Extrinsic evidence consists of “all evidence external to the patent and prosecution
history, including expert and inventor testimony, dictionaries, and learned treatises.” Phillips,
415 F.3d at 1317. It “can help educate the court regarding the field of the invention and can help

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the court determine what a person of ordinary skill in the art would understand claim terms to
mean.” Id. at 1319. However, extrinsic evidence suffers from a number of defects, including its
independence from the patent, potential bias, and varying relevance. Id. at 1318-19. Such
evidence is therefore “unlikely to result in a reliable interpretation of patent claim scope unless
considered in the context of the intrinsic evidence,” and courts may consider, or reject, such
evidence at their discretion. Id. at 1319.
E.

Indefiniteness

Section 112 of the Patent Act provides that “[t]he specification shall conclude with one or
more claims particularly pointing out and distinctly claiming the subject matter which the
applicant regards as his invention.” 35 U.S.C. § 112, ¶ 2. It follows that, as a condition of
validity, each patent claim must be sufficiently definite that “one skilled in the art would
understand the bounds of the claim when read in light of the specification.” Exxon Research and
Eng’g Co. v. United States, 265 F.3d 1371, 1375 (Fed. Cir. 2001). A claim is not indefinite as
long as its meaning is “discernible, even though the task [of claim construction] may be
formidable and the conclusion may be one over which reasonable persons will disagree.” Id. at
1375. Rather, a claim is invalid for indefiniteness only if it is “insolubly ambiguous, and no
narrowing construction can properly be adopted.” Id. at 1378.
Claim indefiniteness is an issue of law to be decided by the court. Enzo Biochem, Inc. v.
Applera Corp., 599 F.3d 1325, 1331 (Fed. Cir. 2010). While “a court may consider or reject
certain extrinsic evidence in resolving disputes en route to pronouncing the meaning of claim
language, the court is not crediting certain evidence over other evidence or making factual
evidentiary findings. Rather, the court is looking to the extrinsic evidence to assist in its

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construction of the written document.” Exxon Research, 265 F.3d at 1376 (internal quotations
omitted). Because indefiniteness renders a claim invalid, it must be proved by clear and
convincing evidence to overcome the presumption of validity. Halliburton Energy Servs., Inc. v.
M-I LLC, 514 F.3d 1244, 1249 (Fed. Cir. 2008); see also Exxon Research, 265 F.3d at 1380
(“[C]lose questions of indefiniteness . . . are properly resolved in favor of the patentee.”).
III.

Analysis
The proposed constructions of the disputed terms in the ’737 and ’927 patents are as

follows:

CLAIM TERM

ÖSSUR’S PROPOSED
CONSTRUCTION

iWalk’S PROPOSED
CONSTRUCTION

“gait pattern(s) or
event(s)”

“detectable series of natural
ankle movements during
locomotion or normal ankle
functions during
nonlocomotion”

indefinite

“ankle-angle
adjustments”

“ankle motion strategy for
changing the angle between the
foot unit and the lower limb
member”

“at least two changes to the angle
between the foot unit and the lower
limb member”

“processing module”

“computer-like component of
the ankle device”

“hardware logic, firmware
logic, or software instructions”

“substantially
mimicking the
movement of a
healthy ankle”

no construction necessary,
ordinary meaning

indefinite

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“subsequent gait
cycles”

no construction necessary,
ordinary meaning; or “later gait
cycles”

“gait cycles after the at least [sic]
one gait cycle”

“corresponding to [a
/ the] determined gait
pattern or event”

no construction necessary,
ordinary meaning

“corresponding to the gait pattern
or event determination made with
the data”

“position”

no construction necessary,
ordinary meaning

“location relative to ground”

“movement”

no construction necessary,
ordinary meaning

“change of position in time”

“state transition is
detected from the
determined gait
pattern or event to a
different gait pattern
or event”

“change from a first defined
gait pattern or event to a second
defined gait pattern or event”

“change is detected from one
determined gait pattern or
event to another determined
gait pattern or event”

“relaxed position”

no construction necessary,
ordinary meaning; or
“non-walking posture (such as
sitting, crossing legs,
reclining, lying down,
crawling, leaning, etc.)”

“sitting position”

“configurable
element”

“parameter”

indefinite

“automatically
adjusting”

no construction necessary,
ordinary meaning

“changing from one state to another
state based on the processed data”

A.

“Gait Pattern(s) or Event(s)”

The term “gait pattern(s) or event(s)” appears in claims 1 and 22 of the ’737 patent. Its
use in the following passage from claim 1 is typical:
processing the data with a processing module to determine if the data corresponds to one
of a plurality of defined gait patterns or events, wherein information defining said
plurality of gait patterns or events is stored in a memory of the device; determining
ankle-angle adjustments corresponding to a determined gait pattern or event . . .
’737 Patent at col. 20 ll. 41-47 (emphasis added).
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1.

Indefiniteness

Rather than propose a construction for the term “gait pattern(s) or event(s),” iWalk
contends that the term is indefinite, and that it therefore renders claims 1 and 22 of the ’737
patent invalid. As set forth above, in order to be valid, a patent claim must be sufficiently
definite that “one skilled in the art would understand the bounds of the claim when read in light
of the specification.” Exxon Research, 265 F.3d at 1375. Because all patents are presumed
valid, and a finding of indefiniteness renders a claim invalid, indefiniteness must be proved by
clear and convincing evidence. Halliburton, 514 F.3d at 1249.
There is an ambiguity that must be resolved at the outset that the parties have not directly
addressed, although their briefing reflects the issue: whether the word “gait” modifies both
“patterns” and “events.”2 That ambiguity, however, can be readily resolved by looking to the
patent as a whole, including the specification, which is the approach endorsed by the Federal
Circuit. See Scholle Corp. v. Packaging Sys., 2001 U.S. App. LEXIS 11772, 12-13 (Fed. Cir.
2001) (looking to the specification to determine whether the term “substantially” modified both
“removed and excluded” or just one); Lemelson v. Champion Spark Plug Co., 1992 U.S. App.
LEXIS 17184 (Fed. Cir. 1992) (taking the same approach). In context, the word “gait” clearly is
intended to modify only the word “patterns.” Although there could be such a thing as a “gait
event” (for example, a change in the angle of the foot), in context “events” are clearly intended
to be functions that occur when a person is not walking, such as “sitting,” “standing up,” or
“neutral.”

2

This type of ambiguity is sometimes referred to as the “Green Eggs and Ham” problem, after the
children’s book by Dr. Seuss. In the book, it is unclear from the text whether eggs and ham are both green, or the
eggs alone; the illustrations make clear, however, that both are green.

