Source: s3://data.kl3m.ai/documents/govinfo/USCOURTS/USCOURTS-cand-3_04-cv-01934/USCOURTS-cand-3_04-cv-01934-0/pdf.json

Nature of Suit Code: 830
Nature of Suit: Patent
Cause of Action: 35:145 Patent Infringement

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United States District Court

For the Northern District of California

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United States District Court

For the Northern District of California

IN THE UNITED STATES DISTRICT COURT

FOR THE NORTHERN DISTRICT OF CALIFORNIA

NELLCOR PURITAN BENNET, INC, et

al 

Plaintiffs,

v

PORTEX, INC, et al

Defendants. /

No C 04-1934 VRW

ORDER

On February 11, 2005, the court held a claim construction

hearing pursuant to Markman v Westview Instruments, Inc, 517 US 370

(1996). Based on the parties’ arguments at the hearing and their

submissions to the court, the court issues the following claim

construction order.

There are three patents-in-suit, all relating to

inventions in the field of endotracheal catheters (used, for

example, in resuscitation) and associated devices to determine

whether the catheter has been correctly inserted. For ease of

cross-reference to the parties’ submissions, the court discusses

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the patents and construes their terms in the same sequence as the

patents appear in the parties’ submissions. As the court writes

principally for the parties, it will not discuss the details of the

inventions or define terms well-known to those skilled in the art,

except as is necessary to construe the claims of the patents. 

I

United States Patent No 4,879,999 (the “‘999 patent”),

granted to Basil C Lehman et al on November 14, 1989, discloses “an

endotracheal device * * * with a colorimetric carbon dioxide

indicator.” ‘999 patent, Abstract. The device indicates “proper

intratracheal placement * * * by detecting * * * the presence of

carbon dioxide in expired air passing through the device.” Id. 

Plaintiffs assert that defendants infringe claims 3, 6-10, 13-17,

20-23, and 25 of the ‘999 patent. Doc #45 at 1.

United States Patent No 5,166,075 (the “‘075 patent”),

granted to Carl G Fehder on November 24, 1992, discloses a method

for “determining whether respiratory gas is present in a gaseous

sample.” ‘075 patent, Abstract. The method functions by bringing

the gaseous sample into contact with “an indicator which yields an

indication within a diagnostically effective period of time of the

presence * * * of carbon dioxide in concentration of at least 2%.” 

Id. Additionally, the indicator provides an indication of “the

presence of carbon dioxide in a sample of ambient air * * * delayed

beyond a predetermined period of time.” Id. Plaintiffs assert

that defendants infringe claims 1, 2, 4, 6-8, 15, 18-22, 24, and 25

of the ‘075 patent. Doc #45 at 1.

US Patent No 5,179,002 (the “‘002 patent”), granted

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January 12, 1993, also to Carl G Fehder, describes an apparatus

“for determining whether respiratory gas is present in a gaseous

sample.” ‘002 patent, Abstract. An indicator “yields an

indication within a diagnostically effective period of time of the

presence of * * * carbon dioxide in concentrations of at least 2%

while an indication of * * * carbon dioxide or other trace acidic

gas in * * * ambient air is delayed.” Id. Plaintiffs assert that

defendants infringe claims 1, 2, 4-9, 12, 22-24, and 25 of the ‘002

patent. Doc #45 at 1. 

II

The construction of patent claims is a question of law to

be determined by the court. Markman v Westview Instruments, Inc,

517 US 370 (1996). The goal of claim construction is “to interpret

what the patentee meant by a particular term or phrase in a claim.” 

Renishaw PLC v Marposs SpA, 158 F3d 1243, 1249 (Fed Cir 1998). In

determining what a patentee meant by a term or phrase, the court

looks first to the claim itself.

The claims of the patent provide the concise formal

definition of the invention. They are the numbered

paragraphs which “particularly [point] out and distinctly

[claim] the subject matter which the applicant regards as

his invention.” 35 USC § 112. It is to these wordings

that one must look to determine whether there has been

infringement. Courts can neither broaden nor narrow the

claims to give the patentee something different than what

he has set forth. No matter how great the temptations of

fairness or policy making, courts do not rework claims. 

They only interpret them.

EI Du Pont de Nemours & Co v Phillips Petroleum Co, 849 F2d 1430,

1433 (Fed Cir 1988). 

“The claims define the scope of the right to exclude; the

claim construction inquiry, therefore, begins and ends in all cases

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with the actual words of the claim.” Renishaw, 158 F3d at 1248. 

“The words used in the claim are viewed through the viewing glass

of a person skilled in the art.” Brookhill-Wilk 1, LLC v Intuitive

Surgical, Inc, 326 F3d 1215, 1220 (Fed Cir 2003) (citing Tegal Corp

v Tokyo Electron Am, Inc, 257 F3d 1331, 1342 (Fed Cir 2001)). 

“Absent a special and particular definition created by the patent

applicant, terms in a claim are to be given their ordinary and

accustomed meaning.” York Prods, Inc v Central Tractor Farm &

Family Ctr, 99 F3d 1568, 1572 (Fed Cir 1996). The court may, if

necessary, consult a variety of sources to determine the ordinary

and customary meaning of a claim term, including the claim terms

themselves, dictionaries, the written description, the drawings and

the prosecution history, if in evidence. Brookhill-Wilk 1, 326 F3d

at 1220. “Such intrinsic evidence is the most significant source

of legally operative meaning of disputed claim language.” 

Vitronics Corp v Conceptronic, Inc, 90 F3d 1576, 1582 (Fed Cir

1996). With respect to dictionary definitions, “[i]f more than one

dictionary definition is consistent with the use of the words in

the intrinsic record, the claim terms may be construed to encompass

all such consistent meanings.” Texas Digital Systems, Inc v

Telegenix, Inc, 308 F3d 1193, 1203 (Fed Cir 2002).

