United States Court of Appeals for the Federal Circuit
2006-1406, -1435
HONEYWELL INTERNATIONAL, INC.
and HONEYWELL INTELLECTUAL PROPERTIES, INC.,
Plaintiffs-Cross Appellants,
v.
UNIVERSAL AVIONICS SYSTEMS CORP.,
Defendant-Appellant,
and
SANDEL AVIONICS, INC.,
Defendant.
Richard G. Taranto, Farr & Taranto, of Washington, DC, argued for the plaintiffs-
cross appellants. With him on the brief were Steven D. McCormick and Atif N. Khawaja,
Kirkland & Ellis LLP, of Chicago, Illinois.
Howard G. Pollack, Fish & Richardson P.C., of Redwood City, California, argued
for defendant-appellant. With him on the briefs were Michael R. Headley, John V.
Picone, III, and John A. Dragseth, Fish & Richardson P.C., P.A., of Minneapolis,
Minnesota. Of counsel were Scott J. Bornstein and Allan A. Kassenoff, Greenberg
Traurig LLP, of New York, New York.
Appealed from: United States District Court for the District of Delaware
Magistrate Judge Mary Patricia Thynge
United States Court of Appeals for the Federal Circuit
2006-1406,-1435
HONEYWELL INTERNATIONAL, INC.
and HONEYWELL INTELLECTUAL PROPERTIES, INC.,
Plaintiffs-Cross Appellants,
v.
UNIVERSAL AVIONICS SYSTEMS CORP.,
Defendant-Appellant,
and
SANDEL AVIONICS, INC.,
Defendant.
__________________________
DECIDED: July 3, 2007
___________________________
Before BRYSON, Circuit Judge, PLAGER, Senior Circuit Judge, and GAJARSA, Circuit
Judge.
Opinion for the court filed by Circuit Judge BRYSON. Dissenting opinion filed by Senior
Circuit Judge PLAGER.
BRYSON, Circuit Judge.
This case concerns a patent on aircraft technology that plaintiffs Honeywell
International, Inc., and Honeywell Intellectual Properties, Inc., (collectively, “Honeywell”)
asserted against defendant Universal Avionics Systems Corp. We hold that the district
court correctly interpreted the disputed terms of the patent and that, under the correct
interpretation, the jury permissibly found that Universal infringed Honeywell’s patent.
I
The patent in suit, U.S. Patent No. 4,914,436 (“the ’436 patent”), concerns a
system for warning airplane pilots of potentially hazardous flight conditions. The criteria
for issuing such warnings vary for different phases of a flight; the patent deals with
warnings when an aircraft is on its final approach to an airport runway. Specifically, the
patent claims a system for detecting whether an aircraft is on final approach to a runway
and enabling a ground proximity warning system during final approach. According to
the patent, older airplanes use a distinctive wing flap position when landing. As a result,
the final approach warning systems on such airplanes can be enabled based on the
position of the wing flaps. Newer airplanes, however, do not use a distinctive wing flap
position when landing. In those airplanes, wing flap position is therefore not a reliable
indicator of when to enable a warning system for the final approach phase of flight.
The patentees’ system detects whether the aircraft is on final approach to an
airport without relying on wing flap position. Instead, their detection system stores the
latitude and longitude coordinates of various airport runways, as well as the distance
from each runway at which an aircraft is deemed to be on final approach. The patent
calls the area defined by the distance from the runway the “enabling envelope,” and it
refers to the aircraft’s entry into the envelope as enabling the warning system. During
flight, the detection system locates the runway closest to the aircraft’s current position
and determines whether the aircraft is within the enabling envelope for that runway.
2006-1406,-1435 2
In addition to storing coordinates for each runway, the patented system can also
store the direction that each runway points. That information allows the system to
determine not only whether an airplane is close to a runway, but also whether the
airplane is aligned with the runway. With that capacity, the detection system can
expand the radius of the enabling envelope if the aircraft is aligned with the runway and
shrink the radius if the aircraft is not aligned with the runway, a feature that improves the
capacity of the system to detect whether the aircraft is on final approach to the airport.
