University of Manitoba, The v. Dragerwerk Ag & Co. KGaA et al

Filing 91

FINAL CLAIM CONSTRUCTION ORDER by Chief Judge Ralph R. Erickson.(SH)

IN THE UNITED STATES DISTRICT COURT
FOR THE DISTRICT OF NORTH DAKOTA
NORTHEASTERN DIVISION
The University of Manitoba, a Manitoban
Body Corporate,
Plaintiff,
vs.
Drägerwerk AG & Co. KGaA, a German
Limited Partnership, and Draeger Medical,
Inc., a Pennsylvania Corporation,
Defendants.

)
)
)
)
)
)
)
)
)
)
)
)

Civil Case No. 2:13-cv-48

Final Claim Construction of “Controlled Life Support Conditions” in
Claims 1, 2, and 3 of U.S. Patent No. 5,647,350 (the ‘350 Patent”)
This matter is before the Court on the issue of patent claim construction pursuant to
Markman v. Westview Instruments, Inc.,1. The subject invention generally pertains to varying
the flow of biological fluids to an organ during “controlled life support conditions.” Plaintiff
initially sued Drägerwerk AG & Co. KGaA, a German Limited Partnership, and Draeger
Medical, Inc., a Pennsylvania Corporation. The Court dismissed Drägerwerk AG & Co. KgaA
for lack of personal jurisdiction.2
On February 18, 2014, Plaintiff the University of Manitoba filed its claim construction
brief.3 Defendant Draeger Medical, Inc. filed its responsive claim construction brief on March 4,

1

517 U.S. 370 (1996).

2

Doc. #80.

3

Doc. #69.

1

2014,4 and an amended responsive brief on March 6, 2014.5 The University of Manitoba filed a
reply brief on March 11, 2014.6 A Markman7 hearing was held on April 17, 2014 on the disputed
claim term “controlled life support conditions”.
The Court inquired of the parties whether they had an interest in receiving the Court’s
tentative draft rulings on claim construction before the scheduled Markman hearing. Courts have
found this procedure useful for focusing the parties’ arguments on true disputes about the
construction of pertinent claims as well as on specific parts of the court’s tentative claim
constructions where they believe the court had gone wrong. Both sides in this case
recommended this Court follow such a procedure. The Court provided the parties with a
tentative draft ruling on claim construction prior to the Markman hearing.
At the Markman hearing, Draeger sought to present three new pieces of evidence: (1) an
article entitled Combined Unilateral High Frequency Jet Ventilation and Contralateral
Intermittent Positive Pressure Ventilation authored by B.A. Morgan, D. Perks, I.D. Conacher,
and M.L. Paes; (2) United States Patent No. 6,269,813 B1 (Fitzgerald); and (3) United States
Patent Application 2011/0180063 A1 (Hunsicker)8. The University of Manitoba objected to
introduction of the new evidence. The Court found that the evidence was not timely disclosed,
and Draeger failed to provide an adequate explanation for the late disclosure. The Court

4

Doc. #74.

5

Doc. #75.

6

Doc. #76.

7

517 U.S. 370 (1996).

8

Doc. #90.

2

indicated at the hearing that it either would decline to consider the new evidence, or it would
allow the University of Manitoba an opportunity to present a written response to the new
evidence. The University of Manitoba elected not to respond to the new evidence. The Court
finds that the newly presented evidence does not enlighten the claim construction issues, and it
has not relied on the evidence to construe the claims. The record now being complete, the Court
issues this final claim construction order.
At the Markman hearing the University of Manitoba reiterated that the term “primary”
must be given its plain and ordinary meaning, and the Court’s tentative claim construction
improperly ignores that meaning. The University of Manitoba also asserted that the Court erred
in its tentative analysis when it relied on “sound bites” in the prosecution history and failed to
consider the entire history. In doing so, the University of Manitoba contends that the Court
incorrectly used the prosecution history to vary the plain language of the claims. The Court, after
reexamining the claims and the prosecution history, restudying the prior art, and carefully
considering the University of Manitoba’s arguments, finds that the Court’s tentative analysis
continues to be correct.
BACKGROUND
In applying the Phillips9 methodology, the Court’s recitation of the factual background
focuses on the patent-in-suit, including the words of the patent claims at issue in this
infringement suit. The prosecution history is not recounted here. Any pertinent parts of the
prosecution history is reserved and will be recounted when, and if, resort to the prosecution
history for guidance is appropriate.

9

Phillips v. AWH Corp., 415 F.3d 1303 (Fed. Cir. 2005).