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As to the parties’ formal arguments on indefiniteness, iWalk contends that the term “gait
pattern(s) or event(s)” is indefinite because it cannot be construed in such a way that it
encompasses all of the “gait patterns or events” disclosed in the specification to the ’737 patent.
iWalk points to examples of “gait patterns or events” disclosed in the specification that do not fit
within either category of Össur’s proposed claim construction. According to iWalk, examples
such as “adjust heel height,” “off,” “heel height calibration,” “sensor calibration,” “neutral,”
“relax,” and “pants,” are neither “natural ankle movements during locomotion” nor “normal
ankle functions during nonlocomotion.” iWalk contends that there is, in fact, no possible way to
define the term so that it encompasses all of the examples disclosed in the specification, and the
term is therefore indefinite.
iWalk’s argument is flawed for a number of reasons. First, iWalk’s focus on Össur’s
proposed construction is misguided. The focus of the inquiry is on the claim term itself, not
either party’s proposed construction of it. iWalk must prove that the claim term is
“irreconcilable” with the specification, not that Össur’s proposed construction is inconsistent
with disclosed examples. See Skyhook Wireless, Inc. v. Google, Inc., 2012 WL 4076180, *12
(D. Mass. 2012). Furthermore, the fact that Össur’s proposed construction may not encompass
all the disclosed examples, even if proved, is not clear and convincing evidence that no
construction of the term whatsoever could encompass them. Finally, attorney argument, without
more, is generally not considered clear and convincing evidence sufficient to overcome the
presumption of validity. See, e.g., WesternGeco LLC v. ION Geophysical Corp., 876 F. Supp. 2d
857, 875 (S.D. Tex. 2012) (“Defendants’ unsupported attorney argument fails to prove
indefiniteness by clear and convincing evidence.”); Cacace v. Meyer Mktg. Co., 812 F. Supp. 2d

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547, 559-60 (S.D.N.Y. 2011) (ruling that claim term is not indefinite and explaining that “mere
attorney argument is insufficient to establish invalidity based on indefiniteness”).
The Federal Circuit has held that a claim term is indefinite where “a person of ordinary
skill in the art could not determine [its] bounds.” Halliburton, 514 F.3d at 1249. In response to
iWalk’s indefiniteness contentions, Össur offered the declaration of its expert, Dr. Steven A.
Gard. Dr. Gard also testified at the Markman hearing before this Court. In both his written
statement and live testimony, Dr. Gard offered the opinion that “a person of ordinary skill in the
art would have understood that the detectable ‘gait patterns or events’ are the series of natural
ankle movements during locomotion, or the normal ankle functions during non-locomotion.”
(See Gard Dec. at ¶ 20). iWalk, the party with the burden of proving indefiniteness, offered no
competing expert testimony as evidence of indefiniteness. Instead, it relied on the arguments
recited above and on their cross-examination of Dr. Gard.
Although (as explained in further detail below) the Court is not entirely convinced that
Össur’s proposed construction is correct, iWalk has not met its burden of proving that the term
“gait pattern(s) or event(s)” is indefinite. Indeed, the record evidence suggests that a person of
ordinary skill in the art would, in fact, be able to understand the term. Accordingly, the Court
finds that the term “gait pattern(s) or event(s)” is not indefinite.
2.

Claim Construction

Össur proposes to define the term “gait pattern(s) or event(s)” as “detectable series of
natural ankle movements during locomotion or normal ankle functions during nonlocomotion.”
Because iWalk contends that the term is indefinite, it proposes no alternative construction.
As support for its construction, Össur cites claim 22 and the specification of the ’737

17

patent. Specifically, Össur contends that claim 22 lists examples of “gait patterns” and “events.”
According to Össur, the examples that describe types of locomotion are “gait patterns,” and the
examples that describe normal ankle functions that occur while the device is not moving (in
other words, during nonlocomotion) are “events.” The list of claim 22 comprises the following:
“stance, level ground walking, ascending stairs, descending stairs, incline, decline, sitting down,
sitting, standing up, adjust heel height, off, heel height calibration, sensor calibration, neutral,
relax, and pants.” ’737 Patent at col. 22 ll. 3-8. Össur also contends that in the specification of
the ’737 patent Figure 10, Table 1, and Table 2 provide examples of “gait patterns” and
“events.” Those figures and tables include the same examples as claim 22 with corresponding
ankle-angles and ankle-motion descriptors.
According to Össur, “level ground walking,” “ascending stairs,” “descending stairs,”
“incline,” and “decline” are “gait patterns,” or, in the words of the proposed construction,
“natural ankle movements during locomotion.” It contends that “stance,” “sitting,” “standing
up,” “adjust heel height,” “off,” “heel height calibration,” “sensor calibration,” “neutral,”
“relax,” and “pants” are “events,” or, in the words of the proposed construction, “normal ankle
functions during nonlocomotion.”
iWalk contends that the examples cited by Össur do not fit into the categories created by
its own proposed definition. In its briefing, and at oral argument, iWalk made much of the fact
that examples like “off,” “heel height calibration,” and “adjust heel height” are not functions of a
normal human ankle. However, Össur’s proposed construction does not require that these
“events” be normal for a biological human ankle. These examples can fairly be said to fit in the
proposed category of “normal ankle functions” for a mechanical prosthetic ankle. To the extent

18

that some of the examples of “gait patterns” are not “natural ankle movements,” that flaw can be
easily remedied by replacing the descriptor “natural” with the word “normal” in reference to the
“ankle movements” as well.
iWalk also cites to the prosecution history, specifically Össur’s communications with the
patent office and amendments to claim 23, which formerly described only “gait patterns.” iWalk
contends that because the amendment to claim 23 that included the addition of the word “events”
was accompanied by the addition of only one new example— “relax”—the other examples must
all be classified as “gait patterns.” iWalk’s heavy reliance on that evidence is misplaced. As
described above, “because the prosecution history represents an ongoing negotiation between the
PTO and the applicant, rather than the final product of that negotiation, it often lacks the clarity
of the specification and thus is less useful for claim construction purposes.” Phillips, 415 F.3d at
1323. The Court is not convinced that Össur’s amendment to claim 23 during the patent
prosecution is an appropriate indicator of the meaning of the term “gait pattern(s) or event(s)” as
it was ultimately used in the patent.
Accordingly, the Court will construe the term “gait pattern(s) or event(s)” to mean
“detectable series of normal ankle movements during locomotion or normal ankle functions
during nonlocomotion.”
B.

“Ankle-Angle Adjustments”

The term “ankle-angle adjustments” appears in claims 1 and 34 of the ’737 patent. Its
use in the following passage from claim 1 is typical:
. . . adjusting the device based on the determined ankle-angle adjustments
corresponding to the determined gait pattern or event, wherein the adjusting comprises
actuating the at least [sic] one actuator to move the lower limb member relative to the
foot unit in a manner substantially mimicking movement of a healthy ankle, said
19

ankle-angle adjustments being applied over a swing phase of subsequent gait cycles
until a state transition is detected from the determined gait pattern or event to a different
gait pattern or event.
’737 Patent at col. 20 ll. 48-57 (emphasis added).
iWalk does not contend that this term is indefinite, and the parties generally agree that
“ankle-angle adjustments” involve changing the angle between the foot and the lower limb
member. The parties disagree as to whether the fact that the word “adjustments” is plural
requires there to be at least two changes to the ankle-angle. iWalk contends that the plural
necessarily indicates at least two changes to the ankle-angle. Össur contends that because many
of the examples of “ankle-angle adjustments” disclosed in claim 34 involve only one change to
the ankle-angle, the term must not be construed to require two or more changes and thereby
exclude those claimed examples.
Looking first to the language of the claims themselves, a number of examples of “ankleangle adjustments” are provided in claim 34. That claim describes certain “ankle-angle
adjustments” as follows:
. . . ankle-angle adjustments comprise at least one of the following: toe clearance; user
set point; set heel height; relax ankle; a desired degree of dorsiflexion; a desired degree
of plantarflexion; ten degrees of dorsiflexion; five degrees of dorsiflexion; seven and a
half degrees of dorsiflexion; 20 degrees of plantarflexion; an ankle angle associated with
an incline angle threshold level; an ankle angle associated with a decline angle threshold
level; an ankle angle associated with an incline angle of five degrees; an ankle angle with
an incline angle of two and a half degrees; an ankle angle associated with a decline angle
of five degrees; and an ankle angle associated with a decline angle of two and a half
degrees.
’737 Patent at col. 23 ll. 5-17. Össur contends that of those sixteen examples of “ankle-angle
adjustments,” none involve more than one change to the angle between the foot and the lower
limb member. Figure 10 and Table 2 of the specification of the ’737 patent recite the same

