United States District Court, N.D. Illinois
April 22, 2004.
CFM CORPORATION, Plaintiff/Counter-Defendant,
DIMPLEX NORTH AMERICA LTD., Defendant/Counter-Plaintiff
The opinion of the court was delivered by: HARRY LEINENWEBER, District Judge
MEMORANDUM OPINION AND ORDER
PERTAINING TO CLAIMS CONSTRUCTION
Plaintiff CFM Corporation (hereinafter, "CFM") brings this action
against Defendant Dimplex North America Ltd. (hereinafter, "Dimplex")
seeking a declaratory judgment that Dimplex's U.S. Patent No, 5, 642, 580
(the "`580 Patent") is invalid and unenforceable. CFM also seeks a
declaration that it is not infringing on Dimplex's `580 Patent. Dimplex
counterclaims that CFM is infringing on the `580 Patent. Presently before
the Court are the parties' Markman briefs for claims construction as to
the meaning and scope of several disputed claims of the `580 Patent.
The `580 patent pertains to an electric fireplace "having an improved
flame simulating apparatus." `The specification and claims provide for a
light source, a flame effect element, a flicker element, a fuel bed, and
a partially reflecting screen that displays an image of the fuel bed,
simulated flames, and simulated gasses. In the preferred embodiment, the flame effect element is
illustrated and described as "a single thin sheet of a lightweight,
substantially opaque" material that contains "a plurality of slits" to
permit light to pass through" as the material "billows under the influence
of air currents" from an air blower. The flicker element is described as
an elongated rod "having a plurality of reflective strips extending
radially outwardly" that reflect light so as to simulate the upward
movement of gasses and flames.
II. LEGAL STANDARDS
A. Claims Construction
Claim construction is a matter of law reserved for the Court. See
Markman v. Westview Instruments, Inc., 517 U.S. 370 (1996). "[O]nly those
terms need be construed that are in controversy, and only to the extent
necessary to resolve the controversy." Vivid Techs., Inc. v. American
Sci. & Eng'g, Inc., 200 F.3d 795, 804 (Fed. Cir. 1999). Claims are
"construed without regard to the accused product," Jurgens v. McKasy,
927 F.2d 1552, 1560 (Fed. Cir. 1991), and are interpreted through the
lens of a "person of ordinary skill in the field of the invention,"
Multiform Dessicants, Inc. v. Medzam, Ltd., 133 F.3d 1473, 1477 (Fed.
Cir. 1998) To ascertain the meaning of a patent claim, the Court looks
first to intrinsic evidence, which consists of the language of the
claim, the specification, and, if in evidence, the prosecution history. Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed.
Cir. 1996). "[W]ords in a claim are generally given their ordinary and
customary meaning." Id. However, "a patentee may choose to be his own
lexicographer and use terms in a manner other than their ordinary
meaning, as long as the special definition of the term is clearly stated
in the patent specification or file history." Id. Thus, because "[t]he
specification acts as a dictionary when it expressly defines terms used in
the claims or when it defines terms by implication," it "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. If in
evidence, the prosecution history, which consists of "the complete record
of all the proceedings before the Patent and Trademark Office, including
any express representations made by the applicant regarding the scope of
the claims," id., must also be examined. "The prosecution history limits
the interpretation of claim terms so as to exclude any interpretation
that was disclaimed during prosecution." Southwall Tech., Inc. v.
Cardinal IG Co., 54 F.3d 1570, 1576 (Fed. Cir. 1995); cf. Ekchian v. Home
Depot, Inc., 104 F.3d 1299, 1304 (Fed. Cir. 1997).
The guidance offered by intrinsic evidence is usually sufficient to
determine conclusively the meaning and scope of the claim at issue.
Vitronics, 90 F.3d at 1583. Accordingly, resort to extrinsic evidence is
only appropriate where there is "still some genuine ambiguity in the claims, after consideration of all
available intrinsic evidence." Id. at 1584. "Extrinsic evidence consists
of all evidence external to the patent and prosecution history, including
expert and inventor testimony, dictionaries and learned treatises."
Markman v, Westview Instruments, Inc., 52 F.3d 967 (Fed. Cir. 1995). A
court is always free to consult extrinsic evidence, however, if it will
assist the court's understanding of the technology underlying the
patent. Pitney Bowes, Inc. v. Hewlett-Packard Co., 182 F.3d.1298, 1309
(Fed. Cir. 1999).
As a preliminary matter, the parties' opening Markman briefs include
discussion of certain phrases from claims that parties anticipated may be
challenged by their opponent. As it turns out, some of the claim phrases
raised in the opening briefs were not contested in the responsive
Markman briefs, and thus the Court will address only those phrases
included in the proposed claim construction charts in the parties'
responsive Markman briefs.
Claim 1: "A flame effect having means for
transmitting light from said light
source to produce a moving flame effect"
The parties (and the Court) agree that this portion of Claim 1 is
written in a means-plus-function format, and, correspondingly, must be
interpreted under 35 U.S.C. § 112 par 6, and the corresponding case law.