3

1.

The Parties
The University of Manitoba (hereafter “the U of M”) is located in Winnipeg, Manitoba,

Canada. The U of M is the assignee of U.S. Patent No. 5,647,350 (the ‘350 Patent), the patentin-suit.
Draeger Medical, Inc. (hereafter “Draeger”) is a Pennsylvania Corporation with a
principle place of business in Telford, Pennsylvania.10 The U of M alleges Draeger sells a
“Variable Pressure Support” (“VSP”) option on some of its medical ventilators in the United
States. Draeger asserts that the VSP option on its ventilators only functions when there is
“patient breathing efforts.” Thus, according to Draeger, once a patient’s breathing effort is
detected, the VSP provides partial assistance to support the patient’s own breathing. If the
patient ceases breathing efforts, Draeger’s ventilator alarms out of the VSP mode and begins a
different mode of controlled patient ventilation. The U of M alleges that Draeger’s ventilator
containing the VSP option infringes on its patent.
2.

The Patent-in-Suit
a. The Inventors and Dates of Filing and Issuance
As noted earlier, the U of M is the assignee of the ‘350 Patent. The inventors are

identified as William Alan C. Mutch and Gerald Robin Lefevre.11 The ‘350 Patent stems from
Application No. 404,464, filed on March 15, 1995.12 The patent issued on July 15, 1997.13

10

Doc. #84, p. 3 ¶ 8.

11

Doc. #1-1, p. 1.

12

Doc. #1-1, p.1.

13

Doc. #1-1, p. 1.

4

b. The Abstract and Field of the Invention
The Abstract of the ‘350 Patent briefly summarizes the invention as computer controlling
the flow of biological fluid to an organ so that the natural variation of the flow is simulated.14
The Abstract specifically describes control of a blood pump flow output during cardiopulmonary
bypass to mimic normal pulsatile blood flow from the heart and control of a ventilator output to
mimic normal breathing of healthy lungs.15
The Field of Invention, which follows, is only slightly more illuminating:
The present invention relates to medical life support systems, and, in particular, to
the control of cardiopulmonary bypass pumps for open heart surgery and mechanical
ventilators to lungs.16
c. Background to the Invention
The Background to the Invention provides some further context to the subject invention.
It explains that during cardiopulmonary bypass surgery, the heart is stopped and the blood which
normally returns to the right side of the heart passes through a pump and oxygenating system and
is returned to the aorta, thereby bypassing the heart and lungs.17 During the procedure, the flow
of blood is “essentially non-pulsatile with a low amplitude waveform having monotonous
regularity.”18 Consequences identified with conventional non-pulsatile cardiopulmonary bypass
include metabolic acidosis, interstitial fluid accumulation, elevated system vascular resistance,

14

Doc. #1-1, p. 1.

15

Id.

16

Doc. #1-1, p. 41, column 1.

17

Doc. #1-1, p. 41, column 1.

18

Id.

5

arteriovenous shunting and impair brain oxygenation.19 According to the Background, because
the monotonous regularity of pumping blood during cardiopulmonary bypass and a set tidal
volume and respiratory rate of a mechanical ventilator is “in contrast to the intrinsic
spontaneously variable rhythms of heart rate, blood pressure, and respiration” associated with a
normal functioning heart and lungs, the invention sought to improve the safety and reduce the
consequences of open heart surgery.20
d.

Summary of the Invention

The Summary of the Invention reiterates the purpose of the invention is to regulate the
control of flow of biological fluid to an organ in a manner “that closely mimics” natural
variation.21 The manner of controlling the biological fluid to the organ depends on the fluid and
the organ concerned.22 The Summary of the Invention sets forth a number of steps pertaining to
the invention: First, a pattern of instantaneous changes in the flow of a biological fluid to an
organ is generated.23 Next, a variable control parameter is generated for regulation of flow of the
biological fluid to the organ in accordance with the pattern.24 The last step is to control the flow
of the biological fluid to the organ according to the variable control parameter.25
The Summary of the Invention notes that the subject invention “is applicable not only to

19

Id.

20

Id.

21

Doc. #1-1, p. 41, column 2, lines 2-7.

22

Doc. #1-1, p. 41, column 2, lines 64-66.

23

Doc. #1-1, p. 41, column 2, lines13-15.

24

Doc. #1-1, p. 41, column 2, lines 32-34.

25

Doc. #1-1, p. 41, column 2, lines 58-60.