The court begins its construction of claim terms by

consulting intrinsic evidence of the meaning of disputed claim

terms, which includes the claims, the specification and the

prosecution history (if in evidence). Lacks Industries, Inc v

McKechnie Vehicle Components USA, Inc, 322 F3d 1335, 1341 (Fed Cir

2003) (citation omitted). “If upon examination of this intrinsic

evidence the meaning of the claim language is sufficiently clear,

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resort to ‘extrinsic’ evidence, such as treatises and technical

references, as well as expert testimony when appropriate, should

not be necessary.” Digital Biometrics, Inc, v Identix, Inc, 149

F3d 1335, 1344 (Fed Cir 1998). “[I]f after consideration of the

intrinsic evidence, there remains doubt as to the exact meaning of

the claim terms, consideration of extrinsic evidence may be

necessary to determine the proper construction.” Id.

“[A] court may constrict the ordinary meaning of a claim

term in * * * one of four ways[:]” (1) “if the patentee acted as

his own lexicographer and clearly set forth a definition of the

disputed claim in either the specification or prosecution history;”

(2) if the intrinsic evidence shows that the patentee distinguished

the term from prior art on the basis of a particular embodiment,

expressly disclaimed subject matter, or described a particular

embodiment as important to the invention; (3) “if the term chosen

by the patentee so deprives the claim of clarity as to require

resort to other intrinsic evidence for a definite meaning; and (4)

“if the patentee phrased the claim in step- or means-plus-function

format,” then “a claim term will cover nothing more than the

corresponding structure or step disclosed in the specification, as

well as equivalents thereto * * *.” CCS Fitness, Inc v Brunswick

Corp, 288 F3d 1359, 1366-67 (Fed Cir 2002) (internal citations and

quotation marks omitted).

Limitations from the specification, such as from the

preferred embodiment, cannot be read into the claims absent an

express intention to do so. Teleflex, Inc v Ficosa North Am Corp,

299 F3d 1313, 1326 (Fed Cir 2002) (“The claims must be read in view

of the specification, but limitations from the specification are

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not to be read into the claims.”). But “a construction that

excludes a preferred embodiment ‘is rarely, if ever, correct.’” 

C R Bard, Inc v United States Surgical Corp, 388 F3d 858, 865 (Fed

Cir 2004) (citing Vitronics, 90 F3d at 1583).

“A claim limitation that actually uses the word ‘means’

invokes a rebuttable presumption that [35 USC] § 112 P 6 applies.

By contrast, a claim term that does not use ‘means’ will trigger

the rebuttable presumption that § 112 P 6 does not apply.” CCS

Fitness, Inc v Brunswick Corp, 288 F3d 1359, 1369 (Fed Cir 2002).

Furthermore, the “presumption flowing from the absence of the term

‘means’ is a strong one that is not readily overcome.” Lighting

World, Inc v Birchwood Lighting, Inc, 382 F3d 1354, 1358 (Fed Cir

2004). 

With these legal principles in mind, the court now turns

to the construction of the disputed claim language of the three

patents-in-suit.

III

The ‘999 Patent

A

The parties parse the elements of ‘999 claims

differently, making it difficult directly to compare their proposed

term constructions. Claim 3 is illustrative of the parties’ main

disagreements: 

3. An endotracheal device comprising:

(a) a first tubular housing

having a first and second end,

the first end adapted for

insertion into a patient’s

trachea and the second end

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adapted for placement external

of the patient, the first

tubular housing defining lumen

means therethrough from the

first end to the second end;

(b) a second housing attached to

the second end of the first

tubular housing, said second

housing defining lumen means

therethrough communicating with

and forming an extension of the

lumen means of the first

housing, the lumen means of both

housings for allowing

bidirectional passage of air

into and out of the patient to

ventilate the patient’s lungs;

and

(c) colorimetric carbon dioxide

indicator means mounted within

the lumen means of said second

housing for determining the

presence of carbon dioxide

therein while still permitting

unimpeded bidirectional flow of

air through the housings to

ventilate the lungs of the

patient.

1. a first tubular housing

The parties do not dispute the construction of this term. 

Accordingly, the court declines to construe this term. 

2. lumen means therethrough from the first end to the second end

The parties disagree on how to define the lumen meansplus-function element of the asserted claims. Both parties agree

that the “lumen means” element of claim 3 is governed by 35 USC §

112, ¶6. Doc #60 at 15, Doc #65 at 2. Therefore, the court must

determine (1) the claimed function, and (2) the corresponding

structures recited within the patent specification that provide a

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means for performing the claimed function. See Kemco Sales, Inc v

Control Papers Co, Inc, 208 F3d 1352, 1361 (Fed Cir 2000). 

The first use of the term “lumen means” is contained in

clause (a) of claim 3 as shown above. “Therethrough” refers to the

first housing and indicates that the lumen proceeds from the first

end of the first housing through the second end of the first

housing. It is important to note that although the means term is

used in this clause, a function has not yet been defined for the

means and as such the means-plus-function element is incomplete for

analysis at this point in the claim.

3. a second housing

Plaintiffs propose that “a second housing” be construed

as “a housing, formed of one or more components, that need not be

in tubular configuration.” Doc #45 at 7. Defendants argue that a

second housing should be construed as “a single housing,” and

further argue that because the second housing defines a lumen means

which is an “extension” of the lumen means of the first housing,

“the combination must have a second end so that the combination is

a true extension of the first housing.” Doc #68 at 3. 

Defendants incorrectly attempt to add an additional

limitation in the form of a second end on the second housing. 

Claim 3 recites the second housing without reference to any ends. 

The plain meaning of “extension” does not require an extension to

be in the exact form of the shape it extends. Similarly,

plaintiffs’ attempt to broaden the definition of “housing” to

encompass housings made of one or multiple components is

unwarranted; the claim literally reads upon “a second housing.” 