Honeywell filed suit alleging that Universal infringed the first claim of its patent by
making and selling a device known as the Terrain Awareness and Warning System
(“TAWS”). The parties disputed the proper construction of several terms of that claim,
as well as whether Universal was entitled to summary judgment of noninfringement.
The district court (per a magistrate judge) adopted Honeywell’s claim constructions and
denied Universal’s motion for summary judgment of noninfringement. The case then
proceeded to trial, and a jury found that Universal’s accused product infringed the
asserted claim. The district court entered judgment accordingly and awarded damages
to Honeywell. Universal appeals.
II
Universal first argues that the district court erred in construing the term “heading
of the aircraft” and that, under the proper construction, Universal is entitled as a matter
of law to judgment of noninfringement. The term “heading of the aircraft” appears in the
fourth and fifth limitations of the asserted claim, which reads in full as follows:
1. A system for use in an aircraft for providing an enabling envelope for a
ground proximity warning system for an aircraft comprising:
2006-1406,-1435 3
[1] a first source of signals representative of the longitude and latitude of
an airport;
[2] a second source of signals representative of the current longitude and
latitude of said aircraft;
[3] means responsive to said first source of signals representative of the
longitude and latitude of said airport and said second source of signals
representative of the current longitude and latitude of said aircraft for
[a] computing the distance of said aircraft from said airport and
[b] providing an enabling envelope for enabling the warning system
as a function of said distance of the aircraft with respect to said
airport;
[4] a source of signals representative of the relative angular position of a
particular runway with respect to the heading of the aircraft; and
[5] means responsive to said first and second sources of signals for
providing a signal representative of the alignment of the aircraft with the
runway by determining the angle between the runway and the heading of
the aircraft.
’436 patent, col. 7, ll. 40–63. The district court concluded that the patentees used the
term “heading of the aircraft” to refer to what would normally be referred to as the
aircraft’s “bearing,” i.e., the direction to the aircraft from a runway. We agree.
The conventional meaning of the terms “heading” and “bearing” is undisputed.
“Heading” ordinarily refers to the direction in which an object is pointing. “Bearing”
ordinarily refers to the direction from an observer to an object. The specification and
prosecution history make clear, however, that the patentees used the term “heading” in
a manner different from its ordinary meaning. When a patentee defines a claim term,
the patentee’s definition governs, even if it is contrary to the conventional meaning of
the term. Phillips v. AWH Corp., 415 F.3d 1303, 1321 (Fed. Cir. 2005) (en banc) (“[T]he
specification is the single best guide to the meaning of a disputed term, and . . . the
specification acts as a dictionary when it expressly defines terms used in the claims or
when it defines terms by implication.” (quotation marks omitted)); Bell Atl. Network
2006-1406,-1435 4
Servs., Inc. v. Covad Commc’ns Group, Inc., 262 F.3d 1258, 1268 (Fed. Cir. 2001)
(stating that “a patentee may choose to be his own lexicographer and use terms in a
manner other than their ordinary meaning”). A claim term may be defined in a particular
manner for purposes of a patent even “without an explicit statement of redefinition.” Bell
Atl., 262 F.3d at 1268.
The specification of the ’436 patent clearly communicates the meaning the
patentees have assigned to the term “heading.” It does so by describing the claimed
system’s alignment determination as depending on the direction of the aircraft from the
runway (i.e., what is conventionally known as the aircraft’s bearing), not the direction in
which the aircraft is pointing (i.e., what is conventionally known as the aircraft’s
heading). That alignment computation is depicted in figure 5 of the patent as follows:
’436 patent, fig. 5. The specification explains that signals X and Y are the differences in
longitude and latitude between the position of the aircraft and the centerpoint of the
nearest runway. By computing the arctangent of the ratio between Y and X, devices 46,
47, and 48 compute the angle of a line connecting the centerpoint of the runway to the
position of the aircraft. In other words, they compute the angle of a line having a
direction that is conventionally known as the bearing of the aircraft from the runway.