20

examples of “ankle-angle adjustments” and indicate the precise single adjustment required for
each of them. This is strong evidence indicating that the term, as it is used in the claims, does
not require two or more changes to the ankle-angle. Vitronics Corp. v. Conceptronic, Inc., 90
F.3d 1576, 1583 (Fed. Cir. 1996) (holding that “an interpretation [that excludes a preferred
embodiment from the scope of the claims] is rarely, if ever, correct and would require highly
persuasive evidentiary support”).
iWalk emphasizes that in common usage a plural indicates more than one, and if Össur
wanted to refer to a singular ankle-angle adjustment, it could have easily done so by omitting the
letter “s.” Össur responds by suggesting that if it wanted to emphasize that “ankle-angle
adjustments” involved at least two changes, it would have described them as a “plurality of”
adjustments, rather than just using the plural. It is certainly the case that in common English
usage, a plural form of a noun indicates more than one, and it is not typical to precede the
modified noun with the phrase “plurality of” to convey that meaning. Accord Dayco Prods. v.
Total Containment, Inc., 258 F.3d 1317, 1328 (Fed. Cir. 2001) (indicating that the claim term
“recesses” can be “understood to mean a single recess” and explaining that “if the patentees had
wanted to require an insert means with more than one recess, it would have been natural to limit
the claimed invention to an insert means with a ‘plurality of recesses’”). However, as noted, the
Federal Circuit in Phillips strongly cautioned against the approach of importing common usage
definitions into claim construction. 415 F.3d at 1321. Relying on such definitions is warranted
only if no special meaning is apparent after reviewing the intrinsic evidence. Id. at 1314. The
intrinsic evidence here, as recited above, indicates that the term “ankle-angle adjustments”
includes actions that involve only a single change to the angle between the foot and the lower

21

limb member. Accordingly, the Court will construe it as such.
Össur’s proposed construction attempts to convey that the term describes actions that
involve one or multiple changes to the ankle-angle by using the word “strategy.” Specifically,
Össur urges that the term “ankle-angle adjustments” be construed as “ankle motion strategy for
changing the angle between the foot unit and the lower limb member.” The Court finds this
proposed construction unnecessarily confusing and not supported by the language of the claims.
Instead, the Court will adopt a construction that is more appropriately centered on the agreement
between the parties that “ankle-angle adjustments” involve the action of changing the angle
between the foot and the lower limb member.
Accordingly, the Court will construe the term “ankle-angle adjustments” to mean “a
change, or multiple changes, to the angle between the foot unit and the lower limb member.”
C.

“Processing Module”

The term “processing module” appears in claim 1of the ’737 patent and claim 1 of the
’927 patent. The term is used in substantially the same way in both claims. The relevant part of
claim 1 of the ’737 patent reads as follows:
. . . processing the data with a processing module to determine if the data corresponds to
one of a plurality of defined gait patterns or events, wherein information defining said
plurality of gait patterns or events is stored in a memory of the device . . .
’737 Patent at col. 20 ll. 41-45 (emphasis added).
The parties generally agree that the “processing module” is responsible for comparing
real-time data to stored memory. The dispute concerning this term concerns whether it covers
the entire central processing unit (“CPU”) of the prosthetic device or only certain modules within
the CPU. iWalk contends that the term “processing module” describes one of three types of

22

modules—“hardware logic, firmware logic, or software instructions.” Össur contends that the
term simply describes the CPU as a whole, and proposes to construe the term to mean a
“computer-like component of the ankle device.”
Össur’s proposed construction finds greater support in the intrinsic evidence. First, claim
1 of the ’737 patent, when read in conjunction with the specification, seems to equate a
“processing module” with a CPU. As recited above, claim 1 indicates that the ankle device
processes data with a “processing module to determine if the data [from at least one sensor]
corresponds to one of a plurality of defined gait patterns or events.” ’737 Patent at col. 20 ll. 4144. The specification of the ’737 patent explains that same series of events by stating that “the
CPU processes information relating to the gait of the user, such as information received from the
sensor module, [and] determines locomotion type (i.e., gait pattern).” Id. at col. 13 ll. 61-64.
In addition, Figure 9 of the ’737 patent specification suggests that the CPU is a
processing module, which corresponds to, and works in conjunction with, the ankle unit’s
“sensor module,” “interface module,” “power module,” and “control drive module.” Id. at fig. 9.
The specification further states that physical memory, which can be stored internally or
externally, is “access[ed] by another computing device or a computer processor.” Id. at col. 16
ll. 12-15. The way that the terms “CPU,” “computing device,” and “computer processor” are
used in the specification seem to suggest that they are synonymous with the “processing
module.”
On other hand, another part of the specification provides the basis for iWalk’s proposed
construction. The specification indicates that the “CPU includes modules that comprise logic
embodied in hardware or firmware, or that comprise a collection of software instructions written

23

in a programming language.” Id. at col. 15 ll. 51-54 (emphasis added). Össur contends that
confining the term “processing module” to these sub-components of the CPU inappropriately
imports a limitation into the claim from a specific embodiment. According to Össur, the relevant
characteristic is the existence of, and reliance on, the CPU itself, not the specific inner workings
of the CPU.
Looking to the prosecution history to resolve the dispute, the PTO essentially adopted
Össur’s construction of the term. Specifically, the PTO cited to two prior art references that
disclosed the use of a “microcomputer” and contended that those references anticipated claims
that recited a “processing module,” thus indicating that the PTO understood “processing
module” to mean something like a microcomputer. (See Zovko Dec. at Exs. E, H, and I).
iWalk also contends that the use of the phrase “computer-like,” as in Össur’s prosed
construction, would render the claim indefinite. This Court disagrees, but, in the abundance of
caution, will add clarifying language in adopting Össur’s proposed construction.
Accordingly, the Court will construe the term “processing module” to mean a “computerlike component, or CPU, of the ankle device.”
D.

“Substantially Mimicking the Movement of a Healthy Ankle”

The term “substantially mimicking the movement of a healthy ankle” appears in claim 1
of the ’737 patent. The relevant part of the claim reads as follows:
. . . adjusting the device based on the determined ankle-angle adjustments corresponding
to the determined gait pattern or event, wherein the adjusting comprises actuating the at
least [sic] one actuator to move the lower limb member relative to the foot unit in a
manner substantially mimicking movement of a healthy ankle . . .
’737 Patent at col. 20 ll. 48-53 (emphasis added).

24

1.

Indefiniteness

Rather than propose a construction for the term “substantially mimicking the movement
of a healthy ankle,” iWalk contends that the term is indefinite, and that it therefore renders claim
1 of the ’737 patent invalid. As outlined above, in order to be valid, a patent claim must be
sufficiently definite that “one skilled in the art would understand the bounds of the claim when
read in light of the specification.” Exxon Research, 265 F.3d at 1375. Because all patents are
presumed valid, and a finding of indefiniteness renders a claim invalid, indefiniteness must be
proved by clear and convincing evidence. Halliburton, 514 F.3d at 1249.
iWalk contends that the term “substantially mimicking the movement of a healthy ankle”
is indefinite because the patent does not disclose information about the movement of a healthy
ankle during all of the “gait patterns or events” described in the claims. iWalk contends that, as
a result, a person of ordinary skill in the art would not be able to evaluate whether a device
“substantially mimics movement of a healthy ankle” during each and every action of the wearer.
iWalk further contends that the intrinsic evidence—specifically, claim 23 and Figure 8 of the
specification of the ’737 patent—describes the characteristic movements of a healthy ankle in
contradictory fashion. According to iWalk, claim 23 suggests that during the swing phase the
foot moves first to a dorsiflexion position and then to a plantarflexion position, while Figure 8
depicts a swing phase wherein the foot does not ever enter a dorsiflexion position. iWalk goes
on to describe other instances where the patent claims and specification allegedly do not
accurately, or adequately, describe the movement of a healthy ankle during certain actions.
iWalk contends that those alleged deficiencies in describing the movement of a healthy
ankle, along with variations in gait patterns between individual persons, make it impossible for