6

control of a cardiopulmonary bypass pump or a mechanical ventilator but also to any other
operation or device involving this control of a biological fluid to any organ.” 26 It includes, as
examples, utilizing the principles for intra aortic balloon counterpulsation, improving
hemodialysis, applying the principles during extracorporeal membrane oxygenation, using in
conjunction with right and left ventricular assist devices, and using in the perfusion of organs
prior to transplantation.
e.

Drawings

The drawings describing the invention include flow diagrams, graphs, profiles, line
charts, line chart comparisons, and block diagrams.27 They assist in explaining, for example, the
steps of operation for a cardiopulmonary pump, the typical plot of natural variation of systolic
blood pressure and respiratory rate, and a typical pump pulsation profile controlled in accordance
with the invention compared with a plot of natural variations in blood pressure.28 The drawings
do not provide guidance for the disputed term.
f.

Summary of Disclosure

The Summary of Disclosure, while a concise synopsis, does not shed additional light on
the subject invention. It provides:
the present invention provides computer control of the operation of a
cardiopulmonary bypass pump, a lung ventilator or other device which provides
simulation of in vivo variability of flow of a biologic fluid to an organ.29

26

Doc. #1-1, p. 42, column 3.

27

Doc. #1-1, pp. 2-40; pp. 42-43, columns 3 - 5.

28

Id.

29

Doc. #1-1, p. 47, column 14.

7

The Summary of Disclosure does not limit the subject invention to cardiopulmonary bypass
pumps or ventilators, noting “[m]odifications are possible within the scope of this invention.30
g.

Claims

The ‘350 Patent contains the following specific claims:
1.
A method of controlling flow of a biological fluid to an organ during
controlled life support conditions, said biological fluid being the primary source of
fluid to sustain life support to an organ, wherein said method which comprises:
establishing a predetermined pattern of variations over time of instantaneous
changes in flow of a biological fluid to an independently-functioning normal
organ of a mammalian species,
generating a variable control parameter for regulation of flow of said biological
fluid to an organ during controlled life support conditions in accordance with
said predetermined pattern, and
controlling said flow of said biological fluid to said organ during controlled life
support conditions in accordance with said variable control parameter to
provide a variable flow of said biological fluid to the organ during controlled
life support conditions which mimics the normal flow of said biological fluid
to a normal organ.
2.
A method of controlling flow of ventilating gas from a ventilator device to
the lungs of a body during controlled life support conditions, said biological fluid
being the primary source of fluid to sustain life support to an organ, wherein said
method comprises:
established a predetermined pattern of variation over time of instantaneous
respiratory rate and tidal volume of the independently-functioning normal
lungs of a mammalian species,
generating a signal corresponding in value to an individually-determined
respiratory rate and tidal volume in said predetermined pattern,
generating a control voltage corresponding in magnitude to said signal,
applying said control voltage to said ventilator device to provide an output of
ventilating gas from said ventilating device of a respiratory rate proportional
to the magnitude of said signal, and
repeating said steps of generating a signal, generating a control voltage and
applying said control voltage to said ventilator device for each next
individually-determined respiratory rate of said predetermined pattern, to
provide a variable flow of ventilating gas from the ventilator device to the
lungs of the body under controlled life support conditions which mimics

30

Id.

8

normal breathing of healthy lungs.
3.
Apparatus for controlling the flow of biological fluid to an organ, said
biological fluid being the primary source of fluid to sustain life support to an organ,
wherein said method comprises:
means for establishing a predetermined pattern of variations over time of
instantaneous changes in flow of a biological fluid to an independentlyfunctioning normal organ of a mammalian species,
means for generating a variable control parameter for regulation of flow of the
biological fluid to an organ during controlled life support conditions in
accordance with the predetermined pattern, and
means for controlling the flow of the biological fluid to the organ during
controlled life support conditions in accordance with the variable control
parameter to provide a variable flow of said biological fluid to the organ
during controlled life support conditions which mimics the normal flow of
said biological fluid to a normal organ.31
h.

Disputed Constructions

The parties propose divergent claim constructions for the term “controlled life support
conditions.” The U of M contends that “controlled life support conditions” includes conditions
in which a medical life support system is the primary, not necessarily sole, source of biological
fluid to an organ. Draeger counters that “controlled life support conditions” as used in the
subject invention must be interpreted to mean there is no patient breathing effort. Draeger urges
that the term “primary source” pertains to the biological fluid and it has no “logical or technical
connection” to “controlled life support conditions.”32
DISCUSSION
1.

Claim Construction Principles
Patent claim construction – the interpretation of the patent claims that define the scope of

31

Doc. #1-1, columns 249 & 250.