See, Cardiac Pacemakers v. St. Jude Medical, 296 F.3d 1106
2002). Construction of a means-plus-function limitation involves two steps. See id. at 1113. First, the Court must
determine the claimed function, but must include only those limitations
contained in the claim language, rather than the specification. See id.
The Court utilizes ordinary claim construction principles to interpret
the limitation language. See id. Second, after identifying the function,
the Court must determine what structure, if any, disclosed in the
specification corresponds to the claimed function. See id.
CFM contends that the claimed function here is "transmitting light
through a moving flame effect element." Specifically, CFM argues that
this function includes "both (1) permitting a passage of light through
the flame effect and (2) permitting movement of the flame effect
element." (CFM depends heavily on the purported prior art of the
Butterfield 4,965,707 patent in its interpretation of the claimed
function here; however, as shown below, the instrinsic evidence found
within the `580 patent is sufficient to determine the function and the
Court need not turn to the `707 patent.) CFM next contends that the
corresponding structure to effect this function is a single sheet of
light-weight, substantially opaque, material than can "ripple, billow, or
otherwise move." Thus, according to CFM, the proper construction for this
portion of Claim 1 should read:
A device used in simulating flames that is made of
flexible opaque material and is movable, with
light transmitting areas such that light passing
therethrough is seen to change in response to movement of opaque material.
Dimplex, of course, takes issue with CFM's proposed construction. The
crux of the parties' disagreement appears to center on whether the
means-plus-function limitation in Claim 1 requires that the flame effect
element be a moving structure. CFM relies heavily on the clause "to
produce a moving flame effect" to show that the function necessarily
includes production of a moving flame effect, which in turn requires the
movement of the corresponding structure, the flame effect element.
Dimplex responds by claiming that CFM erroneously premises its
construction on the flame effect element as being the means for
transmitting light, rather than simply "having means for transmitting
light," as the claim plainly reads. Dimplex contends that the "means for
transmitting light are openings, holes, gaps or slits" (or other
equivalents thereof) in the flame effect element that permit passage of
light through the flame effect element. Dimplex next argues that CFM
mischaracterizes the claimed function, which is the transmission of light
rather than the creation of a moving flame effect. (Dimplex also raises
the issue of claim differentiation to show that Claim 1 does not
necessarily impart motion on the flame effect element; the Court,
however, does not need to address this issue of claim differentiation to
interpret the applicable language in Claim 1.) Ultimately, Dimplex has the stronger argument here. In the normal
course of interpretation of a means-plus-function clause, the phrase
"means for" is a signal for the clause that recites the function. See
Lockheed Martin Corp. v. Space System/Loral, Inc., 324 F.3d 1308
(Fed. Cir. 2003). Thus, a court should look to the "means for" phrase to
determine the function. See id. Clauses that follow the "means for"
clause that contain nothing more than a recitation of the ultimate
desired result of the function should not be considered part of the
function. See id. Here, the "means for" clause indicates that the claimed
function is "transmitting light from said light source." The subsequent
clause "to produce a moving flame effect" merely states the ultimate
desired result of the limitation in the claim (i.e., "a moving flame
effect") and therefore "adds nothing to the substance of the claim."
Texas Instruments Inc. v. United States Int'l Trade Comm'n, 988 F.2d 1165
1172 (Fed. Cir. 1993). Accordingly, the function at issue here should not
contain the production of a moving flame effect, as this is an ultimate
result of a series of operations in the device, and is not the proper
subject of the more-immediate function of transmitting light that is
specified in Claim 1. (In any event, even if the function were to include
the phrase "to produce a moving flame effect," the intrinsic evidence
here indicates that a moving flame effect element is not the only
mechanism for producing a moving flame effect, but rather the flicker
element also "facilitates the appearance of upwardly moving gasses and
colored flames." Col. 5, 11. 34-35 (emphasis added).) Although the specification
must not limit the claim, it can inform or confirm construction of a
claim in controversy. See, e.g., Texas Digital Systems, Inc. v.
Telegenix, 308 F.3d 1193
, 1204-05 (Fed. Cir. 2002).
Turning now to the corresponding structure necessary for carrying out
the function of "transmitting light from said light source," it is clear
that the flame effect element is linked in the specification with this
function. CFM argues strongly that the specification necessarily
indicates that the flame effect element structure must have a moving
component to produce the moving flame effect. However, as noted above,
the function here is merely the transmission of light, and not the
production of the moving flame effect. Moreover, neither the plain
language of the limitation nor the specification indicate that the flame
effect element necessarily must move to create the moving flame effect.
Indeed, the specifications show that the flicker element is related not
only to the appearance of upwardly moving gasses but also the movement of
colored flames. See Col 5, 11. 19-20, 32-44.