25

one skilled in the art to judge whether or not a device “substantially mimics” a healthy ankle.
See Halliburton, 514 F.3d at 1255 (“when a proposed construction requires that an artisan make
a separate infringement determination for every set of circumstances in which the composition
may be used, and when such determinations are likely to result in differing outcomes (sometimes
infringing and sometimes not), that construction is likely to be indefinite”). iWalk further
contends that the use of the word “substantially” renders the claim indefinite because the patent
provides no guidance as to the degree of closeness required to meet this standard. See KLATencor Corp. v. Xitronix Corp., 2011 WL 318123, *3 (W.D. Tex. Jan. 31, 2011) (holding
“substantially maximizing” indefinite because “there is no standard for determining what is
substantially maximizing in the patent itself”).
iWalk has again failed to meet its burden with regards to proving indefiniteness. First,
iWalk’s apparent insistence that the patent teach the characteristic movements of a healthy ankle
for each of the “gait patterns or events” is misguided. A patent need not define every term or
reference contained in its claims in order to be definite; it need only provide sufficient
description so that “a person of ordinary skill in the art could [] determine [its] bounds.”
Halliburton, 514 F.3d at 1249. Accordingly, if a person of ordinary skill in the art understands
what the characteristic movements of a healthy ankle would be for the various actions disclosed
in the ’737 patent, the patent need not define all of those characteristics.
Here, Össur’s expert, Dr. Gard, offered the opinion, in both his written statement and live
testimony, that “[a] person of ordinary skill in the art . . . would have understood that the
movement of a healthy ankle during various types of gait patterns or events (e.g., walking,
ascending stairs, descending stairs, etc.) were well known and fully characterized in the field of

26

lower limb prosthetics.” (See Gard Dec. at ¶ 30). iWalk, the party with the burden of proving
indefiniteness, made reference in its briefing to the same text by Jacquelin Perry, M.D., relied on
by Össur, but offered none of its own evidence or competing expert testimony as to
indefiniteness.3 Instead, it relied on attorney arguments and on its cross-examination of Dr. Gard
in an attempt to persuade the Court that the Perry reference did not teach those skilled in the art
what “substantially mimicking a healthy ankle” would require. Again, attorney argument,
without more, is generally not considered clear and convincing evidence sufficient to overcome
the presumption of validity. See, e.g., WesternGeco LLC, 876 F. Supp. 2d at 875; Cacace, 812
F. Supp. 2d at 559-60.
Furthermore, the patent’s use of the modifier “substantially” does not render the term
indefinite. The Federal Circuit very recently confirmed that the use of such modifiers do not
render claims per se indefinite. Deere & Co. v. Bush Hog, LLC, 703 F.3d 1349, 1359 (Fed. Cir.
2012) (remarking that “[t]his court has repeatedly confirmed that relative terms such as
‘substantially’ do not render patent claims so unclear as to prevent a person of skill in the art
from ascertaining the scope of the claim”). iWalk offered no affirmative evidence to establish
that the use of the modifier here is confusing to those skilled in the art.
Although, as explained in further detail below, the Court is not entirely convinced that
the term is so easily understood that it need not be construed, iWalk has not met its burden of
proving that the term “substantially mimicking the movement of a healthy ankle” is indefinite.
Indeed, the record evidence suggests that a person of ordinary skill in the art would, in fact, be
able to understand the term. Accordingly, the Court finds that the term “substantially mimicking

3

JACQUELIN PERRY, GAIT ANALYSIS: NORMAL AND PATHOLOGICAL FUNCTION (1992).

27

the movement of a healthy ankle” is not indefinite.
2.

Claim Construction

Össur contends that the term “substantially mimicking the movement of a healthy ankle”
can be readily understood according to its ordinary meaning and need not be given special
construction by the Court. Because iWalk contends that the term is indefinite, it also proposes
no specific construction of the term, but does request that the Court’s construction exclude a
device that uses a stop mechanism limiting the range of movement.
As noted, the Court is not required to provide additional language construing a claim if
its ordinary meaning can be readily understood by a layperson and adopting it would resolve the
parties’ dispute concerning interpretation. See O2 Micro, 521 F.3d at 1361; see also
CardioFocus, Inc. v. Cardiogenesis Corp., 827 F. Supp. 2d 36, 41 (D. Mass. 2011) (holding that
when “claim terms do not implicate any special knowledge possessed by a person in the art and,
thus, should be given their ordinary meanings,” and the terms are not “ambiguous or
uncommon,” claim construction is not warranted); Finjan, 626 F.3d at 1206-07 (holding that the
district court did not err by not explicitly construing the term “addressed to a client” and relying
on its ordinary meaning); Phillips, 415 F.3d at 1314 (“In some cases, the ordinary meaning of
claim language as understood by a person of skill in the art may be readily apparent even to lay
judges, and claim construction in such cases involves little more than the application of the
widely accepted meaning of commonly understood words.”).
Here, it is not clear that the parties actually dispute the interpretation of the term
“substantially mimicking the movement of a healthy ankle.” To the extent that there is a dispute,
it seems to concern whether a device that utilizes a stop mechanism to restrict its movement can
“substantially mimic” a healthy ankle. However, to resolve this dispute would essentially

28

require the Court to make a summary judgment decision as to non-infringement, without
significant briefing on the issue. Accordingly, the Court will refrain from formally construing
the term.
Nonetheless, the Court is concerned that lay jurors’ general understanding of the term,
without further interpretation by the Court, might differ from the meaning given to it by those
skilled in the art. Accord Phillips, 415 F.3d at 1315-1317. This is of particular concern due to
the use of the modifier “substantially.” Accordingly, though the Court will not formally construe
the term, it will direct the parties to rely on Perry’s graphical depiction of healthy ankle
movement, adorned with lines of standard deviation, when presenting evidence as to whether
iWalk’s device “substantially mimic[s] the movement of a healthy ankle.”
E.

“Subsequent Gait Cycles”

The term “subsequent gait cycles” appears in claim 1 of the ’737 patent. The relevant
part of the claim reads as follows:
. . . said ankle-angle adjustments being applied over a swing phase of subsequent gait
cycles until a state transition is detected from the determined gait pattern or event to a
different gait pattern or event.
’737 Patent at col. 20 ll. 53-57 (emphasis added).
The parties’ dispute about the construction of this term concerns only whether the Court
should define the word “subsequent” and, if so, how.4 Össur contends that the entire term need
not be construed, but if the meaning of the word “subsequent” must be clarified, the Court
should define it as “later.” iWalk contends that the Court must construe the word “subsequent”
to mean “after at least one gait cycle” in order to firmly establish that the ankle-angle

4

The parties have agreed to a construction of the included term “gait cycle.”