32

Doc. #75, p. 18.

9

the patent – is a matter of law for the court.33 “[T]he claims of a patent define the invention to
which the patentee is entitled the right to exclude.” 34 Claim construction requires an
examination of the intrinsic evidence of record, including the claims of the patent language, the
specification, and the prosecution history.35 The starting point for claim construction is a review
of the words of the claims themselves. The terms used in the patent are presumed to carry “the
meaning that the term would have to a person of ordinary skill in the art at the time of the
invention.36 Because the meaning of a claim term as understood by persons of skill in the art is
often not immediately apparent, a court may look to the sources available to the public that show
what a person of skill in the art would have understood the claim language to mean.37A court may
use a dictionary to “assist in understanding the commonly understood meaning” of a term, so
long as any meaning found in such sources does not contradict the definition that is found in the
patent documents.38 In other words, a court must ensure that any reliance on dictionaries accords
with the intrinsic evidence: the claims themselves, the specification, and the prosecution
history.39
Second, a court considers the entire specification to define technical terms that might not

33

Markman v. Westview Instruments, Inc., 52 F.3d 967, 970-71 (Fed. Cir. 1995), aff’d, 517 U.S. 370

(1996).
34

Phillips v. AWH Corp., 415 F.3d 1303, 1313 (Fed. Cir. 2005) (quoting Innova/Pure Water, Inc. v. Safari
Water Filtration Systems, Inc., 381 F.3d 1111,1115 (Fed. Cir. 2004)).
35

Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed. Cir. 1996).

36

Phillips, 415 F.3d at 1313.

37

Id. at 1314.

38

Id. at 1322-23.

39

Id. at 1314.

10

lend themselves to an ordinary meaning. The specification is “the single best guide to the
meaning of a disputed term.” 40 The specification may prescribe a special definition given to a
claim term, or a disavowal of a claim scope by the inventor.41 In such cases, the inventor’s
intention that is expressed in the specification is dispositive.42 A court may not, however, import
limitations from the specification into the claims.43 To avoid importing limitations from the
specification into the claims, a court considers that the purposes of the specification are to teach
and enable those of skill in the art to make and use the invention and to provide a best mode for
doing so.44
Third, intrinsic evidence also includes the patent’s prosecution history, which contains
evidence of the United States Patent and Trademark Office (hereafter “PTO”) and the inventor’s
understanding of the patent.45 The prosecution history includes the record of the proceedings
before the PTO and any prior art cited by the applicant.46 Because the prosecution history lacks
the clarity of the specification, it is less useful.47 Nevertheless, an explicit statement made by an
applicant during the patent’s prosecution may serve to narrow the scope of the claim.48 “The

40

Id. at 1315.

41

Id. at 1316.

42

Id.

43

Id. at 1323.

44

Id.

45

Id. at 1317.

46

Id.

47

Id.

48

Spectrum Int’l v. Sterilite Corp., 164 F.3d 1372, 1378-79 (Fed. Cir. 1988).

11

purpose of consulting the prosecution history in construing a claim is to ‘exclude any
interpretation that was disclaimed during prosecution.’” 49
If after an examination of the intrinsic evidence the court finds the claim ambiguous, the
court may look to extrinsic evidence, including expert and inventor opinions, treatises, and
articles.50 Courts are to look to extrinsic evidence as a last resort, as it is less reliable than
intrinsic evidence.51 In addition, extrinsic evidence must be considered in the context of intrinsic
evidence.52
2.

Other Canons of Claim Construction
Apart from the evidence upon which claim construction may be based, claim construction

involves various “canons.” One canon of claim construction is that “claim terms are presumed to
be used consistently throughout the patent, such that the usage of a term in one claim can often
illuminate the meaning of the same term in other claims.” 53 It follows then that “[w]hen
different words or phrases are used in separate claims, a difference in meaning is presumed.”54
Likewise, a court must interpret claims so that no term becomes “superfluous.” 55

49

Research Plastics, Inc. v. Federal Packaging Corp., 421 F.3d 1290, 1296 (Fed. Cir. 2005) (quoting
Rhodia Chimie v. PPG Indus., 402 F.3d 1371, 1384 (Fed. Cir. 2005)).
50

Phillips, 415 F.3d at 1317.

51

Id. at 1317-18.

52

Id. at 1318-19; Network Commerce, Inc. v. Microsoft Corp., 422 F.3d 1353, 1361 (Fed. Cir. 2005).

53

Research Plastics, Inc., 421 F.3d at 1295.

