Searching over 5,500,000 cases.


searching
Buy This Entire Record For $7.95

Download the entire decision to receive the complete text, official citation,
docket number, dissents and concurrences, and footnotes for this case.

Learn more about what you receive with purchase of this case.

SUNRISE MEDICAL HHG, INC. v. AIRSEP CORP.

April 25, 2000

SUNRISE MEDICAL HHG, INC., PLAINTIFF,
V.
AIRSEP CORPORATION, DEFENDANT.



The opinion of the court was delivered by: D. Brooks Smith, District Judge.

AMENDED FINDINGS OF FACT WITH CONCLUSIONS OF LAW

TABLE OF CONTENTS

I. AMENDED FINDINGS OF FACT 355 A. The Parties 355 B. The Patents In Suit 356 1. The Claims 356 a. The `303 Patent 356 b. The `224 Patent 357 2. The Specifications 359 a. The `303 Patent 359 b. The `224 Patent 362 3. The Prosecution History of the `303 Patent 364 C. Sunrise's Entry Into the OCD Market 367 D. AirSep's Development of the ImPulse Select 368 E. The Witnesses 370 F. Likelihood of success on the merits 371 1. Ownership 371 2. Infringement 373 a. The `303 Patent 373 i. Whether AirSep's ImPulse Select "Employed a Method" in Violation of the `303 Patent 373 ii. Alleged Non-infringement of Invacare Venture Device 373 iii. Non-infringement Defense of Providing a Dose During Exhalation 374 (A.) Claim Construction Testimony 374 (B.) The Accused Device Can Provide a Dose of Oxygen during Exhalation 374 (C.) The FDA Investigation 376 iv. Equivalence of Fluidic Control Versus Electronic Control 377 v. Whether the Sequence of Steps of the ImPulse Select Matches the Sequence of Steps Required by the `303 Patent 379 vi. Does the Accused Device Meet the "At Least As Great A Rise" Limitation of Claim 3? 380 vii. AirSep's Non-Infringement Opinion Regarding the `303 Patent 381 viii. Has Any Other Person Used the ImPulse Select in Violation of the `303 Patent? 381 ix. Did AirSep Intend Any Entity to Use the ImPulse Select in Violation of That Patent? 381 b. The `224 Patent 381 i. AirSep's Development of the ImPulse and ImPulse Select 381 ii. Structure and Operation of the ImPulse Select 381 iii. The Evolution of the Bypass Valve 385 iv. Definition of Bypass Valve 388 v. Claim Construction Testimony 389 vi. The ImPulse Select's Bypass Valve 389 vii. AirSep's Patents and Patent Applications 390 viii. AirSep's Testing of the EX 2000. 391 ix. The Bench Study Article and Comparison of the EX 2000 to the ImPulse Select 392 x. Sunrise's Testing of the Accused Device to Determine Infringement 393
 
3. Validity 394 a. The `303 Patent 394 i. The Disclaimer 394 ii. One of Ordinary Skill in the Art 394 iii. The Combination of U.S. Patent No. 2,766,752 (Meidenbaur) and Smith Reference 394 b. The `224 Patent 401 i. One of Ordinary Skill in the Art 401 ii. The OMS 20/50 Reference (Claim 1) 402 iii. The Combination of OMS 20/50 Reference and the European Patent (Claims 2-6) 406 iv. The Combination of the `627 Patent, the `881 Patent and the European Patent 408 v. Other Indicia of Obviousness 413 c. Sunrise's Patent Search — EX 2000 413 4. Enforceability 413 a. Patent Misuse — The Puritan Bennett License — The `303 Patent 413 b. Inequitable Conduct — The `224 Patent 414 5. Prior Adjudication/Reissue and Reexamination 416 G. Irreparable Harm 416 1. Sunrise's Allegations of Lost Market Share and Price Reduction 416 a. Alleged Price Reduction 416 b. Alleged Reduction in Market Share 425 2. Sunrise's Reputation and Goodwill 426 3. Sunrise's Patent Policies 426 4. The Annual Report 426 5. Market Life of Sunrise's Products 427 6. Sunrise's Delay in Bringing the Action 427 7. Sunrise's Lost Profits 428 8. Non-Commercialization of the `303 Patent 430 9. AirSep's Ability to Meet a Judgment 431 H. Balance of Hardships 431 I. False Patent Marking 434 CONCLUSIONS OF LAW II. JURISDICTION AND VENUE 434 III. STANDARDS FOR ISSUING A PRELIMINARY INJUNCTION 434 IV. LIKELIHOOD OF SUCCESS ON THE MERITS 436 A. Ownership 436 B. Infringement 437 1. Claim Construction Principles 437 a. General Precepts 437 b. Means-Plus-Function Claims 439 2. Infringement Principles 440 a. Literal Infringement 441 b. Doctrine of Equivalents 441 c. Prosecution History Estoppel 442 3. Comparison of the `303 Patent Claims to the Accused Method 443 a. Does AirSep Directly Infringe Claim 3 of the `303 Patent Under 35 U.S.C. § 271 (a)? 443 b. Is There Direct Infringement of Claim 3 by Others? 443 i. Literal Infringement 443 ii. Prosecution History Estoppel and Infringement of Claim 3 Under The Doctrine Of Equivalents. 446 c. Whether AirSep Intentionally Induced Direct Infringement of Claim 3 448 4. Comparison of the `224 Patent Claims to the Accused Device 448 a. Literal Infringement 448 b. Doctrine of Equivalents 448 C. Validity 450
 