29

adjustments described in claim 1 do not occur during the first gait cycle.
The plain language of the claim itself lends some support to iWalk’s proposed
construction, but is ultimately not clear enough to override the other intrinsic evidence. Claim 1
teaches a “method for controlling an ankle device” that comprises a number of steps. The first of
those steps involves “monitoring, with at least one sensor, at least one of position and movement
of an ankle device associated with a limb throughout at least one gait cycle.” ’737 Patent at col.
20 ll. 34-36 (emphasis added). The second step involves “generating data indicative of the at
least one of position and movement throughout the at least [sic] one gait cycle.” Id. at col. 20 ll.
39-40 (emphasis added). The final step of the method includes the term at issue and teaches
making ankle-angle adjustments and continuing to apply them “over a swing phase of
subsequent gait cycles until a state transition is detected from the determined gait pattern or
event to a different gait pattern or event.” Id. at col 20 ll. 54-57 (emphasis added).
iWalk contends that the claim’s progression through these steps indicates that the
“subsequent gait cycles” are gait cycles after the “at least [sic] one gait cycle” in which the
monitoring and data generation occurred. However, iWalk assumes a specific internal reference
that is not obvious, and thereby reads too much into the limitation of the final step and
misinterprets its purpose. Properly read, the final step, in which the ankle-angle adjustments are
to be “applied over a swing phase of subsequent gait cycles,” is meant to emphasize not when
the ankle-angle adjustments are first applied, but rather the duration over which those
adjustments are continually applied. That is made evident not only by the language defining that
duration—“until a state transition is detected from the determined gait pattern or event to a
different gait pattern or event”—but also by the language of the earlier part of the step that

30

actively describes “adjusting the device based on the determined ankle-angle adjustments
corresponding to the determined gait pattern or event.” Id. at col. 20 ll. 55-57, 48-50.
Furthermore, considering the repeated use of the phrase “at least one gait cycle,” it seems likely
that if the patentee intended to limit the claim to devices that do not make adjustments during the
first gait cycle, it would have specifically made reference to it using that same language.
Össur, in turn, points to the specification of the ’737 patent, which states that “[i]n one
embodiment of the invention, the control system detects the gait of the user and adjusts the ankle
device accordingly while the ankle device is in a swing phase of the first step.” Id. at col. 12 ll.
53-56. It goes on to describe other embodiments where “there may be a latency period in which
the control system requires one or two strides before being able to accurately determine the gait
of the user and to adjust the ankle device appropriately.” Id. at col. 12 ll. 57-60. Össur invokes
the principle that “[a] claim construction that excludes the preferred embodiment is rarely, if
ever, correct” to suggest that Court must not construe the word “subsequent” so as to exclude
adjustments made in the first gait cycle. Adams Respiratory Therapeutics, Inc. v. Perrigo Co.,
616 F.3d 1283, 1290 (Fed. Cir. 2010).
As noted, “[t]he construction that stays true to the claim language and most naturally
aligns with the patent’s description of the invention will be, in the end, the correct construction.”
Phillips at 1316 (citing Renishaw PLC v. Marposs Societa’ per Azioni, 158 F.3d 1243, 1250
(Fed. Cir. 1998). Here, construing the word “subsequent” to mean “later,” but not confining the
term “subsequent gait cycles” to “gait cycles after the at least [sic] one gait cycle,” conforms
with the language of the claim and does not exclude the embodiments disclosed in the
specification. Furthermore, such a construction will not create an internal reference within claim

31

1 that could potentially confuse the jury.
Accordingly, the Court will construe the term “subsequent gait cycles” to mean “later
gait cycles.”
F.

“Corresponding to [a / the] Determined Gait Pattern or Event”

The term “corresponding to [a/the] determined gait pattern or event” appears in various
iterations throughout claim 1 of the ’737 patent. The pertinent part of claim 1 reads as follows:
. . . processing the data with a processing module to determine if the data corresponds to
one of a plurality of defined gait patterns or events, wherein information defining said
plurality of gait patterns or events is stored in a memory of the device; determining
ankle-angle adjustments corresponding to a determined gait pattern or event; and
adjusting the device based on the determined ankle-angle adjustments corresponding to
the determined gait pattern or event . . .
’737 Patent at col. 20 ll. 41-47 (emphasis added).
The included term “gait pattern or event” has already been construed. The only further
dispute as to this term concerns whether the Court should define the word “determined” and, if
so, how. Össur contends that the term need not be construed, and the Court should simply adopt
its plain meaning. iWalk contends that the Court must construe the term in order to firmly
establish that the “gait pattern or event” is “determined” based on the data acquired by, and
stored in, the device.
As support for its proposed construction, iWalk again refers to the steps disclosed in
claim 1. As recited above, the first two of those steps involve “monitoring . . . [the] position and
movement of an ankle device . . . and generating data” based on that monitoring. ’737 Patent at
col. 20 ll. 34-36, 39-40. The next step teaches “processing the data with a processing module to
determine if the data corresponds to one of a plurality of defined gait patterns or events.” Id. at
41-43. iWalk thus asks the Court to construe the term “corresponding to [a/the] determined gait
32

pattern or event” to mean “corresponding to the gait pattern or event determination made with
the data” in order to make clear to the jury that any time a step of claim 1 mentions a
“determined” gait pattern or event it refers to a gait pattern or event determination made via the
“processing” step just described.
Össur responds first by stressing the argument that the words “corresponding” and
“determined” are easily understood by a lay jury and thus need no further construction. Össur
goes on to contend that iWalk’s proposed construction is not only unnecessary, but also
improperly rewrites the claim to import an extrinsic limitation.
Again, the court may not import limitations into the claims that have no basis in the
language of the claims themselves, whether those limitations come from the specification or
from some other extrinsic source. See Phillips, 415 F.3d at 1323 (holding that courts must not
“import[] limitations from the specification into the claim”); see also DSW, Inc. v. Shoe Pavilion,
Inc., 537 F.3d 1342, 1348 (Fed. Cir. 2008) (reversing claim construction where a district court
“improperly read into [the claims] a new limitation not required by the claim language”).
However, the Court finds that adopting iWalk’s proposed construction of the term at issue would
not violate that principle. iWalk’s proposed construction is based on the language of the claim
itself and the progression of disclosed method steps within the claim. The internal reference
between the “determined” gait pattern or event and the earlier description of how it is determined
has a strong basis in the language of the claim. There is no other description, in the claim or in
the specification, of how a gait pattern or event might be “determined” other than by processing
the data acquired by the device. Adopting iWalk’s proposed construction of this term would not
exclude any of the embodiments disclosed in the specification. The Court also agrees with

33

iWalk that a lay juror may not recognize that the phrase “determined gait pattern or event” as
used in later steps of claim 1 is meant to refer back to the earlier steps of claim1 that teach how
such a determination is made.
Accordingly, the Court will construe the term “corresponding to [a/the] determined gait
pattern or event” to mean “corresponding to [a/the] gait pattern or event determination made
with the data.”
G.

“Position” and “Movement”

The terms “position” and “movement” appear in claim 1 of the ’737 patent and claims 1,
5, and 7 of the ’927 patent. Their general use in claim 1 of the ’737 patent encompasses the
more specific references in the later claims:
. . . monitoring, with at least one sensor, at least one of position and movement of an
ankle device associated with a limb throughout at least one gait cycle, wherein the device
comprises a foot unit, a lower limb member, and at least one actuator . . .
’737 Patent at col. 20 ll. 34-38 (emphasis added).
Össur contends that the terms “position” and “movement” can be readily understood
according to their ordinary meanings and need not be given special construction by the Court.
iWalk contends that the terms have specific meanings in the context of the invention that must be
explained to the jury to avoid potential confusion. iWalk proposes that the Court construe the
term “position” to mean “location relative to the ground,” and the term “movement” to mean
“change of position in time.”
A court is not required to provide additional language construing a claim if its ordinary
meaning can be readily understood by a layperson and adopting it would resolve the parties’
dispute concerning interpretation. See O2 Micro, 521 F.3d at 1361; see also CardioFocus, Inc.