54
Nystrom v. TREX Co., Inc., 424 F.3d 1136, 1143 (Fed. Cir. 2005) (citing Tandon Corp. v. United States
Int’l Trade Comm’n, 831 F.3d 1017, 1023 (Fed. Cir. 1987)).
55

See Merck & Co. v. Teva Pharms. USA, Inc., 395 F.3d 1364, 2372 (Fed. Cir. 2005) (“A claim
construction that gives meaning to all the terms of the claim is preferred over one that does not do so.”).

12

Another canon of claim construction is that the patentee may act as “lexicographer.” In
other words, “the specification may reveal a special definition given to a claim term by the
patentee that differs from the meaning it would otherwise possess,” and when that happens, the
patentee’s definition must govern.56 The authority of the specification as a source for definitions
for claim terms, however, is not limitless. A court must take care not to import a limitation from
the written description; instead, it must use the written description for enlightenment.57
3.

The Court’s Independent Obligation to Construe Terms
The Federal Circuit Court of Appeals has expressly held that a court is free to adopt a

construction independent of those suggested by the parties.58 Accordingly, the Court has an
obligation to construe the patent terms independently, apply the Phillips methodology, and is not
bound to adopt either party’s proffered construction of any claim terms.
With these principles in mind, the Court turns to construction of the disputed claim terms
of the ‘350 Patent.
4.

The ‘350 Patent
The Court first looks to the words of the claims, giving them the plain meaning for a

person of ordinary skill in the art in question at the time of the invention. Three claims are
contained in the ‘350 Patent. Each claim contains the disputed term “controlled life support
conditions”. Draeger contends that “controlled life support conditions” is limited to situations
where there is no patient breathing effort. The U of M counters that Draeger’s construction
56

Phillips, 415 F.3d at 1316.

57

Playtex Prods, Inc. v. Proctor & Gamble Co., 400 F.3d 901, 906 (Fed. Cir. 2005) (citing Comark
Communications v. Harris Corp., 156 F.3d 1182, 1186-87 (Fed. Cir. 1998)).
58

Exxon Chem. Patents, Inc. v. Lubrizol Corp., 64 F.3d 1553, 1555 (Fed. Cir. 1995).

13

improperly limits the scope of the invention such that the patent-in-suit applies where biological
fluid is the primary source of fluid, and not necessarily the sole source, to sustain life support to
an organ.
a.

Claim Terms and Specification

In the first amendment, the patentee added the term “controlled life support conditions.”
This term is not defined, described, or found anywhere else in the specification of the patent.
There is no evidence in the record from which this Court can conclude the term has an ordinary
meaning to those skilled in the field. The claim language, itself, does not resolve the parties’
dispute. It is, however, arguable whether controlled life support conditions is limited to those
situations where there is no patient breathing effort.
The plain language of the claims suggest that the biological fluid must be the primary
source of fluid to sustain life to the organ. Looking to the specification, the U of M correctly
points out that the background section references healthy patients being ventilated during elective
surgery.59 Such a scenario may very well encompass situations where there is some patient
breathing effort. Likewise, the background also notes that prevention of alterations in respiratory
function would represent “a major advance in management of all patients requiring ventilatory
support.”60 Thus, at first blush, the scope of the invention appears to encompass a variety of
patient conditions, ranging from situations where there is some patient breathing effort to no
patient breathing effort. Nonetheless, the U of M’s proposed construction falls apart after the
prosecution history is considered.

59

Doc. #1-2, p. 41, column 1, lines 48-49.

60

Id. at p. 41, column 1, lines 51-53.

14

b.

Detailed Prosecution History

When a patentee unequivocally disavows a certain meaning to the patent, the doctrine of
prosecution disclaimer attaches and narrows the ordinary meaning of the claim.61 The patent-insuit, Application Number 404,464 filed on March 15, 1995, identified four claims. Claim 2 was
withdrawn from consideration.62 Upon review by the PTO, the Examiner rejected Claims 1, 3,
and 4 on the basis that they were unpatentable because of a prior art patent - U.S. 4,448,192
(Stawitcke).63 Post-Markman hearing, the Court has restudied the Stawitcke patent in light of
the U of M’s arguments. Stawitcke involves a ventilator that accommodates a patient’s breathing
efforts through the use of a “novel control law.”64 The identified novel pressure-volume control
law determines a target ideal pressure-volume wave-form, which is then modified during the
ventilator operation to enable the patient to breathe with minimum ventilation opposition or
fighting.65 Stawitcke improved the prior art by regulating pressure as a function of volume
during inhalation and exhalation instead of controlling the pressure or flow as a function of
time.66 In other words, Stawitcke describes a ventilator adapting to patient activity to ensure the
target ventilation is reached through the delivery of a target volume.
During prosecution of the patent-in-suit, the patentee differentiated the prior art:

61

Shire Development, LLC v. Watson Pharmaceuticals, Inc., - - F.3d - -, 2014 WL 1258136, *4 (Fed. Cir.
2014) (quoting Omega Eng’g, Inc. v. Raytek Corp., 334 F.3d 1314, 1324 (Fed. Cir. 2003)).
62

Doc. #74-5 (First Office Action).