1. 35 U.S.C. § 102 — Anticipation 451 2. 35 U.S.C. § 103 — Obviousness 451 3. Scope and Content of the Prior Art 452 4. Level of Ordinary Skill in the Art 453 5. The Lack of Differences Between the Claims and the Prior Art 453 a. Whether Claims 3-5 of the `303 Patent are Invalid Under § 103 as Obvious 453 i. Sunrise's Alleged Admission of Invalidity 453 ii. Whether Claims 3-5 are Obvious in View of the `752 Patent (Meidenbaur) over Smith 454 b. Whether the Claims of the `224 Patent are Invalid 455 i. Whether Claims 1-6 of the `224 Patent are Invalid on the Ground of Anticipation 455 ii. Whether the Remaining Claims of the `224 Patent are Invalid Under 35 U.S.C. § 103 in View of the OMS 50 Reference Over the European Patent 456 iii. Whether Claims 1-7 of the `224 Patent are Invalid Under 35 U.S.C. § 103 in View of the `627 Patent over the OMS 50, the `881 Patent or the European Patent 457 6. Secondary Considerations of Nonobviousness 457 D. Enforceability 457 1. Whether Sunrise Misused the `303 Patent 457 2. Whether There Was Inequitable Conduct During the Prosecution of the `224 Patent 457 V. IRREPARABLE HARM 461 VI. THE BALANCE OF THE HARDSHIPS 463 VII. WHETHER PUBLIC POLICY SUPPORTS THE GRANT OF AN INJUNCTION 464 VIII. CONCLUSION and ORDER 465

On February 7-11, 2000, I held a preliminary injunction hearing in the above-captioned patent infringement case, issuing findings of fact on April 7, dkt. no. 84. Pursuant to the court's order contained therein, the parties have filed exceptions to those findings. The following memorandum constitutes my amended findings of fact with conclusions of law pursuant to Fed. R. Civ. P. 52(a). For the following reasons, I will deny plaintiff's motion for preliminary injunction.

I. AMENDED FINDINGS OF FACT

A. The Parties

Plaintiff, Sunrise Medical HHG Inc. ("Sunrise"), is a California corporation having a principal place of business for its Respiratory Products Division (also known as Sunrise DeVilbiss) at 100 DeVilbiss Drive, Somerset, Pennsylvania 15501-0635.*fn1 It is a subsidiary of a publicly traded company.*fn2 AirSep Corporation, the defendant in this action, is a New York corporation having a principal place of business at 290 Creekside Drive, Amherst, New York 14228.*fn3

Sunrise has asserted infringement of Claims 1 through 7 of U.S. Patent Number 5,755,224 ("the `224 patent") and Claims 3 through 5 of U.S. Patent Number 4,457,303 ("the `303 patent") under 35 U.S.C. § 271(a) and accuses AirSep of directly infringing, contributorily infringing and inducing activities which would constitute the infringement of the `224 Patent and the `303 Patent.*fn4 The accused device is an electronic oxygen conserving device ("OCD") that provides convenience and mobility to respiratory patients with therapeutic oxygen needs, and which is marketed by AirSep as its ImPulse Select product. The need for such supplemental oxygen delivery methods has existed since at least as early as 1967.*fn5

B. The Patents In Suit

1. The Claims

a. The `303 Patent

Sunrise claims to be the owner of the `303 patent, which was issued July 3, 1984 upon the application of Dr. Gerald Durkan and entitled "Respirating Gas Supply Control Method and Apparatus Therefore."*fn6 The `303 patent discloses and claims a method of supplying supplemental dosages of a respirating gas, such as oxygen, to a patient having an inspiration period and expiration period for every breath. The initiation of the inspiration period is sensed and a timing means is used to predetermine the duration T1 of the dose of respirating gas. The duration of T1 is less than the duration of inspiration period T2.*fn7 The dose is supplied immediately in response to the sensed inspiration. The dose is supplied for the duration T1 at a rate R1 which is set to provide at least as great a rise in the partial pressure of the respirating gas in the blood as the continuous application of said gas at a lower rate R2 for the full duration of the inspiration period T2. Put more simply, it is a method of providing oxygen at a high flow rate during the beginning of the patient's inspiration in such a manner as to oxygenate the patient's blood at least as well as continuously supplying oxygen at a lower, conventional rate throughout the patient's entire inspiration.*fn8

One advantage of this invention is that it provides an economical and efficient method of delivery which allows for the conservation of oxygen.*fn9 The use of a timer to predetermine the period of the dose provides another significant advantage, enabling the volume of the pulse to be substantially constant from one breath to another, even as the respiration rate varies.*fn10