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Whether the second housing can be made of more than one component

is an issue for the doctrine of equivalents, not claim

construction. See Dawn Equipment Co v Kentucky Farms, 140 F3d

1009, 1016 (Fed Cir 1998) (explaining that the trier of fact

applies the “function-way-result” test and the “insubstantial

differences test” to determine whether a claim is infringed under

the doctrine of equivalents). Thus, the court construes “second

housing” to mean a single housing, that need not be in tubular

configuration. 

4. attached

Plaintiffs argue that “attached” should be construed to

mean “connected directly or through one or more intermediate

structures.” Doc #45 at 7. Defendants propose “connected

directly.” Again, plaintiffs attempt to enlarge the scope of the

claim language to bring the doctrine of equivalents into literal

claim interpretation. After reading the term in light of the

specification and claim language, the court construes “attached” as

connected directly. Nowhere in the specification are the housings

described as “connected through one or more intermediate

structures.” Therefore, whether claim 3 reads upon a structure

connected through one or more intermediate structures is an issue

to be considered under the doctrine of equivalents by the trier of

fact, not by the court in claim construction. Dawn Equipment, 140

F3d at 1016. 

/

/

/

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5. lumen means therethrough communicating with and forming an

extension of the lumen means of the first housing

The second use of the term “lumen means” is contained in

clause (b) of claim 3 as shown above. In this clause,

“therethrough” refers to the second housing, which is not limited

by any language requiring either a first end or a second end. This

clause adds to the definition of the lumen means by showing that it

extends through the first housing and into the second housing. 

Although the lumen means is further defined by this language, a

function has not yet been identified at this point in the claim,

and as such the means-plus-function element is incomplete for

analysis as a whole. 

6. lumen means of both housings for allowing bidirectional 

passage of air into and out of the patient to ventilate the 

patient’s lungs

This language defines the function of the lumen means and

is the crux of parties’ dispute. The court is tasked with (1)

identifying the claimed function of the means, and (2) identifying

the corresponding structures in the specification that perform the

claimed function. Kemco Sales, Inc v Control Papers Co, 208 F3d

1352, 1361 (Fed Cir 2000). Accordingly, to be claimed in claim 3,

the corresponding structures of the lumen means must perform the

function of “allowing bidirectional passage of air into and out of

the patient to ventilate the patient’s lungs.” 

Plaintiffs argue for a plain meaning construction of the

function. Defendants propose a construction that removes the

permissive word “allowing” and requires that the lumen means have a

second end. Doc #68 at 6. As discussed above, neither a first nor

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a second end of the second housing is recited in the claim and

therefore, the court rejects defendants’ arguments regarding the

nature of the lumen means “extension” through a second end of the

combination. Defendants additionally argue that because the patent

examiner required an amendment to recite that the lumen means of

“both housings allow the bidirectional flow of air,” the plaintiffs

are barred by prosecution history estoppel from claiming all of the

disclosed embodiments. Doc #68 at 6. Specifically, defendants

argue that this amendment requires the corresponding structures to

be limited to those describing “one continuous lumen means,” and

therefore, the embodiment depicted in figure five is excluded. Id

at 6-7. 

But it is a non sequitur to argue that if (1) both

housings allow bidirectional flow, and (2) the lumen means of the

second housing is an extension of the lumen means of the first

housing; then the extension through the second housing must be in

the same direction, shape and manner as the lumen means of the

first housing so as to require bidirectional flow through both

housings. “Allowing” is a permissive term, and the plain meaning

of the word and the patent specification lead the court to accept

the plain meaning construction. Therefore, the court adopts

plaintiffs’ proposed construction and construes the function of the

corresponding structures to be “allowing bidirectional passage of

air into and out of the patient to ventilate the patient’s lungs.” 

 Plaintiffs propose that this means-plus-function clause

be construed so that the corresponding structures of the lumen

means of both housings are “the hollow bodies of the first and

second housings described and illustrated in the specification, and

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their equivalents that define one or more luminal air flow paths or

channels.” Doc #45 at 9. Defendants propose that “lumen means” as

recited in claims 3, 6, 7, 10, 13, 15, 17, 20-22 and 25 be

construed as “limited to the spaces defined by the rigid structures

described in the specification of the ‘999 patent” and further

modified by the limitations in each claim. Doc #60 at 15. 

Aditionally, defendants reiterate their argument that “both

housings” in combination must be limited to structures with a first

end and a second end in order to allow bidirectional passage of

air, which, since the housings define the lumen means, requires

that it have a first and second end as well. Id at 17.

In construing a § 112, ¶6 claim, a court may not import

functional limitations that are not recited in the claim, or

structural limitations from the written description that are

unnecessary to perform the claimed function. Wenger Manufacturing

Inc v Coating Machinery Systems, Inc, 239 F3d 1225, 1233 (Fed Cir

2001). Defendants’ construction attempts to introduce an unclaimed

limitation to the structures defined by the lumen means in the form

of the adjective rigid. Similarly, defendants’ construction

attempts to require the limitation of a second end on the second

housing, which is unsupported by the claim language.

Plaintiffs’ proposed construction, however, proposes the

introduction of additional language, so that the lumen means

explicitly defines “one or more luminal air flow paths or

channels.” Doc #45 at 9. Claim 3 contains no mention of air flow

paths or channels, and thus plaintiffs’ construction impermissably

introduces unclaimed structure to clarify the means-plus-function

element. Therefore, the court construes the corresponding

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structures of the “lumen means” to include all structures described

in the patent specification going through a first end of a first

housing through a second end of the first housing and communicating

with and extending through a second housing -- regardless of air

flow paths or channels.

In sum, the court construes the lumen means-plus-function

element of claim 3 to read upon: all structures described in the

specification of the ‘999 patent (1) defined by going through a

first end of a first housing through a second end of the first

housing, and communicating with and extending through a second

housing (2) that perform the function of “allowing bidirectional

passage of air into and out of the patient to ventilate the

patient’s lungs.” 