63

Id.

64

Doc. #74-3, p. 2 of 20, Abstract.

65

Id.

66

Id. at p. 13 of 20, column 4, lines 5-11.

15

The Stawitcke devices as relied on by the Examiner is concerned primarily
with the weaning type of ventilator which provides assisted ventilation to a patient
rather than the present invention which is concerned with ventilation during
controlled life support conditions. . . . Th[e] [Stawitcke] system provides for a
variable degree of assistance, depending on the degree of patient effort and provides
the assisted ventilation in accordance with the described pressure-volume law, the
parameter of which can be changed in response to measurements and calculations
relating to parameters, such as compliance and resistance.67
***
. . .What is described in Stawitcke in Col. 5 is how the system accommodates patient
effort while still maintaining the required target volume and the point at which the
positive pressure control law takes over. . . . The passage in Col. 7 to which the
Examiner refers simply indicates that the target pressure is preset by the clinician and
the pressure-volume wave form required for the particular patient is constantly
computed and applied. In the present invention, there is no patient effort to be taken
into consideration and the variation in respiratory rate and tidal volume is
predetermined from a pattern taken from a healthy mammal.68
It is clear, therefore, that the Stawitcke reference is concerned with quite
different circumstances from the present invention. As already noted, the Stawitcke
reference is concerned primarily with the weaning type of ventilator wherein gas flow
to the patient is controlled in accordance with a pressure-volume control law to
ensure the delivery of a target volume to the weaning patient while taking into
account patient effort. In the absence of patient effort, the system described by
Stawitcke will deliver a monotonously regular tidal volume and respiratory rate
according to the preset values programmed by the operator.69
In contrast, in the present invention, the ventilator is operating during
controlled life support conditions where there is no patient effort to be taken into
consideration. Rather than provide a monotonous flow of gas to the patient, a
variable flow is provided in accordance with a predetermined pattern of instantaneous
respiratory rate and tidal volume which is established from the healthy lungs of a
mammal . . .70
The patentee made plain in its first amendment that Stawitcke involved a ventilator

67

Doc. #74-6, p. 5 of 8 (First Amendment).

68

Id. at p. 7 of 8.

69

Id.

70

Id. at pp. 7-8 of 8.

16

operating under weaning conditions where there is some patient breathing effort and the subject
invention pertained to a ventilator operating during controlled life support conditions where there
is no patient breathing effort to be taken into consideration. Accordingly, Claim 1 of the subject
invention, which was initially identified, in part, as “[a] method of controlling flow of a
biological fluid to an organ”, was amended to read, in part, “[a] method of controlling flow of a
biological fluid to an organ during controlled life support conditions . . .” 71 Similarly, Claim 3
initially identified, in part, as “[a] method of controlling flow of ventilating gas from a ventilator
device to the lungs of a body” was amended to read, in part, “[a] method of controlling flow of
ventilating gas from a ventilator device to the lungs of a body during controlled life support
conditions . . .”.72
On March 18, 1996, the PTO, again, rejected all claims. This time the Examiner found
the claims in the subject invention were unpatentable over U.S. 4,584,996 (Blum).73 The
Examiner explained that Blum discloses a method for gathering “normal” breathing data to be
applied subsequently to match “normal” demand, and although there is no mention of “controlled
life support conditions”, the method applies to a variety of patient care settings, which “would
have been obvious to one having ordinary skill in the art.”74
The patentee submitted amendments to the claims. This time the method set forth in
Claim 1 read as follows: controlling biological fluid to an organ during controlled life support

71

Id. at p. 2 of 8 (emphasis in original).

72

Id.

73

Doc. #74-7 (Second Office Action).

74

Id. at pp. 2-3 of 8.