As acknowledged in the `303 patent, intermittent demand oxygen flow had been tried in the past,*fn11 but prior intermittent demand oxygen devices supplied oxygen for the full inspiration period*fn12 and some prior demand oxygen devices supplied oxygen that, although commencing with a surge in the pattern of flow at the start of inspiration, still supplied oxygen during the entire inspiration period.*fn13

The `303 patent contains eight claims, three of which are independent (Claims 1, 2, and 3) and five of which are dependent claims (Claims 4-8). Claims 1 and 2 of the `303 patent are apparatus claims, while Claims 3-8 are directed to a method of supplying dosages of oxygen to a person.*fn14 Sunrise does not contend that AirSep is directly or indirectly infringing independent Claims 1 or 2 of the `303 patent.*fn15

Claim 3 of the `303 Patent reads:

A method of supplying supplemental dosages of respirating gas to a spontaneously breathing in vivo respiratory system having an inspiration period and an expiration period, said inspiration period being of duration T2 during which period a negative pressure relative to ambient pressure exists in said in vivo respiratory system at the location whereat respirating gas is introduced to said system, said expiration period comprising a positive pressure relative to ambient pressure existing in said in vivo respiratory system at the location whereat respirating gas is introduced to said system, said method comprising the steps of:

(1) sensing initiation of said inspiration period;

(2) using timing means to predetermine a duration T1 for which a dose of respirating gas is to be supplied to said in vivo respiratory system, said duration T1 being less than the duration T2 of negative pressure relative to ambient pressure occurring in said in vivo respiratory system during said inspiration period; and,
(3) supplying immediately in response to said sensed inspiration a dose of respirating gas to said in vivo respiratory system, said dose being supplied only for the duration T1, said dose being supplied substantially at the beginning of said sensed inspiration, said dose of gas being supplied at a rate R1, said rate R1 being set at a value such that it produces at least as great a rise in the partial pressure of said gas in blood interfacing with said respiratory system as the continuous application of said gas at a lower rate R2 for the duration T2; and,
automatically repeating steps (1), (2), and (3) for a plurality of consecutive inspiration periods.

Claim 4 of the `303 Patent reads:

The method of Claim 3, wherein T1 is less than 0.25 X T2.

Claim 5 of the `303 Patent reads:

The method of Claim 3, wherein T1 is less than 0.5 second.

b. The `224 Patent

Sunrise also claims to be the owner of the `224 patent issued May 26, 1998 and entitled "Cylinder-Mounted Oxygen Management Device." This patent was applied for by Gregory W. Good, Richard L. Dalton, Jr. and Jon Peter Gilchrist.*fn16 The `224 patent discloses and claims an oxygen management device adapted to be mounted on a post on a compressed gas cylinder for the purpose of providing a controlled flow of oxygen to a patient. The device comprises a manifold block having an opening to receive the post. The manifold block has a regulator, an over-pressure relief valve, a solenoid-operated flow control valve, and a bypass valve mounted on the manifold block and connected with internal passageways so that no tubing or tubing connectors are used.*fn17 The `224 patent contains one independent apparatus claim (Claim 1) and six apparatus claims that depend therefrom.

Claim 1 of the `224 Patent reads:

An oxygen management device adapted to be mounted on a post on a compressed oxygen cylinder for delivering a controlled flow of oxygen to a patient comprising:
a manifold block having an opening adapted to receive a post on an oxygen cylinder;
said manifold block opening having an oxygen connection adapted to engage and seal to a mating connection on an oxygen tank post;
means for securing said manifold block to an oxygen cylinder post received by said opening;
pressure regulating means on said manifold block for reducing the pressure of oxygen received from a cylinder to a predetermined low level;

an overpressure relief valve on said manifold block;

a solenoid operated flow control valve on said manifold block arranged for initiating and interrupting the delivery of oxygen from the cylinder to a patient;
a bypass valve on said manifold arranged in parallel with said solenoid operated flow control valve;
flow restricting means in series with said bypass valve to limit said oxygen flow through said bypass valve;
means for manually opening and closing said bypass valve; and,
control means responsive to inhalation by a patient for opening said solenoid operated flow control valve to deliver a dose of oxygen to a patient.

Claim 2 of the `224 Patent reads:

An oxygen management system, as set forth in claim 1, and further including an annular housing enclosing said manifold block, said pressure regulating means, said overpressure relief valve, said solenoid operated flow control valve, said bypass valve, said flow restrictor and said control means, and wherein said annular housing has an opening aligned with said manifold block opening and adapted to receive a post on an oxygen cylinder.

Claim 3 of the `224 Patent reads:

An oxygen management system, as set forth in claim 2, and further including an oxygen pressure gauge mounted on said manifold block and adapted to indicate the pressure oxygen in said manifold block from an oxygen cylinder.

Claim 4 of the `224 Patent reads:

An oxygen management system, as set forth in claim 2, and further including a knob extending from said housing for movement between first and second positions, and means for opening said bypass valve when said knob is in said first position and for closing said bypass valve when said knob is in said second position.

Claim 5 of the `224 Patent reads:

An oxygen management system, as set forth in claim 4, wherein said bypass valve has a valve stem movable between open and closed positions, and wherein said valve stem is moved by said opening and closing means to said open position when said knob is moved to said first position and to said closed position when said knob is moved to said second position.