7. colorimetric carbon dioxide indicator means mounted within the

lumen means of said second housing

Like the lumen means in clauses (a) and (b), the

indicator means-plus-function element is incomplete for analysis

until its function has been identified. In light of the

corresponding structures that perform the function identified later

in the claim, this clause limits the indicator means of claim 3 to

those structures “mounted within the lumen means of the second

housing.” Defendants, again relying on a definition of lumen means

that requires a second end and bidirectional flow through all

sections, argue that certain embodiments shown in the ‘999 figures

are not claimed in claim 3. As addressed above, this argument is

in error. Therefore, “mounted within the lumen means of the second

housing” is simply construed as the plain meaning of “mounted

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within” in light of the court’s constructions of second housing and

lumen means above.

8. for determining the presence of carbon dioxide therein

This clause defines the function performed by the

colorimetric carbon dioxide indicator means (“indicator means”). 

The parties do not argue over the function itself. Rather, they

disagree about which corresponding structures disclosed in the

specification are capable of performing this function, i e, which

structures determine the presence of carbon dioxide within the

lumen means of the second housing. Plaintiffs argue that the

indicator means is described by the specification as “hydrazine and

other disclosed compounds that cause a pH change * * * in

combination with a colorimetric pH indicator.” Doc #65 at 8. 

Defendants argue that the indicator means should be “limited to an

indicator substance in a solid support where the indicator

substance is limited to the carbon dioxide indicator composition

disclosed in the specification, namely, hydrazine, or its

equivalents.” Doc #60 at 20.

Defendants’ attempt to introduce the “in a solid support”

limitation to the claim is in error. The court will not introduce

an unclaimed limitation into a means plus function claim, even if

the limitation is recited in the specification. Wenger

Manufacturing, 239 F3d at 1233. Therefore, to the extent that the

patent specification describes corresponding structures capable of

performing the claimed function within the limitations of the

claim, those corresponding structures are claimed by claim 3,

whether or not they are disclosed as being within a solid support. 

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Defendants attempt to limit the corresponding structures

of the indicator means to hydrazine on the basis that the inventors

used hydrazine in the actual reduction to practice. Doc #60 at 20. 

Defendants argued at oral argument that in order to perform the

function of the means-plus-function clause, the corresponding

structure must “work.” Plaintiffs argued that actual reduction to

practice is irrelevant because everything disclosed in the patent

application is treated as constructively reduced to practice, and

as such, it is a proper subject matter for corresponding

structures. Plaintiffs also properly argued that defendants’

actual-reduction-to-practice argument is an invalidity argument (i

e, if a corresponding structure is incapable of performing the

claimed function, then the claim is invalid under 35 USC § 112, ¶1

because it fails to enable one skilled in the art to practice the

invention), which is not for the court to consider during claim

construction.

Accordingly, the court adopts plaintiffs’ contruction and

construes “colorimetric carbon dioxide indicator means” to cover

combinations of (1) a compound disclosed in the patent

specification for causing a pH change with (2) a colorimetric pH

indicator disclosed in the patent specification for determining the

presence of carbon dioxide within the lumen means of the second

housing. 

9. while still permitting unimpeded bidirectional flow of air 

through the housings to ventilate the lungs of the patient.

Defendants argue, based on dictionary definitions and

prosecution history estoppel, that “unimpeded” should be construed

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as “unrestricted.” Doc #60 at 18; Doc #68 at 8. Defendants also

point to a dictionary defintion in support of this construction,

where impede means “to interfere with or get in the way of the

progress of,” or is a synonym for “hinder.” Doc #60, Ex 13. 

Defendants’ strongest patent prosecution history estoppel

argument is based upon the patent examiner’s reexamination analysis

of the term “impeded” as it was used to distinguish claims from the

prior art. Doc #61, Ex 25 at 2. Pursuant to 35 USC § 302, ICOR

AB, a Swedish corporation and apparently a non-party to this

litigation, requested a reexamination of the ‘999 patent in light

of several previously unconsidered references. Doc #61, Ex 23. In

its request for reexamination, ICOR AB argued for roughly the

opposite construction to defendants’ proposed construction, asking

the examiner to find that this clause was essentially a nonlimitation because “no patient can breath through an impediment.” 

In response to this argument, the examiner considered the Adriani

reference, which described soda lime crystals impregnated with dyes

that changed colors in response to pH changes within a to-and-fro

cannister through which a patient under anesthesia breathed. File

History SN 90/003,808, at DFH00835-842.

In confirming patentability after reexamination, the

examiner noted: 

The claims do not require the patient breath[e]

through a[n] impediment or that merely

bidirectional flow be permitted but rather to

permit unimpeded flow. Bidirectional flow may

still exist where there is an impediment but be

retarded or hindered thereby, i.e. a lesser

degree of bidirectional flow exists or impeded

bidirectional flow exists. Requestor’s

interpretation of “impeded”, i.e. not allowing

any flow, and thus the converse term

“unimpeded” differs in scope from the broadest

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reasonable interpretation of such terms.”

Doc #62, Ex 25 at 2.

In other words, in confirming patentability of the ‘999

patent over the prior art submitted in the reexamination request,

the examiner found that this limitation’s recitation of “unimpeded”

meant the bidirectional flow must be “unrestricted” or the converse

of “not allowing any flow.” Id. This determination allowed the

patent claims to remain patentable in light of the Adriani

reference whereby the airflow through the canister resulted in

“impedance to the flow of gases” both from the soda lime granules

in the inhaler as well as from the valves and tubes causing

“turbulent flow and friction.” DFH000840. In light of the

dictionary definitions submitted by defendant and the plain meaning

of the claim language, the court agrees with the examiner’s

construction of the word “unimpeded.”

While the examiner’s reexamination construction is

instructive on the interpretation of “unimpeded,” it is not

controlling. This is not a case of prosecution history estoppel,

because here, the patentee did not “forgo an appeal and submit an

amended claim, [which was] taken as a concession that the invention

as patented does not reach as far as the original claim.” Festo

Corp v Shoketsu Kinzoku Kogyo Kabushiki Co, 535 US 722, 734. 