17

conditions in accordance with the variable control parameter “to provide a variable flow of said
biological fluid to the organ during controlled life support conditions which mimics the normal
flow of said biological fluid to a normal organ.” 75 The patentee re-explained that the purpose of
the invention was “to provide a pattern of flow of the biological fluid to the organ which mimics
normal flow to a healthy organ.” 76 The patentee described the invention under consideration as
“a mechanical ventilator which in a controlled life support scenario, wholly controls the flow of
ventilating gas to the lungs of the patient under life support.”77
Additionally, the patentee distinguished the environment in which Blum’s procedure may
be employed.78 The patentee asserted that Blum applies to the specific condition of providing
oxygen therapy for a C.O.L.D. [chronic obstructive lung disease] patient by providing
supplemental oxygen while not otherwise altering the pressure relationships within the
respiratory tract or the volume of the gas inhaled.79 In other words, there is no determination in
Blum made with respect to a “normal independently functioning organ.”80 Instead, according to
the patentee, the Blum patent provides for a single determination of respiratory rate and that rate
is used in combination with the oxygen level determination; therefore, the only “pattern” that
exists is a continuous flow of supplemental oxygen during the inspiratory phase during

75

Doc. #74-8 (Second Amendment).

76

Id. at p. 5 of 11.

77

Id.

78

Id. at p. 5 of 11.

79

Id. at p. 6 of 11.

80

Id. at p. 7 of 11.

18

predetermined on-cycles and ceasing that flow during a predetermined number of off-cycles.81
The Examiner interviewed the applicant on September 20, 1996.82 The Examiner noted
that there was an agreement to amend the claims “to have the biological fluid as the primary
source of fluid to sustain life.”83 He also noted the distinction regarding prior art: “Blum teaches
oxygen biological fluid as a secondary source.”84 He further concluded that the claims would be
allowed with the amendment.85 A Notice of Allowability was issued on February 3, 1997.86 The
Examiner’s amendment provided that Claim 2 had been cancelled and Claims 1, 3, and 4
contained the following additional language: “said biological fluid being the primary source of
fluid to sustain life support to an organ, wherein said method - -.”87
c.

Brief Summary of Claim Progression

For purposes of the construction of the disputed term, Claim 1 is exemplary of the three
claims contained in the ‘350 Patent. The following summary compares the changes with regard
to Claim 1 as initially proposed and as ultimately allowed:

81

Id.

82

Doc. #74-9 (Examiner Interview Summary Record).

83

Id.

84

Id.

85

Id.

86

Doc. #74-10 p. 2 of 6.

87

Id. at p. 3 of 6.

19

As Filed on 3/15/1995

1st Office Action
Response 2/15/1996

2nd Office Action
Response 7/2/1996

Claims as Allowed on
2/3/1997

A method of controlling
flow of a biological fluid
to an organ, which
comprises:

A method of controlling
flow of a biological fluid
to an organ during
controlled life support
conditions, which
comprises:

A method of controlling
flow of a biological fluid
to an organ during
controlled life support
conditions, which
comprises:

A method of controlling
flow of a biological fluid
to an organ during
controlled life support
conditions, said
biological fluid being the
primary source of fluid to
sustain life support to an
organ, wherein said
method which comprises:

establishing a pattern of
variations over time of
instantaneous changes
in flow of a biological
fluid to an organ of a
mammalian species,

establishing a
predetermined pattern
of variations over time
of instantaneous
changes in flow of a
biological fluid to
independentlyfunctioning normal [an]
organ of a mammalian
species,

establishing a
predetermined pattern
of variations over time
of instantaneous
changes in flow of a
biological fluid to an
independentlyfunctioning normal
organ of a mammalian
species,

establishing a
predetermined pattern
of variations over time
of instantaneous
changes in flow of a
biological fluid to an
independentlyfunctioning normal
organ of a mammalian
species,

generating a variable
control parameter for
regulation of flow of
said biological fluid to
an organ in accordance
with said pattern, and

generating a variable
control parameter for
regulation of flow of
said biological fluid to
an organ during
controlled life support
conditions in
accordance with said
predetermined pattern,
and

generating a variable
control parameter for
regulation of flow of
said biological fluid to
an organ during
controlled life support
conditions in
accordance with said
predetermined pattern,
and

generating a variable
control parameter for
regulation of flow of
said biological fluid to
an organ during
controlled life support
conditions in
accordance with said
predetermined
pattern, and

controlling said flow of
said biological fluid to
said organ in
accordance with said
variable control
parameter.

controlling said flow of
said biological fluid to
said organ during
controlled life support
conditions in
accordance with said
variable control
parameter.

controlling said flow of
said biological fluid to
said organ during
controlled life support
conditions in
accordance with said
variable control
parameter to provide a
variable flow of said
biological fluid to the
organ during controlled
life support conditions
which mimics the
normal flow of said
biological fluid to a
normal organ.

controlling said flow of
said biological fluid to
said organ during
controlled life support
conditions in
accordance with said
variable control
parameter to provide a
variable flow of said
biological fluid to the
organ during controlled
life support conditions
which mimics the
normal flow of said
biological fluid to a
normal organ.