Claim 6 of the `224 Patent reads:

An oxygen management system, as set forth in claim 2, and further including means on said housing for selecting and indicating the effective pulse flow rate delivered to an inhaling patient by said solenoid operated flow control valve.

Claim 7 of the `224 Patent reads:

An oxygen management system, as set forth in claim 1, and wherein said manifold block includes a plurality of oxygen passages connecting said pressure
regulating means, said overpressure relief valve, said solenoid operated flow control valve, said bypass valve, and said flow restricting means, and wherein said oxygen passages have a total volume of no greater than 0.1 cubic inch.

Claims 2 through 7 depend from Claim 1; thus, claims 2 through 7 incorporate each and every element of Claim 1 as if the limitations of Claim 1 were repeated within Claims 2 through 7.

2. The Specifications

a. The `303 Patent

The timing means of the `303 patent predetermines the duration of the pulse, T1, of the `303 Patent. The timing means includes a closed loop fluidic circuit 104 engaged with a power stream source 46 such that the power stream intersects the closed loop 104 at port 96c. When no negative pressure is being sensed, the power stream is vented to the atmosphere 96a.*fn18 As acknowledged in the `303 patent, fluidic logic elements have been used in prior intermittent demand oxygen systems.*fn19

Negative pressure in the cannula, which occurs only when a user is inhaling, is sensed by a pressure sensor. A first fluid signal, generated by means 64 on output leg 70, is applied to the second generating means 96 on line 102. If negative pressure is not sensed or ceases, then the fluid is cut off from the line 102. Line 102 is attached to the bottom portion of the closed loop 104a of second generating means 96.

The fluid separates along two paths. The first path pushes the power stream to divert the power stream from port 96a to outlet port 96b and thus to the valve line 100. The power stream flows along the valve line and actuates the valve 110 to an open position. The fluid flowing along the second path travels around the closed loop 104 with a variable orifice 106 and an elastomeric balloon 108 attached to the closed loop 104. The variable orifice 106 and elastomeric balloon 108 delay the fluid following along the second path for a predetermined period of time (T1) depending the size and capacities of the variable orifice and elastomeric balloon chosen. The sizes and capacities are chosen such that the time it takes the fluid to flow along the second path is much less than the inspiratory period of the patient. When the fluid following along the second path reaches the other side of the power stream, this fluid equalizes the power stream at port 96c by effectively pushing the power stream back so that it vents to the atmosphere through port 96a. This also has the effect of closing the fluidically operated demand valve and shutting off the supply of oxygen to the patient.

In the absence of negative pressure, that is, when inspiration ceases, there is no fluid traveling along the first path. Thus, the power stream is not pushed to outlet port 96b but reverts instead to port 96a and is vented to the atmosphere.*fn20 The absence of a fluid signal on output leg 70 of the generating means 64 results in suppression of the source means 98 (not pictured), which includes solenoid valve 110. Thus, no respirating gas is applied to the patient during expiration.*fn21

Nowhere in the patent specification is a method or apparatus described which is designed to or theoretically capable of delivering respirating gas to a patient during expiration. Moreover, the `303 patent specification draws a distinction between fluidic versus electronic circuits. At column 2, lines 24-30, the specification provides (emphasis added):

Of the prior art devices that attempt to detect apneic events, many, (including the devices disclosed in U.S. Pat. No. 3,357,428 to Carlson and 4,206,754 to Cox) periodically generate electrical (as opposed to fluidic) signals which are electrically monitored to determine when a patient has ceased to breathe satisfactorily and which activate an alarm as a warning indicator.

The structure for the timing means, as claimed in Claim 3, is described in the specification as follows:

The fluidic path 104 has thereon one or more timing means, such as a fluid restrictive device 106 and/or a capacitance device 108. As shown in the embodiment of FIG. 1, the restrictive device 106 is a variable resistor and the capacitance 108 is a variable capacitance, such as an elastomeric balloon. The restrictive device 106 and the capacitance 108 may be interchanged with similar restrictive devices or capacitances having different values and capacitances.*fn22

The `303 Patent specification further explains that various sizes and types of elastomeric balloons or other appropriate devices may be chosen from the variable capacitance device 132.*fn23 The specification does not provide for a timing means comprising switches and an electrical circuit.

In the abstract, the patentee recites that "[t]he demand gas circuit (20) of the respirator supplies respirating gas to a patient at the beginning of an inspiration and for a time period which is a fraction of the duration of the inspiration." The specification further describes this relationship as follows:

an object of this invention is to provide a respirator apparatus and method of operating the same wherein respirating gas is supplied to a patient substantially at the beginning of an inspiration and for a time period thereafter which is a fraction of the duration of inspiration.*fn24

The patentee again refines this fractional delivery method with the following statement: "Preferably the duration of application of the respirating gas to the patient is less than 0.25 of the duration of an inspiration."*fn25 In technical language, the patentee reiterates the relationship between the duration of the first fluid signal (T2-inspiration) and the second fluid signal (T1-oxygen delivery) as follows:

Thus, the second generating means 96 generates a second fluid signal on line 100, the second fluid signal having a duration related to the duration of the first fluid signal applied from output leg 70 on line 102. The duration of the first fluid signal on line 102 and the second fluid signal on line 100 are in a predetermined relationship which is dependent upon the values and sizes chosen for the timing means comprising second generating means 96. Such values and sizes should be chosen for this embodiment such that the ratio of the duration of said second fluid signal to the duration of said first fluid signal, and hence the duration of the inspiration, is less than 0.25. In many cases the ratio may approximate 0.125, if desired.*fn26

b. The `224 Patent

The specification of the `224 patent teaches:

The specification continues:

The cylinder post may be provided with various standard connection configurations, for example, with a conventional CGA 870 connection. The oxygen cylinder post 13 includes a valve 45 which is operated with a suitable wrench (not shown) to allow pressurized oxygen to flow from the cylinder 14 to the manifold 27.*fn28

The `224 patent describes a "post" as requiring a valve within the post.*fn29 In addition, the patent examiner cited nine patents*fn30 and a flyer having a photograph thereon of the OMS 50 (a prior art device manufactured by plaintiff) attached to a yoke-type regulator and mounted on the post of an oxygen tank.*fn31 Notwithstanding the references cited by the examiner, all claims in the patent application were allowed by the Patent Office.*fn32

  The specification of the `224 patent, at column 5, lines 42-46, further recites (emphasis added):
The bypass valve 30 is connected to bypass the flow control valve 31 to selectively supply a continuous flow of oxygen to the patent [sic]. The flow limiting valve 32 is connected in series with the bypass valve 30 to establish the rate of oxygen flow when the bypass valve 30 is open. The flow limiting valve 32 may be a manually adjustable needle valve which is set to the desired constant flow rate. Alternately, the flow limiting valve 32 could be replaced with a fixed orifice flow restrictor.

As stated, the flow restricting means set forth in claim 1 of the `224 patent can be a fixed orifice and need not be adjustable.*fn33 Nowhere, however, does the patent specification describe an apparatus that entirely eliminates the need for a flow limiting valve or fixed orifice flow restrictor. Nor does the patent specification directly describe an apparatus having a flow limiting valve integral with the bypass valve, such that the bypass valve might also perform the function of flow limiting valve 32. Defendant also makes the textual argument that "[t]he patentee's use of the phrase `in series with' is unmistakably clear and in contrast to the term `integral' which the patentee defines later in the specification." It points out column 7, lines 30-39, at which the patentee states:

A number of the valves and components have been described as being integral with the manifold block 27. As used herein, the term "integral" means that the components are at least mounted directly on the manifold block 27 and in some cases may share common components with the manifold block 27. For example, a valve seat may be machined directly in the manifold block 27, while other components of the valve may be mounted on the manifold block 27.

By using the phrase "in series with," defendant contends, the patentee intentionally drew a distinction between separate structures and structures that are "integral" with one another.

3. The Prosecution History of the `303 Patent

The Applicant's claims as originally filed contained no limitation directed to T1 being less than T2.*fn34 This limitation was added to overcome the Examiner's rejection of the Application based upon U.S. Patent No. 3,910,270 to Stewart, U.S. Patent No. 4,054,133 to Myers, and D. Auerbach et al. ("the Chest reference").*fn35 To distinguish Stewart,*fn36 Applicant argued that:

The operation of Stewart is easily contrasted with Applicant's claimed method. Applicant supplies a pulse of gas having duration T1 which is less than the duration T2 of negative pressure relative to ambient occurring in said in vivo respiratory system during inspiration.
Thus, even if it were argued that Stewart supplied a pulse, T1 for the pulse would equal T2 so that the patient could not inspire further.
[C]ontrary to the patent's desired time frame for respiration, Stewart supplies gas even during a time when the patient would otherwise be exhaling. With Applicant's method, on the other hand, gas supply can never last longer then the patient's inspiratory effort.*fn37

Applicant next argued that this limitation also overcame Chest. In Chest,

oxygen is supplied to the patient throughout inspiration. . . . The Chest article provides no teaching or even a clue that the supply of oxygen in the negative demand mode could be terminated earlier than the cessation of a detected negative pressure. . . .*fn38

Applicant further stated that

it cannot be said that the device described in U.S. Patent No. 4,054,133 to Myers and whose operation is reported in Chest provides a pulse of respirating gas having a duration T1 which is less than the duration T2 of inspiration as claimed by Applicant.
Applicant supplies a pulse of gas during an early part of the portion of a respiratory cycle in which a negative pressure occurs in the in vivo respiratory system, but not for the entire portion of the cycle wherein negative pressure occurs. . . . The beauty of Applicant's method is that Applicant can accomplish the same physiological result using less gas by supplying the pulse for the time T1 rather than supplying gas for the duration T2.*fn39

Applicant also recited:

[P]rior art methods and systems have attempted to supply a patient with supplemental gas either throughout respiration or throughout inspiration upon demand.
Rather than continually supplying a patient with supplemental gas, or rather than just supplying a patient with supplemental gas throughout inspiration, Applicant's method and apparatus capitalize upon the effective early stage inspiratory phenomenon recognized by Applicant. In accordance with this phenomena [sic], Applicant has concluded that it is more advantageous to apply a greater volume of respirating gas (such as oxygen) per second and to apply the oxygen only during an effective early stage of inspiration.