34

v. Cardiogenesis Corp., 827 F. Supp. 2d 36, 41 (D. Mass. 2011) (holding that when “claim terms
do not implicate any special knowledge possessed by a person in the art and, thus, should be
given their ordinary meanings,” and the terms are not “ambiguous or uncommon,” claim
construction is not warranted); Finjan, 626 F.3d at 1206-07 (holding that the district court did
not err by not explicitly construing the term “addressed to a client” and relying on its ordinary
meaning); Phillips, 415 F.3d at 1314 (“In some cases, the ordinary meaning of claim language as
understood by a person of skill in the art may be readily apparent even to lay judges, and claim
construction in such cases involves little more than the application of the widely accepted
meaning of commonly understood words.”).
Although the terms “position” and “movement” are not complicated, they can describe a
great variety of spatial relationships and actions. iWalk’s construction attempts to confine the
terms to descriptors of the ankle device as a whole, not of any constituent part. As support for its
limiting construction of “position,” iWalk cites the specification of the ’737 patent, which
describes the information that the sensor module may collect including “the position of the ankle
device with respect to the ground.” ’737 Patent at col. 12 ll. 18-20. iWalk contends that the
quoted specification language is the only description of “position” in the patent. As support for
its limiting construction of “movement,” iWalk cites only the American Heritage College
Dictionary, which defines “movement” as, among other things, “a change in place or position.”
Again, a court must not import limitations into the claims that have no basis in the
language of the claims themselves, whether those limitations come from the specification or
from some other extrinsic source. See Phillips, 415 F.3d at 1323 (holding that courts must not
“import[] limitations from the specification into the claim”). Furthermore, the Federal Circuit in

35

Phillips strongly cautioned against the approach of importing limitations from dictionary
definitions into claim construction. 415 F.3d at 1321. iWalk provides no compelling reason
why the terms “position” and “movement” should be defined as narrowly as it contends. There
is also no evidence that lay jurors would be confused by the terms or have a different
understanding than those skilled in the art. See Phillips, 415 F.3d at 1315-1317.
Accordingly, the Court will not construe the terms “position” and “movement” beyond
attributing to them their ordinary meanings.
H.

“State Transition Is Detected from the Determined Gait Pattern or Event to
a Different Gait Pattern or Event”

The term “state transition is detected from the determined gait pattern or event to a
different gait pattern or event” appears in claim 1 of the ’737 patent. The relevant part of the
claim reads as follows:
. . . said ankle-angle adjustments being applied over a swing phase of subsequent gait
cycles until a state transition is detected from the determined gait pattern or event to
a different gait pattern or event.
’737 Patent at col. 20 ll. 53-57 (emphasis added).
The parties appear to agree that the included term “state transition” simply means
“change.” Indeed, they appear to generally agree that the entire term at issue describes a change
from one gait pattern or event to another. The dispute between the parties concerns the included
term “different” and whether the claim requires that the new gait pattern or event be
“determined” according to the method described in the other parts of claim 1. iWalk contends
that it must be so “determined,” and thus proposes to construe the term “different” to mean
“another determined.” iWalk then proposes to construe the entire term at issue to mean “change
is detected from one determined gait pattern or event to another determined gait pattern or
36

event.” Össur contends that iWalk’s proposed construction impermissibly narrows the claim,
and instead proposes to construe the term “different” to mean “second defined.” Össur then
proposes to construe the entire term at issue to mean “change from a first defined gait pattern or
event to a second defined gait pattern or event.” Upon careful examination of the intrinsic
evidence, the Court is not convinced that either of the proposed constructions is entirely
appropriate.
iWalk contends that the claim language, the specification, and the file history teach no
other way to detect a “different gait pattern or event” other than to “determine” it by carrying out
the steps of claim 1. As a result, iWalk urges the Court to make clear to the jury that the claim
requires the device to make a second determination in order to engage in a state transition.
However, Össur responds that the claim language includes no such requirement, and thus
importing it during claim construction would be improper.
Claim 1 of the ’737 patent uses both the phrase “determined gait pattern or event” and the
phrase “different gait pattern or event.” It uses those phrases in different contexts, to describe
different steps in the method. For example, the claim teaches the step of “determining
ankle-angle adjustments corresponding to a determined gait pattern or event.” This step thus
requires the device to “determine” a specific gait pattern or event and adjust the ankle-angle
according to that determination. In contrast, the claim employs the term “different gait pattern or
event” when it describes the duration over which ankle-angle adjustments are continually
applied, indicating that those adjustments are no longer applied when a change is “detected from
the determined gait pattern or event to a different gait pattern or event.” This suggests that the
adjustments cease to be applied when the gait pattern or event is detected to be generally

37

different, not when a specific new gait pattern or event is detected. Not coincidentally, iWalk
cites no other intrinsic or extrinsic evidence to support its proposed construction, which would
require that a specific determination be made. Finally, it is clear from the prolific use of the
word “determined” throughout claim 1 that if the drafter wanted to require that a new,
“different” gait pattern or event be specifically “determined,” he could have used that
descriptor.5 Accordingly, the Court will not adopt iWalk’s proposed construction.
Unfortunately, Össur also attempts to rewrite the claim with its proposed construction.
Specifically, Össur replaces both the included terms “determined” and “different” with the word
“defined.” As support for this construction, Össur cites to the prosecution history. However,
none of the language cited by Össur uses the word “defined” to describe a “gait pattern or
event.” Although it might not impermissibly expand the claim’s scope, the use of “defined” here
in construing the term has the potential to confuse the jury. Furthermore, the word “different” is
readily understood by lay persons and has no special meaning in this context. Accordingly, the
Court will not adopt Össur’s proposed construction.
Although neither party specifically requested such an interpretation, the ordinary
meaning of the included term “different” can be readily understood by a layperson. See
CardioFocus, Inc. v. Cardiogenesis Corp., 827 F. Supp. 2d 36, 41 (D. Mass. 2011) (holding that
when “claim terms do not implicate any special knowledge possessed by a person in the art and,
thus, should be given their ordinary meanings,” and the terms are not “ambiguous or
uncommon,” claim construction is not warranted). The word “different” does not imply that the

5

As Össur correctly points out, there is a presumption in claim construction that different words used in the
claims of the same patent are presumed to have different meanings. See CAE Screenplates, Inc. v. Heinrich Fiedler
GmbH & Co., 224 F.3d 1308, 1317 (Fed. Cir. 2000).

38

gait pattern or event be “determined,” as iWalk would prefer. Using the ordinary meaning
conforms to the claim language and Össur’s proposed construction, without adding the potential
for juror confusion. The Court will thus adopt the agreed-upon construction of “state transition”
to mean “change,” but will not otherwise construe the remainder of the term.
Accordingly, the Court will construe the term “state transition is detected from the
determined gait pattern or event to a different gait pattern or event” to mean “change is detected
from the determined gait pattern or event to a different gait pattern or event.”
I.