Defendants correctly argue that “claims may not be construed [by

the inventor] one way in order to obtain their allowance and in a

different way against accused infringers.” Doc #60 at 19. This

principle applies with equal force to arguments made by a patentee

to sustain the patentability of claims during reexamination. 

Spectrum International v Sterilite Corp, 164 F3d 1372, 1379. 

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But the patentee is under “no obligation to respond to an

examiner's statement of Reasons for Allowance, and the statement of

an examiner will not necessarily limit a claim.” Eolas Techs, Inc

v Microsoft Corp, –– F3d –– , ––; 2005 US App LEXIS 3476, 31 (Fed

Cir 2005) (quoting ACCO Brands, Inc v Micro Security Devices, Inc,

346 F3d 1075, 1078 (Fed Cir 2003)). In the case at bar, defendants

have not shown that patentees made a limitation in acceptance of

the examiner’s reexamination construction or advanced an argument

to overcome the prior art. In fact, the reexamination history

submitted to the court does not contain any arguments advanced by

the patentee in response to ICOR’s ex parte reexamination notice. 

Doc #62, Ex 23-25; File History SN 90/003,808 binder. 

In contrast to reexamination, the patentee did assert

arguments to the patent office during ordinary prosecution of this

claim limitation. Those arguments show that the patentee intended

this limitation to mean that the bidirectional flow of air to the

patient must be unimpeded. Doc #61 Ex 19 at 13. But the

inventor’s arguments also make it clear that the limitation was

meant to require unimpeded airflow only through the bidirectional

pathway 

to the patient, and did not necessarily apply to other airflow:

In the same fashion, while flow may be

partially impeded through the side-arm 24 of

the figure 5 embodiment (e g, when cap 40 is in

place), in no way is the bidirectional flow of

air to the patient impeded, as represented by

flow through the primary luminal path 6.

Id.

Therefore, the court adopts defendants’ construction of

the term “unimpeded,” but interprets the entire limitation in light

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of the patent prosecution history and specification such that it is

only the bidirectional passage of air to the patient that must be

unrestricted. 

B

At oral argument, the parties agreed that construing

claim 3 would resolve the majority of issues relating to the ‘999

patent. Plaintiffs’ opening brief argues for construction of three

terms outside of claim 3 of the ‘999 patent: “indicator substance”

as it first appears in claim 7; “a passage therethrough which

defines the housing lumen means” as it first appears in claim 8;

and “within the passage of the connector” as it first appears in

claim 8.

1. indicator substance

Defendants argue that “indicator substance,” as it first

appears in claim 7, should be construed as a means-plus-function

element. Doc #68 at 9. Furthermore, defendants argue that the

corresponding structures of the indicator substance should not

encompass all indicators listed in the specification, but should

instead be limited to “hydrazine, or its equivalents.” Doc #68 at

9. Plaintiffs’ proposal appears to accept that “indicator

substance” should be construed as a means-plus-function element

because it is written in terms of “the structures and materials

described in the specification * * * that perform the function of

providing a visually observabe color change in the presence of air

that contains carbon dioxide in a concentration that is normally

present in expired respiratory gas.” Doc #45 at 15. 

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The fundamental difference between the proposed

constructions is that plaintiffs’ proposal both defines the

function performed by the indicator substance and includes all

corresponding structures listed in the patent specification that

perform that function, while defendants’ construction neglects to

define the function and attempts to limit the corresponding

structures to hydrazine or its equivalents. 

Defendants do not challenge the function proposed by

plaintiffs, and they summarily state that the indicator chemistry

must be limited to hydrazine or its equivalents, the same argument

that the court has rejected in construing “for determining the

presence of carbon dioxide therein.” Doc #68 at 9. Defendant

further argues that “indicator substance” should be limited to “an

indicator substance in a solid support.” Doc #60 at 20. This

interpretation directly contradicts the language of claim 7, which

states that the indicator means “comprises a colorimeteric carbon

dioxide indicator substance and solid support means.” It is

illogical to interpret “indicator substance” as requiring a solid

support when the claim explicitly lists the element of a solid

support on its own. 

Plaintiffs’ proposal contains the language, “and their

equivalents.” Doc #45 at 15. It is well settled that “for the

court to find infringement the plaintiff must show the presence of

every element or its substantial equivalent in the accused device.” 

Lemelson v United States, 752 F2d 1538, 1551 (Fed Cir 1985). If

necessary, the finder of fact will consider the doctrine of

equivalents as it pertains to all claims; accordingly, the court

will not construe any terms by using unneccessary language

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regarding equivalents. 

The court adopts plaintiffs’ construction with the

exception of the equivalents language and construes “indicator

substance” as “the structures and materials described and

illustrated in the specification that perform the function of

providing a visually observable color change in the presence of air

that contains carbon dioxide in a concentration that is normally

present in expired respiratory gas.”

2. a passage therethrough which defines the housing lumen means, and the indicator means is mounted within the passage of the

connector.

 Plaintiffs propose that “passage,” as it first appears in

claim 8, be construed as “one or more passages that extend through

the tubing connector and define the lumen means of the second

housing.” Doc #45 at 15. Defendants argue that “a passage,” when

read in light of the rest of the claim language -- particularly,

“within the passage” -- must be limited to a single passage. Doc

#68 at 9-10. Defendants’ attempt to limit claim 8 to read upon

only those second housings in which the tubing connector has one

and only one passage therethrough is misplaced. Nothing in the

claim language suggests this limitation. 