The pulse has a duration T1 which is less than the duration T2 of the inspiration.*fn40

The Examiner conducted an interview with Applicant on March 29, 1983. At that time, a proposed claim was submitted to distinguish the prior art of record.*fn41 The Examiner suggested revisions to the proposed claim, specifically that the limiting language "said dose being supplied only for a duration T1" be added. Applicant adopted this suggested limitation in his May 6, 1983 amendment to application Claim 58, which ultimately issued as patent Claim 3.*fn42 In that amendment, the Applicant reiterated that the limitation in the claims that T1 be less than T2 was necessary to overcome prior art references directed to devices and methods that supplied a dose of respirating gas throughout the inspiration period:

[R]ather than just supplying a patient with supplemental gas throughout inspiration (as is done by the Auerbach and Myers et al. references relied on by the Examiner), Applicant supplies a dose of respirating gas only for the duration T1 which is less than the duration T2. . . .*fn43

The Examiner, in his third and last office action, rejected application Claim 58 on obviousness grounds. In arguing that the limitation directed to T1 being less than T2 overcame the cited prior art, Applicant stated:

Auerbach et al. certainly do not recognize a method wherein the shortening of the duration of gas supply has a favorable physiological effect on a patient.
[I]t [is] inconceivable that Auerbach et al. were concerned with shortening the duration of the supply of gas to a time period less than the duration of negative pressure or that the same would even be feasible given the particular mechanical structure involved.*fn44

In so distinguishing the prior art, Applicant further explained the meaning of the limitation that T1 be less than T2. In particular, Applicant explained that the duration of the dose of gas T1 is in a predetermined relationship with the duration of inspiration T2:

[W]hile the point in time at which the supply of Applicant's dose begins is dependent upon the sensing of the initiation of inspiration, the point in time at which Applicant's dose is terminated, and hence the duration T1, is not strictly governed for each inspiration by the duration of the inspiration nor the sensitivity of the sensor.*fn45

This limitation was added by way of Applicant's October 18, 1983, Amendment. It was added to overcome U.S. Patent 4,106,503 to Rosenthal, et al., which, according to Applicant, "was cited against a corresponding foreign application filed by Applicant."*fn46

Following a second interview with the Examiner held on September 20, 1983, the Applicant amended application Claim 58 to include the limitation "using timing means to predetermine a duration T1."*fn47 The Applicant describes the claimed "timing means" as follows:

The choice of values and sizes for the particular elements (particularly the resistance 106 and the capacitance 108) determine the duration of the second fluid signal which controls the application of a dose to the patient. In this regard, the specification states at page 18 that "An appropriate value is chosen for the resistance of a variable resistor 106 and a capacitance 108 of appropriate maximum capacity is chosen so that the first fluid signal traveling around the closed loop fluidic circuit 104 will be delayed for a predetermined time before the signal reaches the second end 104b of the fluidic circuit."*fn48

The relationship between T1 and T2 is further acknowledged and emphasized in patent Claims 4 and 5, which depend upon Claim 3 of the `303 patent. These dependent claims recite specific relationships between T1 and T2 as follows:

4. The method of Claim 3, wherein T1 is less than 0.25xT2.
5. The method of Claim 3, wherein T1 is less than 0.5 second.

Finally, following Applicant's request that the Rosenthal patent "be made of record in the prosecution file of the Captioned application," Applicant distinguished the claimed invention over Rosenthal by stating that "the Rosenthal et al. apparatus requires a reset switch 34, meaning that the apparatus is not capable of operating in an automatically recycling mode in the manner claimed by Applicant."*fn49

In all, the patent examiner cited eighteen patents*fn50 and three articles*fn51 considered during the examination of the `303 patent. Notwithstanding the acknowledged prior art and the references cited by the examiner, claims 3, 4 and 5 as amended were ultimately allowed by the Patent Office.*fn52

C. Sunrise's Entry Into the OCD Market

In 1993, Sunrise purchased DeVilbiss and operated it as a subsidiary until it became a division of Sunrise.*fn53 The following year, Sunrise purchased the assets of PulsAir.*fn54 PulsAir owned the `303 patent and sold an OCD under the name of OMS 20/50, which utilized this patented technology.*fn55 Sunrise began selling the OMS 20/50 immediately after its purchase of PulsAir and continued to market it until the summer of 1997.*fn56 The OMS 20/50 utilized the technology claimed in the `303 patent inasmuch as it used a timing means to time the delivery of the pulses of oxygen, which would be supplied at the onset of inspiration and only for a duration of time less than the time of inspiration.*fn57

In 1995, Sunrise put together a team to develop its next generation OCD product. Gregory W. Good, Richard L. Dalton and Peter Gilcrest invented the subject matter which later became the EX 2000.*fn58 They applied for a patent which issued on May 26, 1998 as the `224 patent. The inventors, as is customary in such circumstances, assigned their right and interest in the `224 patent to their employer, Sunrise.*fn59 The new EX 2000 OCD was first shown to the marketplace at the November 1996 MedTrade show.*fn60 Sunrise invested at least $526,319 in wages, materials and capital expenses to develop the EX 2000.*fn61