Device 50 then compares the direction of that line with the direction that the runway is
pointing, resulting in “a signal which is representative of the aircraft’s alignment with the
particular runway.” Id., col. 6, ll. 35–36. Thus, the specification makes it clear that in
2006-1406,-1435 5
referring to the “alignment” of an aircraft with a runway, the patent denotes the extent to
which the runway points at the aircraft, not the extent to which the aircraft points at the
runway or points in the same direction that the runway points.
The specification discloses no other form of alignment. If Universal’s
construction were adopted, the disclosed embodiment would not relate to any limitation
of the claimed invention, despite the clear link between the alignment computation
discussed in the specification and the alignment computation called for by the claims.
The specification refers to the calculation of the alignment of the aircraft with the runway
as an “important feature of the present invention.” ’436 patent, col. 6, ll. 6–7. That
characterization indicates that the disclosed alignment computation is the claimed
“alignment of the aircraft with the runway,” and shows that the patentees used the term
“heading of the aircraft” to refer to the line connecting a reference point on the runway to
the position of the aircraft. Because that is the construction that “most naturally aligns
with the patent’s description of the invention,” Renishaw PLC v. Marposs Societa’ per
Azioni, 158 F.3d 1243, 1250 (Fed. Cir. 1998), the district court properly held it to be the
correct one.
The prosecution history confirms that when the patentees wrote “heading,” they
meant “bearing.” Application claim 14, which became issued claim 1, initially phrased
two of its limitations as follows:
a source of signals representative of the relative angular position of a
particular runway with respect to a datum and
means . . . for providing a signal representative of the alignment of the
aircraft with the runway.
The “source of signals” is provided by a database of the angular directions of various
runways, and the reference “datum” is a direction, such as due north, against which the
2006-1406,-1435 6
runway angles are determined. The specification stated, as it does now, that the
alignment of an aircraft with a runway is determined by comparing the direction to the
aircraft from the runway with the direction of the runway.
The examiner rejected application claim 14 based on his confusion about “how a
runway is compared to a datum.” In response, the patentees replaced the phrase “a
datum” with “the heading of the aircraft,” and they added the language “by determining
the angle between the runway and the heading of the aircraft” to the last limitation. In
their remarks about the amendment, the patentees explained that the claimed alignment
determination requires comparing the direction of a runway against either a fixed
reference line, such as a latitude or longitude line, or against the “heading” of the aircraft
itself:
It should be clear that the angular position of a runway must
be referenced to either a datum, for example, a reference
latitude or longitude line, or to the heading of the aircraft in
order for the angular difference between the heading of the
aircraft and the heading of the runway to be computed to
determine the alignment of the aircraft with the particular
runway.
In that manner, the patentees explained that the angle used to determine alignment can
be identified without mentioning a “datum” by simply identifying the two lines that form
the angle: the line formed by the runway and the line from a point on the runway to the
position of the aircraft (a line that the patentees called the “heading of the aircraft”).
The examiner allowed application claim 14 as amended. At the same time, the
examiner rejected two pending claims that claimed an alignment determination based
on the position of the aircraft and the angle of the runway; those pending claims did not
recite that the alignment computation involved the position of the runway or the
“heading of the aircraft.” In response to the examiner’s rejection, the patentees added
2006-1406,-1435 7
to each claim a limitation reciting that the alignment determination uses the position of
the runway. They explained that the added limitation allowed the claimed invention to
“determine the heading of the aircraft with respect to the nearest airport” using the
trigonometric functions discussed in the specification (which, accurately labeled,
compute the bearing of an aircraft from a runway). The patentees expressly stated that
“the output of the arctan device [i.e., aircraft bearing] represents the heading of the
aircraft.”
Following a further rejection, the patentees added to those claims the same
“heading of the aircraft” language that was used in application claim 14. They explained
that they amended the pending claims “to conform their language to similar language
contained in claims 14 and 19,” thus harmonizing the relevant language of their pending
claims and their allowed claims. After that amendment, the examiner allowed the
pending claims without comment.