“Relaxed Position”

The term “relaxed position” appears in claim 1 and dependent claim 7 of the ’927 patent.
The term’s use in the following portion of claim 1 is typical:
. . . adjusting the prosthetic ankle device based on whether the user is in the relaxed
position, wherein adjusting the prosthetic ankle device comprises automatically adjusting
a configurable element of the prosthetic ankle device.
’927 Patent at col. 40 ll. 1-5 (emphasis added).
The parties’ dispute concerns whether the term “relaxed position” refers specifically and
exclusively to a sitting position, or whether it encompasses other “non-walking postures.” iWalk
contends that the language of claim 1 limits the term to mean only a “sitting position.” Össur
contends that the term is not so narrowly defined, and further contends that it can be readily
understood according to its ordinary meaning and need not be given special construction. In the
alternative, Össur proposes that the term be construed to mean “non-walking posture (such as
sitting, crossing legs, reclining, lying down, crawling, leaning, etc.).”
iWalk finds strong support for its proposed construction in the language of claim 1 of the
’927 patent. Claim 1 specifically describes “processing the data with a processing module to

39

determine whether the user is in a relaxed position, wherein the relaxed position is a sitting
position.” ’927 Patent at col. 39 ll. 65-67 (emphasis added). As Phillips indicated, the words of
the claims themselves are of paramount importance to the construction of terms included within
them. 415 F.3d at 1314. Philips further held that when “the specification . . . reveal[s] a special
definition given to a claim term by the patentee that differs from the meaning it would otherwise
possess . . . the inventor's lexicography governs.” Id. at 1316. That rule applies with equal, if
not greater, force to definitions included within the claims themselves.
In response, Össur points to the specification of the ’927 patent, which describes a
number of “relaxed position[s], such as sitting, crossing legs, reclining, lying down, crawling,
leaning, etc.” ’927 Patent at col. 34 ll. 20-23. Össur contends that to confine the term to refer
only to “sitting” would impermissibly add a new limitation to the claim. Össur further contends
that iWalk’s construction is improper because it would render “relaxed” mere surplusage in
claim 1 by giving it the same meaning as “sitting.” See Telemac Cellular Corp. v. Topp
Telecom, Inc., 247 F.3d 1316, 1325 (Fed. Cir. 2001) (rejecting a proposed construction that
would render a phrase as “mere surplusage”).
The language of claim 1 and the patent prosecution history suggests that iWalk’s
interpretation is in fact correct. Claim 1 refers to “processing the data with a processing module
to determine whether the user is in a relaxed position, wherein the relaxed position is a sitting
position; and adjusting the prosthetic ankle device based on whether the user is in the relaxed
position . . . ” ’927 Patent at col. 39 ll. 65-67, col. 40 ll. 1-2 (emphasis added). As that passage
indicates, the claim uses both the indefinite article “a” and the definite article “the” before the
term “relaxed position.” The “wherein” conjunction followed by the definite article suggests

40

that “the relaxed position” refers to a specific “relaxed position,” which is defined as “a sitting
position.” See Warner–Lambert Co. v. Apotex Corp., 316 F.3d 1348, 1356 (Fed. Cir. 2003) (“it
is a rule of law well established that the definite article ‘the’ particularizes the subject which it
precedes”); see also Trading Techs. Int'l, Inc. v. eSpeed, Inc., 595 F.3d 1340, 1354 (Fed. Cir.
2010) (finding that a “wherein clause” expressly excluded some potential embodiments of the
claim). The fact that “the relaxed position” in claim 1 is defined as a “sitting position” does not
foreclose the possibility that other “relaxed positions” exist and are indeed described in the
specification.
The patent prosecution history further supports iWalk’s position that “the relaxed
position,” as it is used in claim 1, refers specifically to a “sitting position.” When originally
filed, claim 1 of the ’927 patent recited “processing . . . to determine whether the user is in a
relaxed position” and “adjusting . . . based on whether the user is in a relaxed position.” The
PTO concluded that the unmodified phrase “a relaxed position” covered a variety of positions,
including standing, and therefore found it obvious in light of the prior art. The PTO then advised
that dependent claim 27, which recited “[t]he method of claim [1], wherein the relaxed position
is a sitting position,” would be allowable if “rewritten in independent form.” The inventors
responded by amending claim 1 to incorporate claim 27 by adding the phrase “wherein the
relaxed position is a sitting position” and changing “a relaxed position” to “the relaxed position”
in the preceding clause. The Federal Circuit has found such use of “wherein” clauses in
amendments to be instructive in claim construction. See, e.g., Fantasy Sports Props., Inc. v.
Sportsline.com, Inc., 287 F.3d 1108, 1111–16 (Fed. Cir. 2002) (finding that “wherein” clause
added to overcome prior art limited the construction of the term “bonus points” so as to exclude

41

the kind of “bonus points” described in the prior art). The Court will give the “wherein” clause
of claim 1 similar import.
Accordingly, the Court will construe the term “the relaxed position” to mean “a sitting
position.”6
J.

“Configurable Element”

The term “configurable element” appears in claim 1 and dependent claim 11 of the ’927
patent. The term’s use in claim 1 encompasses the more specific references in the later claims:
. . . adjusting the prosthetic ankle device based on whether the user is in the relaxed
position, wherein adjusting the prosthetic ankle device comprises automatically adjusting
a configurable element of the prosthetic ankle device.
’927 Patent at col. 40 ll. 1-5 (emphasis added).
1.

Indefiniteness

Rather than propose a construction for the term “configurable element,” iWalk contends
that the term is indefinite, and it therefore renders claims 1 and 11 of the ’927 patent invalid.
Again, in order to be valid, a patent claim must be sufficiently definite that “one skilled in the art
would understand the bounds of the claim when read in light of the specification.” Exxon
Research, 265 F.3d at 1375. Indefiniteness must be proved by clear and convincing evidence.
Halliburton, 514 F.3d at 1249.
iWalk contends that the term “configurable element” is indefinite because it cannot be
construed in such a way that it encompasses all of the “configurable elements” disclosed in the
claims of the ’927 patent and still conforms with the use of the included term “element” in the
6

The Court expressly does not construe the term “a relaxed position” to refer only to sitting. The Court
agrees with Össur that a number of “relaxed positions” are disclosed in the specification of the ’927 patent—such as
reclining, lying down, and leaning—but finds that the definite article preceding “relaxed position” as it is used in
claim 1 and dependent claim 7 indicates that the term refers to a specific “relaxed position,” namely sitting.

42

patent specification. Claims 9 and 11 of the ’927 patent disclose specific examples of
“configurable elements”—“the angle between the prosthetic foot and the limb member” and
“the amount of operating power.” ’927 Patent at col. 40 ll. 64-65, col. 42 ll. 6-7. Because claim
terms are normally used consistently throughout the patent, any construction of “configurable
element” must encompass both of these uses of the term. Phillips, 415 F.3d at 1314; Acromed.,
253 F.3d at 1382. iWalk concedes that Össur’s proposed construction—“parameter”—would do
so, but nonetheless takes issue with it because that construction is allegedly inconsistent with the
ordinary meaning of “element” and its use in the ’927 patent specification.
As support for its construction, iWalk cites to the American Heritage College Dictionary,
which defines “element” as, among other things, “a fundamental, essential, or irreducible
constituent of a composite entity.” iWalk then cites to examples of “elements” of the device that
are numbered in the drawings and described in the text of the ’927 patent specification,
suggesting that they conform to this definition. Those examples include: “the prosthetic ankle
joint,” “the sensor module,” and “the power module.” ’927 Patent at col. 6 ll. 1, col. 34 ll. 20,
co. 36 ll. 63.7 iWalk contends that there is no reasonable construction of the term “configurable
element” that encompasses these physical components of the device and the settings described in
claims 9 and 11.
iWalk’s argument is flawed for multiple reasons. First, and most importantly, iWalk has
set up a false requirement. Although it is well-established that a claim term must be interpreted
consistently throughout a patent, the specific term at issue—“configurable element”— is found

7

iWalk also contends that the specification describes the “heel” of the device as an element. However, the
specification actually describes “heel height,” which, not coincidentally, conforms with Össur’s proposed
“parameter” construction.