20

The focus of the parties’ dispute is on whether the term “primary source” of the biological
fluid modifies controlled life support conditions or simply differentiates the subject invention
from other inventions providing secondary or supplemental biological fluid, i.e. oxygen. The
Court tentatively determined that the prosecution history demonstrates that the term “controlled
life support conditions” focuses on the patient’s condition. In light of the U of M’s arguments at
the Markman hearing to the contrary, the Court has re-examined the Stawitcke patent and the
entire prosecution history. Upon re-examination, the Court finds the U of M’s arguments
unpersuasive.
In distinguishing the subject invention from Stawitcke, the patentee described the subject
invention as one operating where there is “no patient effort to be taken into consideration.” The
patentee noted this distinction two separate times in the first amendment. The patentee also
explained more than once that the subject invention was not similar to a weaning-type of
ventilator that considers patient effort such as Stawitcke. These repeated statements made by the
patentee constitute an unambiguous disavowal of the scope of the subject invention. The term
“controlled life support conditions” as used in the subject invention pertains to situations where
there is no patient breathing effort taken into consideration.
The U of M’s arguments, which broaden the meaning of controlled life support
conditions, focus on a second distinction made in response to the Examiner’s rejection of the
application over prior art. In a later amendment, the patentee explained that the biological fluid
being provided to the patient in the subject invention was the primary rather than secondary or
supplemental source of biological fluid (Blum). The term “primary source of fluid” was added at
the end of the prosecution by the patentee in order to distinguish the subject invention from, for

21

example, a nasal cannula providing supplemental oxygen (Blum). In Blum, the flow rate of
oxygen is constant. Variation in the system is tied to the number of on and off cycles to reach a
specific predetermined level. There is no system in Blum that attempts to mimic the normal flow
of biological fluid during controlled life support conditions. In light of the distinction being
made by the patentee in response to the Examiner’s reliance on Blum, there is no indication that
the patentee’s addition of the term “primary source of fluid” had anything to do with the meaning
of “controlled life support conditions” previously claimed by the patentee to the Examiner. The
U of M asks this Court to infer that the term “primary source” broadens the parameters of
“controlled life support conditions” after the patentee had expressly claimed otherwise. It does
not follow that the latter statements made to distinguish Blum control and the preceding
statements made to distinguish Stawitcke are to be ignored. The U of M’s proposed construction
attempts to recapture through claim interpretation specific meanings disclaimed during
prosecution.
A review of the intrinsic evidence as a whole reveals that the patent-in-suit applies during
“controlled life support conditions” where no patient breathing effort is taken into consideration
and the biological fluid needed to sustain life is the primary source of fluid, as opposed to a
secondary or supplemental source. The U of M specifically disclaimed that its patent covers
medical situations in which there is a patient under controlled life support conditions and the
patient’s breathing effort is to be taken into consideration.
d.

Extrinsic Evidence

While courts may consider extrinsic evidence to educate themselves about the patent and
technology at issue, it is improper to rely on extrinsic evidence in construing claims unless, after

22

consideration of all the intrinsic evidence, ambiguity remains.88 Finding no ambiguity in the
intrinsic evidence, the Court will not consider any extrinsic evidence.
CONCLUSION
The claim term in dispute, the parties’ proffered construction, and the Court’s own
construction are summarized as follows:
Claim Term

U of M’s
Construction

Draeger’s
Construction

Court’s
Construction

controlled life
support
conditions

any patient
condition so long
as the biological
fluid is the primary
source to sustain
life support to an
organ

only patient conditions
where there is no
breathing effort

only patient
conditions where there
is no patient effort to
be taken into
consideration

The Court hereby adopts the foregoing as its final construction of the patent claim terms
in dispute.
IT IS SO ORDERED.
Dated this 16th day of June, 2014.

/s/ Ralph R. Erickson
Ralph R. Erickson, Chief Judge
United States District Court

88

Mantech Envtl. Corp. v. Hudson Envtl. Servs., Inc., 152 F.3d 1368, 1373 (Fed. Cir. 1998).

23