The specification and prosecution history both make clear that the patentees
used the term “heading” to refer to the angular direction of an object from a point on a
runway. Thus, the “heading of the aircraft” is the angular direction of the aircraft from a
point on a runway, and the “heading of the runway” is the angular direction of the
runway line from a point on that runway. To hold otherwise would not include within the
scope of the claim a preferred embodiment that the patentees labeled an “important
feature of the present invention” and would ignore the patentees’ definition of the term
“heading” and their consistent use of that term throughout the prosecution history. The
jury’s finding that Universal’s accused device detects alignment by computing the
2006-1406,-1435 8
“heading of the aircraft” within the meaning of the asserted claim is therefore based on a
proper interpretation of that limitation.
III
Universal next contends that the district court erred by construing the term
“enabling envelope” in the phrase “an enabling envelope for enabling the [ground
proximity] warning system” to mean “activating or turning on a set of limitations within
which an aircraft can perform safely and effectively.” Universal argues that the district
court’s construction improperly encompasses a system that uses distance as an
operative warning parameter; that is, the court’s construction allowed claim 1 of the ’436
patent to cover a system that uses the distance of an airplane from an airport not just as
a trigger to enable the warning system, but as one of the operative warning parameters
in the warning system itself. Universal characterizes the warning system of its accused
device as being “always on” and therefore not being “enabled” based on the distance of
the airplane from an airport. Universal contends that its system does not fall within the
scope of claim 1, as properly construed, because the claim should have been construed
to encompass only the use of “an enclosed boundary for activating or turning on a
warning system as a function of distance of the aircraft with respect to the airport and
wherein the warning system does not itself use that distance as an operative warning
parameter.”
The language of claim 1 is broad enough to cover any system that creates an
area within a particular distance from an airport in which a ground proximity warning
system will operate to give a warning when another parameter is triggered, such as the
aircraft’s height above the ground. Moreover, nothing in the specification requires that
2006-1406,-1435 9
the term “enabling envelope” be given a narrower construction. Universal notes that the
specification describes a system that uses some indicator other than flap position to
enable a warning system and that distance was not used as a parameter in the prior art
warning systems described in the specification. While that is true, the specification is
not at odds with the court’s construction of the term “enabling envelope,” which referred
to “activating or turning on” a set of limitations for safe operation of the aircraft.
Relying on a passage from the prosecution history, Universal contends that
during prosecution the applicants disclaimed a ground proximity warning system that
uses airport distance in determining whether to issue a ground proximity warning, as the
warning system of the accused device does. The purported disclaimer came in the
course of one of the applicants’ responses to the examiner’s rejection of several claims
as obvious in light of an article by Jeffrey Parnau about aircraft systems that warn pilots
that they are about to enter restricted airspace. The Parnau reference disclosed a
system that would give a warning based on an aircraft’s distance from a specific point.
The examiner found it obvious from that reference to make that point the center of an
airport runway and to use the aircraft’s distance from that point to determine when the
airplane is on final approach to the runway.
In response, the applicants distinguished their final-approach detection system
from the Parnau warning system as follows:
While the applicants agree with the Examiner’s characterization of the
Parnau reference, it is equally clear that the warning system referred to in
the Parnau reference relies on distance as an operative warning
parameter. . . . However, such a warning is based solely on the distance
of the aircraft from the restricted airspace. In contradistinction, the
warning system recited in the claims at issue recites a ‘warning of a
hazardous flight condition’ enabled ‘as a function of the distance between
the aircraft and a reference point.’ Thus, it should be clear that contrary to
2006-1406,-1435 10
the teachings of Parnau, the warning system recited in the claims at issue
does not utilize distance as an operative warning parameter, but merely to
enable the warning system.
Focusing on the applicants’ use of the indefinite article “an” in referring to the term
“operative warning parameter,” Universal argues that the applicants disclaimed any
system in which distance was used as one factor in determining whether to issue a
warning.
Honeywell argues that the passage in question distinguishes Parnau on the
ground that it issues a warning based “solely on the distance of the aircraft from the
restricted airspace.” Thus, according to Honeywell, the warning in Parnau is triggered
solely by distance, whereas in the applicants’ claims, distance both enables the warning
system and may be used, in conjunction with some additional factor or factors such as
aircraft altitude, to trigger a warning.