The EX 2000 differs significantly from the OMS 20/50. First, the EX 2000 is made to be used only on oxygen cylinders with an 870 style post, because, unlike the OMS 20/50, the EX 2000 has an internal regulator adapted only to such a post. Second, the EX 2000 fits directly over the oxygen cylinder post and does not hang off to the side as the OMS 20/50 and its external regulator do. Third, the EX 2000 has an internal pressure relief valve, as well as a bypass valve to provide a flow of oxygen around the control valve when continuous flow rather than pulsed oxygen is desired, or in the event of battery failure. The OMS 20/50 had neither an internal regulator nor pressure relief valve. The EX 2000 also has a flow restrictor to limit flow through the bypass valve to an acceptable dosage rate of 2 liters per minute. Finally, the EX 2000 does not utilize the internal tubing of the OMS 20/50. The functions are instead designed into the manifold block.*fn62 According to Greene, the EX 2000 utilizes the technology of both the `224 patent and claims 3 to 5 of the `303 patent.*fn63

D. AirSep's Development of the ImPulse Select

AirSep developed its first OCD in 1996, under the name of ImPulse, with a company named Medisonic. The ImPulse was first commercially available in November 1996.*fn64 The ImPulse was designed to compete directly with the Chad OCD.*fn65 Like the Chad unit, the ImPulse provides a pulse of oxygen on intermittent breaths, and, like both the Chad OCD and the OMS 20/50, utilized an external regulator.*fn66 AirSep still sells the ImPulse today, albeit in minuscule quantities.*fn67

In the summer of 1997, AirSep decided to develop a new OCD. This project commenced with a meeting during which the design of the EX 2000 was reviewed and discussed.*fn68 The principal designer of the ImPulse Select was Norman McCombs,*fn69 one of whose first actions was to take apart and examine an EX 2000*fn70 that had been given to him by Joseph Priest, the President of AirSep.*fn71 McCombs performed an extensive evaluation of all aspects of the EX 2000, by means of visual inspection, disassembly and measuring the pressures.*fn72

As developed, the ImPulse Select has three modes, an "A" mode, a "B" mode and a continuous flow mode.*fn73 During development, the "A" mode was referred to by AirSep as the "AirSep" or Chad mode because it provides the same type of dosing methodology as the Chad and the original ImPulse devices.*fn74 The "B" mode was referred to by AirSep as the "DeVilbiss" mode because it provides the same type of dosing methodology as the Sunrise/DeVilbiss EX 2000,*fn75 providing oxygen for the selected pulse time on every breath.*fn76 The "B" mode of the ImPulse Select was specifically designed by AirSep to include the same functionality as is provided by the Sunrise/DeVilbiss EX 2000,*fn77 that is, to incorporate varying pulse widths on switch-selectable settings numbered from "one" to "six."*fn78 The ImPulse Select also has a continuous flow mode, like the EX 2000.*fn79

The ImPulse Select was introduced to the market at the MedTrade show in November 1998.*fn80 The AirSep employees manning the display booth at the show marketed the new OCD as working just like the EX 2000.*fn81

Like Sunrise's OCDs, the AirSep ImPulse Select senses the initiation of inspiration.*fn82 It then provides a dose of respirating gas immediately in response to sensed inspiration.*fn83 The ImPulse Select supplies a pulse of oxygen in response to the detection of inhalation by the pressure sensor. The length of this pulse is predetermined, not by fluidic circuitry as in the `303 patent, but by a resistor and capacitor network comprising an electronic timing means.*fn84

Thus, the ImPulse Select has a timer that controls the predetermined time T1.*fn85 Every time the OCD senses a breath, a resistor and capacitor in the timing circuit predetermine the time that the delivery valve will be on.*fn86 When a patient uses the ImPulse Select, the duration of T1 is less than the duration of T2 in the vast majority of circumstances.*fn87 The ImPulse Select can provide oxygen during exhalation, but only if the patient is breathing very rapidly, so that the inspiration time is very short, and the ImPulse Select was set at its higher settings, giving a long pulse duration.*fn88 There was testimony to the effect that this would happen less than one percent of the time.*fn89 AirSep acknowledged that only 0.3% of the ImPulse Select units shipped are returned for this reason.*fn90

Only when the ImPulse Select is operated in the "B" mode at setting "6" would oxygen be supplied during exhalation, and then only to patients at breathing rates of more than 35 breaths per minute. Flow rate 6 is the longest flow rate setting of the ImPulse Select; if that setting is reduced, the likelihood of a patient ever receiving oxygen during exhalation is likewise reduced.*fn91 At settings 1 to 5 of the ImPulse Select, a patient will not be supplied with oxygen during exhalation even at 35 breaths per minute.*fn92

For every setting of the ImPulse Select, except setting 6 in the B mode, T1 is less than 0.5 second.*fn93 Assuming that 10% of users of the ImPulse Select have restrictive lung disease, only 0.23% of ImPulse Select users would have an inspiration period of less than one-half second.*fn94 Indeed, in seven of the twelve possible settings of the ImPulse Select, T1 is less than .25 times T2 when the inspiration period is one second or greater.*fn95

The ImPulse Select also has a flow restricting orifice. The valve seat of the ImPulse Select bypass valve has the smallest cross-sectional area of any part of the bypass path. This orifice controls the rate of flow to 2 liters per minute, and oxygen must pass through this orifice (in continuous flow mode) to reach the patient.*fn96 Thus, the bypass circuit of the ImPulse Select has a valve which includes a choking (restricting) orifice that controls flow. Oxygen through this circuit moves from an inlet port, past the valve components, through a valve seat containing the choking orifice, and into the outlet port.