The reference to “the passage” simply requires that the

indicator means is mounted within the passage that satisfies the

“passage therethrough which defines the housing lumen means”

requirement of this claim; it says nothing about excluding

alternate embodiments that otherwise meet all of the claim

elements. Accordingly, the court construes claim 8 to read upon

(1) any endotracheal device read upon by claim 3 (2) where the

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second housing includes a tubing connector having a passage

therethrough which defines the housing lumen means (as construed

above) (3) and the indicator means (as construed above) is mounted

within the passage of the connector.

III

The ‘075 Patent

The parties’ central disagreement about the construction

of claims in the ‘075 patent concerns water, and the terms used to

describe its presence in the claimed invention, an apparatus for

determining whether respiratory gas is present in a gaseous sample. 

Terms construed for the ‘075 patent have the same construction in

the ‘002 patent unless otherwise stated. Claim 1 is illustrative:

A method for determining whether a gaseous

sample contains a predetermined concentration

of carbon dioxide, comprising the step of:

contacting the gaseous sample with a dry

reagent detector comprising a carrier having an

aqueous indicating composition applied thereto

for providing an indication of the presence of

the predetermined concentration of carbon

dioxide in the sample within a diagnostically

effective period of time when the carbon

dioxide concentration in the sample is at least

about 2% and providing said indication after

about ten minutes when the carbon dioxide

concentration in the sample is about 0.03%.

1. dry reagent detector

The parties agree that the term “dry reagent detector,”

which first appears in claim 1, includes detectors that contain

some water. Doc #68 at 11, n5. Therefore, the court adopts

plaintiff’s construction, “a detector having an immobilized reagent

with excess liquid removed but which may contain some water.” Doc

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#45 at 19.

2. aqueous indicating composition

Plaintiffs argue for the construction of “an indicating

composition containing some water.” Doc #45 at 19. Defendants

argue that this term refers to “an indicator composition that

functions in liquid water.” Doc #68 at 12. Both parties dedicated

a considerable portion of their briefing and oral argument to the

definition of the term “aqueous.” In doing so, both parties

pointed to relevant portions of the specification, expert testimony

and dictionary definitions in support of their proposed

constructions. Markman Hearing, plaintiffs’ slides 25-27;

defendants’ slides 49-54.

Plaintiffs’ construction, as the broader of the two, does

not exclude any of the dictionary definitions, expert testimony or

portions of the specification cited by defendants. On the other

hand, defendants’ construction requires limitation of the

dictionary definition submitted by plaintiff and discounts portions

of the testimony of the named inventor. Neither party has shown

that the other party’s construction directly conflicts with the

specification or the prosecution history. 

The Federal Circuit has held that “[i]f more than one

dictionary definition is consistent with the use of the words in

the intrinsic record, the claim terms may be construed to encompass

all such consistent meanings.” Texas Digital Systems, Inc v

Telegenix, Inc, 308 F3d 1193, 1203 (Fed Cir 2002). On this legal

principle alone, the court would adopt plaintiffs’ proposed

construction. Additionally, defendants’ use of “functions in”

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imports a limitation to the claim language that is neither in the

plain language meaning of the claim, nor found in any of the

submitted dictionary definitions. Accordingly, the court adopts

plaintiffs’ proposition and construes aqueous indicating

composition as “an indicating composition containing some water.”

3. and providing said indication after about ten minutes when the

carbon dioxide concentration in the sample is about 0.03% 

Defendants argue that the plain meaning construction of

“after about ten minutes” is equivalent to “at or about ten

minutes.” Doc #68 at 14. Plaintiffs contend that the plain

meaning of “after” is not equivalent to “at or about.” Doc #45 at

20. The prosecution history shows that the patent examiner

requested an examiner’s amendment to change the claim language from

“but not providing said indication for more than about ten minutes”

to its present form. Doc #62, Ex 27 at 2, Exs 28-29. The patentee

had a right to object to the examiner’s requested amendment and

appeal the examiner’s rejection but opted instead to accept the

amendment so that the claim would be allowed. Id. When a patentee

forgoes the option to appeal and instead submits an amended claim,

it is “taken as a submission that the invention as patented does

not reach as far as the original claim.” Festo Corp v Shoketsu

Kinzoku Kogyo Kabushiki Co, 535 US 722, 734 (2002). 

Plaintiffs’ construction impermissably attempts to

recapture the open-ended limitation that was given up during patent

prosecution in order to get the claims in a condition for

allowance. Accordingly, the court adopts defendants’ proposal and

construes “after about ten minutes” to mean “at or about ten

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minutes.”

4. a dried non-volatile indicating element

Defendants contend that “indicating element,” as it first

appears in asserted claim 18, must be construed as a means-plusfunction element under § 112, ¶6 because the indicating element is

described “exclusively by the function it performs.” Doc #68 at

11. The absence of the word “means” in a claim element creates a

presumption that the element should not be construed under 35 USC §

112, ¶6. Linear Technology Corp v Impala Linear Corp, 379 F3d

1311, 1319 (Fed Cir 2004). To overcome this presumption, the

proponent of interpretation under § 112, ¶6 has the burden of

showing that the claim “fails to recite sufficiently definite

structure or recites a function without reciting sufficient

structure for performing that function.” CCS Fitness Inc v

Brunswick Corp, 288 F3d 1359, 1369 (Fed Cir 2002) (internal

citations omitted). Furthermore, this presumption is “a strong one

that is not readily overcome.” Lighting World, Inc v Birchwood

Lighting Inc, 382 F3d 1354, 1358 (Fed Cir 2004). 

Defendants assert that it is “impossible for one

ordinarily skilled in the art to identify what materials are being

claimed.” Markman Hearing, defendants’ slide 72. However,

defendants do not point to any evidence, expert testimony or

otherwise, in support of that assertion. Doc #60 at 22-23, Doc #68

at 11. Instead, defendants argue that plaintiffs rely improperly

on Dr Kiser’s testimony that the claim does recite sufficient

structure. Doc #68 at 11. This argument is flawed because it is

defendants who have the burden, not plaintiffs. Because defendants

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do not demonstrate that the claim “fails to recite sufficiently

definite structure or recites a function without reciting

sufficient structure for performing that function,” the court need

not address Dr Kiser’s testimony to construe this claim.