The passage in question can be read either way. The reference to Parnau’s
warning as based “solely on . . . distance” supports Honeywell’s interpretation of the
passage, while the reference to the application claims as “not utiliz[ing] distance as an
operative warning parameter” supports Universal’s interpretation. In context, however,
it is plausible to read the phrase “an operative warning parameter” as referring to the
sole parameter that triggers a warning, particularly in light of the fact that in Parnau itself
distance is the sole operative warning parameter. The quoted passage can thus be
understood to distinguish Parnau as a system in which distance is used not to enable
the system, but to trigger a warning; read that way, the passage would not exclude a
system in which distance is used to enable and also as a parameter in determining
whether a warning should issue. Because the passage is ambiguous, we conclude that
2006-1406,-1435 11
it does not constitute a sufficiently clear and deliberate statement to meet the high
standard for finding a disclaimer of claim scope. See, e.g., N. Am. Container, Inc. v.
Plastipak Packaging, Inc., 415 F.3d 1335, 1345–46 (Fed. Cir. 2005). We therefore
reject Universal’s argument that the trial court’s construction of the claim term “enabling
envelope” was impermissibly broad. 1
IV
Universal next contends that the trial court erred in construing the term “ground
proximity warning system” to be broader than the specific alerting systems approved by
the Federal Aviation Administration at the time of the patent application, i.e., the prior art
systems that were mandated for use at that time. Because the prior art systems did not
use distance from an airport to trigger alerts, Universal contends that the district court’s
construction should have excluded any monitoring system (such as the accused
system) that uses distance from an airport as a parameter to trigger a ground proximity
alert.
Contrary to Universal’s contention, the patent does not limit the phrase “ground
proximity warning system” to the particular system or systems approved at the time of
the application. The context makes it clear that the term is used generically, to describe
any system that warns of ground proximity, regardless of whether the system is
1
Universal also argues that the claim term “envelope” should be construed to
have its plain meaning of “a boundary that encloses.” Although the district court defined
“enabling envelope” for the jury as “activating or turning on a set of limitations within
which an aircraft can perform safely and effectively,” that construction more accurately
defines the claim term “enabling the warning system.” It is not clear that Universal
preserved an objection to that aspect of the jury instruction, but in any event because
nothing turns on the precise definition of “enabling envelope,” that minor semantic issue
is not a basis for overturning the verdict.
2006-1406,-1435 12
approved, manufactured, proposed, or otherwise. The specification refers generically to
systems “that provide warning or advisory indications in the event of hazardous flight
conditions,” including “systems generally known as ground proximity warning systems
for aircraft that serve to monitor the flight conditions of an aircraft and provide a warning
if flight conditions are such that an inadvertent contact with the ground is imminent.”
’436 patent, col. 1, ll. 15–22. The specification further provides that the invention “may
be used to enable other warning modes and even used in control systems,” id., col. 3, ll.
45–46, and “can be used in virtually any warning or control system where [a signal
indicating when an aircraft is on final or missed approach] is required,” id., col. 5, ll. 43–
45. The claims use similarly generic language to describe ground proximity warning
systems, such as “[a] warning system for use in an aircraft comprising: warning means
for providing a ground proximity warning according to predetermined criteria,” id., col. 7,
ll. 64–66, and “warning means for providing a ground proximity warning when an aircraft
encounters a hazardous flight condition,” id., col. 8, ll. 19–21. In light of the language
used in the specification and the absence of any contrary indication in the patent or the
prosecution history, the district court properly declined to limit the term “ground
proximity warning system” to any particular system, whether approved or designed to
use particular factors in warning of ground proximity.
V
Universal’s challenge to the verdict of infringement is based entirely on its claim
construction arguments. Because we have rejected those arguments, we reject
Universal’s noninfringement contention. The evidence at trial showed that Universal’s
system would not operate to give a warning if the aircraft were more than 15 miles from
2006-1406,-1435 13
an airport, and that within the 15 mile radius of the airport, it would give a warning if the
aircraft flew too low. Under these circumstances, and in light of the court’s claim
construction, the jury was justified in concluding that the Universal system had an
“enabling envelope” that was based on distance from the airport, that the enabling
envelope was “for enabling the [ground proximity] warning system,” and that the system
therefore infringed claim 1 of the ’436 patent.