The parties also submitted additional briefing on the issue of whether
the subsequent prosecution history of a subsequent related patent (Patent
No. 6,047,489) informs the claim construction of the phrase at issue
here. Assuming arguendo that such subsequent prosecution history
is pertinent extrinsic evidence worthy of consideration, the Court does
not find that it adds sufficient clarification to the intrinsic evidence here to alter the Court's
claim construction. Specifically, both parties point to conflicting
language in the prosecution history of the subsequent patent that
purportedly supports their interpretation of language at issue in Claim 1
of the `580 patent. Because the intrinsic evidence of the `580 patent is
sufficient to construe the phrase at issue here, and because of the
conflicting nature of the additional proffered extrinsic evidence, the
Court finds that consideration of the `489 patent does not add additional
Taken together, the Court finds the following claim construction for
the phrase "A flame effect having means for transmitting light from said
light source to produce a moving flame effect":
A stationary or mobile component made of light-weight
material that contains openings for transmitting light
to produce an impression of moving flames.
Claims 1 and 30: "flicker element having at least one
CFM contends that this portion of Claims 1 and 30 fails to describe
what the flicker element is structurally. CFM argues that the claims
require only that the flicker element have one reflective surface.
Dimplex, in turn, argues that the plain and ordinary meaning of "flicker"
is "a quick wavering motion." According to Dimplex, "having at least one
reflective surface" requires that the flicker element have at least one
surface that bends or throws back light. Dimplex points to the
specification to show that flicker element imparts motion on the reflected light from the
The principal disagreement between the parties here centers on how to
treat the word "flicker" in relationship to the other claim language. The
general rule, of course, is that the Court should first look to plain and
ordinary meaning of "flicker" from the vantage point of one skilled in
the art. Here, neither party argues that the ordinary dictionary
definition of "flicker" differs from the one employed by those skilled in
the art. The parties essentially agree that the noun and verb form of
"flicker" connotes wavering of light. Next, the Court may look to the
intrinsic evidence (typically the specification) to ascertain consistency
between the ordinary meaning of "flicker" and its use by the patentee.
See Texas Digital Systems, Inc., 308 F.3d at 1204-05. Here, the ordinary
and plain meaning of "flicker" whether in noun or verb form
unmistakably imparts wavering light, and this is entirely consistent with
and supported by the specification's description of the flicker
element. It is therefore appropriate to include this definition of
"flicker" into the claim construction as follows:
a component part having at least one surface that
reflects light in a wavering motion.
Claim 1: "a screen having a partially
reflecting surface and a diffusing surface"
CFM depends heavily on the prior art `707 patent to support its claim
interpretation here. CFM argues that the `707 patent's description of the screen at issue there dictates that the claim
language here should be construed, in part, as a "panel with two surfaces
. . . that acts as a mirror." CFM also points to the specification
language indicating that the screen is "positioned immediately behind the
fuel bed 26 so that the fuel bed 26 will be reflected in the reflecting
surface 44 to give the illusion of depth" to support its view that the
"entire point of this mirrored surface is to provide the clear image of
simulated flames from between the fuel bed and its reflection on the
screen." Dimplex, in turn, contends that the phrase at issue is not
ambiguous. Relying on dictionary definitions, Dimplex notes that a
"partially reflecting surface" is a surface that "partially bends light."
A "diffusing surface" is a surface that "disperses and softens light."
The plain terms in this claim are relatively straightforward and must
be afforded their everyday meaning. CFM's argument not only seeks to
introduce improperly the specifications from another patent but also
attempts to limit the claim to the specification terms. The proper claim
a screen having a surface that partially bends
light or gives back an image and also having a
surface that disperses and softens light.
Claims 1 and 30: "an Image . . . which
resembles moving flames" and "an image
which resembles moving gasses"
CFM contends that the reference in Claim 1 to an "image of moving
flames" addresses an image that is necessarily different from simulation of "moving gasses from a fire" specified in Claim
30. CFM bases its proposed construction on the argument that the image of
moving flames is "something defined by vertically oriented slits cut into
the moving flame effect element," whereas the simulation of upwardly
moving gasses is created by use of the flicker element. Dimplex finds
little ambiguity in this claim language and simply proposes that it be
construed precisely as the language states.
It is difficult to see where controversy lies in the construction of
these claims. Dimplex appears to concede that the images are indeed
distinct. The point of difference between the parties appears to be CFM's
contention that the image of moving gasses must appear above the image of
moving flames. However, nothing in the claim itself specifies this and
there is no other controlling intrinsic evidence that compels this
result. Accordingly, the Court adopts the following construction for Man
image . . . which resembles moving flames," and "an image which resembles
moving gasses from a fire," respectively:
a representation that gives the appearance of
a representation that gives the appearance of
moving gasses from a fire.
Claims 1 and 30: "the image of moving flames
[or moving gasses] appears to emanate between
the simulated fuel bed and its image on the screen"
CFM notes that "this claim terminology is straightforward and may not
actually be in any serious controversy." Indeed, there is no controversy as to the actual terms, but rather CFM expresses concern
that Dimplex may argue that such images "can be met when the unit is
turned off." Dimplex does not make this argument. Thus, there is no
controversy in the construction of this claim and therefore the Court
need not create any.
For the reasons stated here, the above claim construction is hereby
IT IS SO ORDERED.
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