Accordingly, the court adopts plaintiffs’ proposed

construction, and construes a dried non-volatile indicating element

as “an immobilized indicating element that does not readily

evaporate at normal temperatures and pressures and has had excess

liquid removed but which may contain some water.” Doc #45 at 16. 

 

5. aqueous alkaline solution

The parties agree that “alkaline” means “a pH greater

than 7.” Doc #68 at 15 n8. Defendants point to several

authorities that demonstrate that the term “aqueous solution,” as

it first appears in claim 21, is a term of art in chemistry that

defines a solution where water is the primary solvent. Doc #68 at

15; Doc #60 Ex 9 at 142, Ex 10 at 37, Ex 11 at 330 Ex 12 at 28. 

Accordingly, the court adopts defendant’s construction, and

construes aqueous alkaline solution as “a solution of liquid water

and one or more solutes, the solution having a pH greater than 7.” 

At oral argument, defendants argued that accepting their

construction of “aqueous solution” requires the court to accept

their construction of “aqueous indicating composition,” as

“functions in liquid water.” Doc #68 at 12. This argument is

flawed, however, because defendants fail to show that “aqueous

indicating composition,” is related to the term of art of “aqueous

solution.” Thus, the court’s construction of “aqueous indicating

composition” as a phrase in which the adjective “aqueous” modifies

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the term “indicating composition” does not conflict with its

construction of “aqueous solution” as a term of art.

6. produces a response for a second predetermined period of time

longer than said first predetermined period of time when the

composition is exposed only to concentrations of carbon

dioxide of no more than about 0.03%

Plaintiffs contend that this limitation, first recited in

claim 21, does not require a limiting construction of “the first

predetermined period of time,” “the second predetermined period of

time” and “a response.” Plaintiffs’ most convincing argument rests

upon the doctrine of claim differentiation. Doc #45 at 22. For

example, claim 25 (a dependent claim of claim 21) requires the

“second predetermined period of time” to be “longer than 10

minutes.” Therefore, the “second predetermined period of time” in

claim 21 must include periods other than those longer than 10

minutes. 

Defendants propose a more limited construction based on

the specification such that “the second predetermined period of

time” is approximately ten minutes and “a response” is a false

positive. Doc #60 at 26. Additionally, defendants argue that if

plaintiffs’ broad construction is adopted, the claim is indefinite

and invalid. Doc #68 at 15-16. 

Whatever the merit of defendants’ invalidity argument,

claim construction is a distinct issue, and the court may not

import unclaimed limitations from the specification to put a saving

construction on a claim. EI du Pont, 849 F2d at 1433. 

Accordingly, the court construes this limitation according to the

plain meaning of the claim language in light of the doctrine of

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claim differentiation.

 IV

The ‘002 patent

The terms construed above for the ‘075 patent are

identically construed for the ‘002 patent. Additional terms in the

‘002 patent also require construction. Claim 1 is illustrative:

Apparatus for determining whether a gaseous

sample contains a predetermined concentration

of carbon dioxide, comprising: 

means for introducing the gaseous sample into

an enclosure;

dry reagent detector means within the enclosure

for producing a response to the presence of

said predetermined concentration of carbon

dioxide in the sample, said detector means

comprising a carrier having a aqueous

indicating composition applied thereto, said

indicating composition providing an indication

of the presence of said predetermined

concentration of carbon dioxide in the sample

within a diagnostically effective period of

time when the cargon dioxide concentration in

the sample is at least about 2% and providing

said indication after about ten minutes when

the carbon dioxide concentrationin the sample

is about 0.03%. 

1. means for introducing the gaseous sample into an enclosure

The parties agree that this limitation should be

construed under 35 USC § 112, ¶6. Doc #68 at 16. Defendants argue

that the term “enclosure” should be limited to describe “a

structure capable of collecting a suitable sample of gas to be

tested.” Doc #68 at 16. Plaintiffs seek a plain meaning

interpretation, but contend that the corresponding structure

“includes the enclosure depicted in figure 1 and the structure of a

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double ended enclosure with openings on each end that is described

at column 2, lines 25-57.” Because there does not appear to be a

significant disagreement between the parties, the court adopts

defendant’s proposal and construes the limitatation as, “the

structures and materials described and illustrated in the

specification for performing the function of introducing the

gaseous sample into a structure capable of collecting a suitable

sample of gas to be tested.”

2. means responsive to said change in pH for providing an

indication within a predetermined period of time of the

presence of said predetermined concentration of carbon dioxide

in the sample and providing said indication after about ten

minutes when the concentration of carbon dioxide in the sample

is substantially less than said respiratory concentration.

The parties agree that this limitation to claim 23 should

be construed under 35 USC § 112, ¶6 and that the court is tasked

with (1) identifying the claimed function and (2) identifying the

corresponding structures disclosed in the specification for

performing that function. Kemco Sales, Inc v Control Papers Co,

Inc, 208 F3d 1352, 1361 (Fed Cir 2000). The court construes the

function of this limitation to be (1) providing an indication

within a predetermined amount of time * * * and (2) providing said

indication in about 10 minutes when the concentration of carbon

dioxide in the sample is substantially less than said respiratory

concentration. Therefore, the structures disclosed in the

specification are within the scope of this claim if, and only if,

the specification adequately describes and links the structure(s)

to the claimed function. Medical Instrumentation & Diagnostics

Corp v Elekta AB, 344 F3d 1205, 1211 (Fed Cir 2003). 

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Defendants contend that the corresponding structures

listed in the patent that perform this function are “water soluble

indicators,” which are recited in column 6, lines 56-69 of the

patent. Doc #60 at 29. Plaintiffs assert that the pH indicators

disclosed in column 7, lines 1-24 are the proper corresponding

structures. Doc #45 at 24. Additionally, plaintiffs ask the court

to consider expert testimony as to whether one skilled in the art

would understand that the structures in column 7 perform the

claimed function. Doc #45 at 24. 