AFFIRMED.
2006-1406,-1435 14
United States Court of Appeals for the Federal Circuit
2006-1406,-1435
HONEYWELL INTERNATIONAL, INC.
and HONEYWELL INTELLECTUAL PROPERTIES, INC.,
Plaintiffs-Cross Appellants,
v.
UNIVERSAL AVIONICS SYSTEMS CORP.,
Defendant-Appellant,
and
SANDEL AVIONICS, INC.,
Defendant.
PLAGER, Senior Circuit Judge, dissenting.
The patent in this case relates to the art of navigation, specifically the process for
determining the location at any given time of a craft (airplane or ship) proceeding
around the earth. This is a well-established art, in practice for centuries. In navigation,
the ordinary meaning of “heading” is the compass direction in which a craft is moving,
oriented to either magnetic or true north. A heading is understood to be quite different
from a “bearing,” which is the direction (expressed in compass terms) that one object
bears from another at any given moment. It is hardly likely that the people who invented
Honeywell’s patented navigation system were unaware of these conventions.
Claim terms are generally given their ordinary meaning as understood by a
person skilled in the art. Phillips v. AWH Corp., 415 F.3d 1303, 1312 (Fed. Cir. 2005)
(en banc). While a patentee may choose to be his own lexicographer and use a term in
a manner other than its ordinary meaning, and even though an “explicit statement of
redefinition” is not always necessary, nevertheless the patentee must clearly express an
intent to redefine the term. Bell Atl. Network Servs., Inc. v. Covad Commc’ns Group,
Inc., 262 F.3d 1258, 1268 (Fed. Cir. 2001).
In my view, the patent in this case falls far short of anything that suggests a clear
redefinition of the term “heading.” The term itself does not appear anywhere in the
patent’s written description. The majority relies on an embodiment described in the
patent that determines alignment as a function of the bearing of the aircraft from the
runway. But the alignment discussion in the written description does not use the term
heading to describe what is conventionally known as a bearing. Moreover, there is no
clear connection between that passage and the alignment determination set forth in
claim 1, which does use the term heading. This is not a case like Bell Atlantic in which
the patentee implicitly redefined a claim term by using it throughout the written
description in a manner consistent with an unconventional meaning. 262 F.3d at 1270-
73. Here the patentees did not use the term at all in the written description.
Furthermore, the prosecution history does not show a clear redefinition of the
term “heading.” While the applicants at times used the word “heading” to refer to what
is actually the bearing of the aircraft from the runway, they used the term in its
conventional sense when they referred to “the heading of the runway” in their
description of the invention. This inconsistent usage undercuts the argument that the
applicants intended to adopt a different definition for the term “heading.” Also, it is
apparent from the examiner’s citation of prior art references which use “heading” in the
2006-1406,-1435 2
conventional manner that he understood the term to have its ordinary meaning. The
applicants, cognizant of the examiner’s understanding of the term and almost certainly
aware of the distinction between a heading and a bearing, did not clearly signal the
necessary intent to depart from the ordinary meaning of “heading.”
At best, the patent and the prosecution history show that the inventors or their
representatives who drafted the claims and prosecuted the patent left considerable
confusion in the record about whether the claimed invention uses heading or bearing.
However, it is not the province of the courts to salvage poorly—or incorrectly—drafted
patent claims.
Fair notice to the public, and to competitors, of what is claimed depends on our
holding patentees to what they claim, not to what they might have claimed. It is the
responsibility of those who seek the benefits of the patent system to draft claims that
are clear and understandable. When courts fail to enforce that responsibility in a
meaningful way they inevitably contribute an additional element of indeterminacy to the
system. Sometimes being kind to a party results in being unkind to the larger interests
of the society. In my view this is such a case, and I respectfully dissent from the
decision.
2006-1406,-1435 3