43

nowhere in the passages of the specification on which iWalk rests its indefiniteness contention.
Indeed, the included, but different, term “element” is found only in the part of the specification
that describes the numbering of the drawings; no specific examples are listed and it is not
expressly defined. The Court is therefore not required to construe “configurable element” such
that it has the same meaning as “element,” or even that it covers all of the purported examples of
“elements” in the specification. Second, even if such a requirement existed, the fact that Össur’s
proposed construction may not encompass all the examples of “elements,” even if proved, is not
clear and convincing evidence that no construction of the term whatsoever could encompass
them. Third, iWalk’s argument relies heavily on the incompatibility of Össur’s proposed
definition of “configurable element” with the dictionary definition of “element.” Again, the
Federal Circuit has strongly cautioned against the approach of importing limitations from
dictionary definitions into claim construction. Phillips, 415 F.3d at 1321.
Finally, attorney argument, without more, is generally not considered clear and
convincing evidence sufficient to overcome the presumption of validity. See, e.g., WesternGeco
LLC, 876 F. Supp. 2d at 875; Cacace, 812 F. Supp. 2d at 559-60. Here, it was not iWalk—the
party with the burden of proof as to indefiniteness—but Össur that put forth expert testimony on
the meaning of this term. Dr. Gard offered the opinion that “a person of ordinary skill in the art,
having read the ‘927 patent, including its specification and claims, would have readily
understood what the term ‘configurable element’ means and would not have found that term
ambiguous.” (Gard Dec. at ¶ 41). iWalk offered no competing expert testimony as evidence of
indefiniteness. Instead, they relied on the arguments recited above and on their crossexamination of Dr. Gard.

44

iWalk has not met its burden of proving the term “configurable element” to be indefinite.
Indeed, the record evidence suggests that a person of ordinary skill in the art would, in fact, be
able to understand the term. Accordingly, the Court finds that the term “configurable element”
is not indefinite.
2.

Claim Construction

As noted, Össur proposes to define the term “configurable element” as “parameter.”
iWalk concedes that this definition would fairly encompass the use of the term in claims 9 and
11 of the’927 patent, which disclose examples of “configurable elements.” Furthermore,
Össur’s expert, Dr. Gard, testified that construing “configurable element” to mean “parameter”
would be “perfectly reasonable and understandable to a person of ordinary skill in the art.” (Gard
Dec. at ¶ 41). Therefore, there is no reason why Össur’s proposed construction should not be
adopted; it adequately defines the term based on its usage in the claims themselves and conforms
with the understanding of those skilled in the art.
Accordingly, the Court will construe the term “configurable element” to mean
“parameter.”
K.

“Automatically Adjusting”

The term “automatically adjusting” appears in claim 1 of the ’927 patent. The relevant
part of the claim reads as follows:
. . . adjusting the prosthetic ankle device based on whether the user is in the relaxed
position, wherein adjusting the prosthetic ankle device comprises automatically
adjusting a configurable element of the prosthetic ankle device.
’927 Patent at col. 40 ll. 1-5 (emphasis added).
The parties appear to agree that the included term “adjusting” can be readily understood

45

according to its ordinary meaning and need not be given special construction. Össur, however,
contends that the term “automatically adjusting” refers to a very specific type of adjusting,
involving a change “from one state to another, based on the processed data.” iWalk contends
that the included term “automatically” should also simply be given its ordinary meaning, and
therefore, the whole term need not be construed.
As noted, the Court is not required to provide additional language construing a claim if
its ordinary meaning can be readily understood by a layperson and adopting it would resolve the
parties’ dispute concerning interpretation. See O2 Micro, 521 F.3d at 1361.
Here, adopting the ordinary meaning of the term “automatically adjusting” would settle
the interpretation dispute, because Össur’s proposed construction attempts to limit the term’s
scope to a subset of automatic adjustments—namely, changes in device states. As support for its
limiting construction of “automatically adjusting” Össur cites the specification of the ’927 patent
where it describes “a controller configured to automatically adjust the state of the prosthetic
ankle joint,” as well as other instances of automatic adjustments to various states, including
“RELAX” and “EXIT.” See ’927 Patent at col. 5 ll. 67 - col. 6:4, col. 13 ll. 59-60, col. 36 ll. 6062, col. 36 l. 66. Again, however, a court must not “import[] limitations from the specification
into the claim.” Phillips, 415 F.3d at 1323. The portions of the specification cited by Össur all
describe what is to be “automatically adjusted” in different scenarios. None of them indicate that
the term “automatically adjusting” somehow incorporates all of the descriptions in the
specification about specific automatic adjustments to the states of various components. See
Lucky Litter LLC v. ITC, 403 Fed. Appx. 490, 494 (Fed. Cir. 2010) (holding that “the words of a
claim are generally given their ordinary and customary meaning, absent a clear indication

46

otherwise from the specification or prosecution history, as where the patentee acts as his own
lexicographer or clearly disavows claim scope”). Without some evidence from the claim itself
that the term is so limited, the Court will not adopt a narrowing construction of an otherwise
easily understood claim term.
Össur further contends that in drafting the patent, it assigned a special meaning to the
term “automatically adjusting” that is evidenced by the cited portions of the specification. Claim
1 itself, particularly as construed herein, provides no support for this position. The claim
generally describes “automatically adjusting a configurable element.” Construing the term
“configurable element” to mean “parameter,” claim 1 of the ’927 patent indicates that an
adjustment is made to a parameter automatically. However, it is unclear how the “state” of a
parameter could be adjusted, which is what Össur’s proposed construction of the term would
require. Accordingly, the Court finds that Össur’s proposed construction lacks support in the
claim language, and therefore will not adopt it.
As support for its contention that term “automatically adjusting” need not be formally
construed, iWalk refers to the ordinary meaning of the term “automatically” and cites to the
specification of the ‘927 patent. The specification describes an embodiment wherein “the
prosthesis may automatically adjust the heel height without the need for user input.” ’927 Patent
at col. 13 ll. 59-60. iWalk contends that the ordinary meaning of “automatic” is “without user
input,” citing Personalized User Model LLP v. Google Inc., 2012 WL 295048, *29 (D. Del. Jan.
25, 2012), wherein the Court construed the term, as the parties had agreed, to mean “without
human intervention.” That understanding is consistent with two of the standard dictionary
definitions of “automatic”—“done or produced as if by machine” and “having a self-acting or

47

self-regulating mechanism.” Giving the term “automatically adjusting” its ordinary meaning,
then, conforms to the specification, which describes adjustments being made “without the need
for user input.” Furthermore, there is no evidence that those skilled in the art would understand
the term differently from its ordinary use in the specification. See Phillips, 415 F.3d at 13151317.
Accordingly, the Court will not construe the term “automatically adjusting” beyond
attributing to it its ordinary meaning.
IV.

Conclusion
For the foregoing reasons, the disputed claim terms are construed as follows:
1.

the terms “substantially mimic[s] the movement of a healthy ankle,” “position,”
“movement,” and “automatically adjusting” have their ordinary meaning and need
not be given special construction by the Court;

2.

the term “gait pattern(s) or event(s)” means “detectable series of normal ankle
movements during locomotion or normal ankle functions during nonlocomotion”;

3.

the term “ankle-angle adjustments” means “a change, or multiple changes, to the
angle between the foot unit and the lower limb member”;

4.

the term “processing module” means a “computer-like component, or CPU, of the
ankle device”;

5.

the term “subsequent gait cycles” means “later gait cycles”;

6.

the term “corresponding to [a/the] determined gait pattern or event” means
“corresponding to [a/the] gait pattern or event determination made with the data”;

7.

the term “state transition is detected from the determined gait pattern or event to a

48

different gait pattern or event” means “change is detected from the determined
gait pattern or event to a different gait pattern or event”;
8.

the term “the relaxed position” means “a sitting position”; and

9.

the term “configurable element” means “parameter.”

So Ordered.

/s/ F. Dennis Saylor
F. Dennis Saylor IV
United States District Judge
Dated: August 8, 2013

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