“Corresponding structure need not include all things

necessary to enable the claimed invention to work. It is equally

true, however, that corresponding structure must include all

structure that actually performs the recited function.” Cardiac

Pacemakers, Inc v St Jude Medical, Inc, 296 F3d 1106, 1119 (Fed Cir

2002). Defendants argue that the corresponding structure must

include a “chemical treating composition,” as disclosed in column

6, lines 56-54. Defendants also ask the court to construe “means

responsive to said change in pH for providing an indication * * *”

to exclude the “suitable pH-sensitive indicators” recited in the

specification in favor of “suitable chemical treating

composition[s].” Doc #68 at 17. 

It is well established that the corresponding structure

to a function must actually perform the recited function, and “not

merely enable the pertinent structure to operate as intended.” 

Asyst Techs, Inc v Empak, Inc, 268 F3d 1364, 1371 (Fed Cir 2001).

Thus, in order to determine whether defendants’ asserted chemical

compositions are corresponding structure, the inquiry is whether

the chemical treating compositions enable the performance of the

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claimed function within the time limitations set forth in the

claim, or whether they perform it themselves. 

Although Kemco Sales does assign the court -- as part of

claim construction -- the task of determining which corresponding

structures are associated with a means-plus-function limitation

during claim construction, the court notes the pertinent inquiries

regarding corresponding structures may be inherently factual and

ill-suited to determination as a matter of law. Here, the issue is

one of fact, namely: do the disclosed structures merely enable the

claimed function to be performed or do they perform it themselves? 

For this limitation, it is impossible for the court to

identify the corresponding structures short of a full-blow inquiry

into arguments of invalidity for lack of enablement. Patent claims

are presumed valid, and “[i]nvalidity for lack of enablement is a

conclusion of law [that] must be supported by facts proved by clear

and convincing evidence.” Northern Telecom, Inc v Datapoint Corp,

908 F2d 931, 941 (Fed Cir 1990). Accordingly, at this time, the

court defers the identification of the corresponding structures by

line number and instead adopts plaintiffs’ construction after

removing the equivalents language: “the structures and materials

described and illustrated in the specification for performing the

function of providing an indication within a predetermined period

of time of the presence of said predetermined concentration of

carbon dioxide in the sample and providing said indication after

about ten minutes when the concentration of the carbon dioxide in

the sample is substantially less than said respiratory

concentration.” 

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3. detector means

Claim 1 recites a “dry reagent detector means * * * for

producing a response to the presence of said predetermined

concentrations of carbon dioxide in the sample.” Claim 24 recites

“detector means * * * for responding to the presence of the

predetermined concentration of carbon dioxide.” The presence of

the word “means” in a claim limitation creates a rebuttable

presumption that the claim element should be construed under 35 USC

§ 112, ¶6 as a means-plus-function element. Linear Technology Corp

v Impala Linear Corp, 379 F3d 1311, 1319 (Fed Cir 2004).

Plaintiffs argue that sufficient structure is recited in

the language following the means-for language to overcome the

presumption that § 112, ¶6 applies. Doc #45 at 24. Specifically,

plaintiffs point to two phrases as denoting structure: (1) “a

carrier having an aqueous indicating composition applied thereto”

in claim 1; and (2) “a carrer to which a non-volatile indicating

composition has been applied” in claim 24. Id. 

To determine whether a term denotes sufficient structure,

a court should inquire into whether “a term, as a name for the

structure, has a reasonably well understood meaning in the art.” 

Watts v XL Sys, 232 F3d 877, 881 (Fed Cir 2000). Neither party has

presented evidence on whether “carrier” (claims 1 and 24) has a

reasonably well understood meaning in the art that denotes

structure or a class of structures. Plaintiffs point to other

construed terms to argue that the indicating composition terms

would denote sufficient structure to one of reasonable skill in the

art. Doc #45 at 24. 

Plaintiffs argue that “non-volatile indicating

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composition” in claim 1 should be construed consistently with

“dried non-volatile indicating element” in claim 18 of the ‘075

patent. But the court construes claim 18 of the ‘075 patent in

view of the burden on defendants, whereas the construction sought

by plaintiffs in claim 1 of the ‘002 patent places the burden on

plaintiffs. The court’s construction of claim 18 of the ‘075

patent does not establish that the term “non-volatile indicating

element” was a name for a structure sufficiently well understood by

those skilled in the art. And in any event, “dried non-volatile

indicating element” is not the same term as “non-volatile

indicating composition.” By relying upon the court’s construction

of a claim 18 of the ‘075 patent in isolation, plaintiffs have not

met their burden with respect to the term “non-volatile indicating

composition.” 

“Aqueous indicating composition” is construed in claim 1

of the ‘075 patent as “an indicating composition containing some

water.” Plaintiffs rely upon this construction to overcome the

presumption that “detector means” in claim 24 is a means-plusfunction limitation. But the only structure supplied in this

construction is “containing some water,” shedding no light on

whether the term “indicating composition” would denote sufficient

structure to one of reasonable skill in the art. Therefore, the

court finds that plaintiff has not overcome the presumption that

the term “detector means” in claim 24 of the ‘002 patent should be

construed pursuant to 35 USC § 112, ¶6.

Accordingly, the court construes the “dry reagent

detector means” of claim 1 and the “detector means” of claim 24 to

be limited to those structures and materials described in the ‘002

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patent specification and figures that are disclosed as performing

the plain meaning functions described in those claims, subject to

the additional limitations listed in each claim.

V 

Because the court has not relied upon Dr Kiser’s expert

declaration, the motion to strike portions of Dr Kiser’s

declaration (Doc #70) is TERMINATED as moot. 

IT IS SO ORDERED.

 

VAUGHN R WALKER

United States District Chief Judge

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