Plaintiff contends that these two components are arranged in a serial manner as required by the `224 patent.*fn97 The fact that the valve seat of the ImPulse Select bypass valve and the choking orifice are coincident, it argues, does not alter the function of the units. If the valve seat of the ImPulse Select and the choking orifice were separated, plaintiff asserts that the function would remain the same.*fn98

AirSep stipulates that the ImPulse Select has every element of the claims of the `224 patent except the flow restricting means "in series with" the bypass valve.*fn99 The infringement analysis of the `224 patent is therefore dependent entirely on the resolution of that sole issue.

E. The Witnesses

Dr. David Greene is the Vice President of Technology for the Respiratory Products Division of Sunrise Medical HHG, Inc.*fn100

Mr. Richard Kocinski is the President of the Respiratory Products Division of Sunrise Medical HHG, Inc.*fn101

Mr. Peter Bliss, Sunrise's technical expert, is a partner in a consulting firm called Valley Inspired Products. Valley Inspired Products does design engineering consulting, product testing, education and marketing services, all directed at respiratory product manufacturers.*fn102 Mr. Bliss has been a paid consultant to Sunrise prior to his involvement in this litigation.*fn103 Mr. Bliss has been paid approximately twenty thousand dollars by Sunrise for a project of redesigning one of Sunrise's liquid oxygen units.*fn104

Dr. William Messner, Sunrise's technical expert, is an associate professor at Carnegie Mellon University.*fn105

Mr. James Alessi is an engineer at AirSep Corporation and is a named inventor on a utility and design patent directed to the ImPulse Select.*fn106

Mr. Norman McCombs is the Senior Vice President of AirSep.*fn107 Mr. McCombs is a named inventor on a utility and a design patent application directed to the ImPulse Select and a separate patent application directed to the bypass valve of the ImPulse Select.*fn108

Mr. Joseph L. Priest is the President and Chief Operating Officer of AirSep Corp.*fn109

Mr. Mark Mizerkiewicz is an engineer and a research and design manager at AirSep Corporation and has been employed by AirSep since 1996.*fn110

Mr. Andrzej Klimaszewski is a senior project engineer for AirSep Corporation who specializes in electronics.*fn111 Mr. Klimaszewski has been an AirSep employee approximately eight years.*fn112

Mr. Donald Hunter is an engineering manager with Sunrise and was the designated corporate witness on the issue of Sunrise's testing and comparison of the accused device.*fn113

Mr. Gregory Good is a former employee of Sunrise and one of the named inventors of the `224 Patent.*fn114 Mr. Good left the employ of Sunrise in February of 1997.*fn115

Mr. Daniel Easley is the former President of the Respiratory Products Division at Sunrise and is the current President of Sunrise's Mobility Products Division at Sunrise. He left his position as President of the Respiratory Products Division in May of 1999.*fn116

Mr. Sam Kumar, AirSep's expert, is the President of Teknocraft, Inc., a valve/control component designer and manufacturer located in Florida.*fn117 Mr. Kumar has an extensive background in fluidic control components, having studied the same while obtaining his master's degree in mechanical engineering and subsequently working for the Corning Fluidics Department for approximately five years.*fn118 In addition, Mr. Kumar taught certain courses and seminars while working for Corning.*fn119 Mr. Kumar is a named inventor on several patents directed to valves and valve components.*fn120 Mr. Kumar has worked with Puritan Bennett and Sunrise Medical in the past.*fn121

Mr. Ronald Kareken is a registered patent attorney and counsel to AirSep Corporation.*fn122

F. Likelihood of success on the merits

1. Ownership

AirSep disputes Sunrise's claim to ownership of the `224 Patent,*fn123 because no assignment history of the `224 Patent was introduced into evidence, either by way of documentary evidence or witness testimony on the patent's chain of title.*fn124 Sunrise, however, points to evidence that the inventors of the `224 patent directly assigned all their right and title to the patent to Sunrise, and that Sunrise consequently owns all right and title to the `224 patent.*fn125 I conclude that Sunrise does in fact own the `224 patent.

Sunrise also purports to own the `303 Patent.*fn126 This ownership claim is more problematic, requiring an examination of a somewhat convoluted chain of title. Dr. Gerald Durkan, the named inventor of the `303 Patent, assigned certain rights to the `303 Patent to Tritec, Inc. through an assignment dated June 8, 1982. Dr. Durkan kept a reversionary interest to the `303 Patent.*fn127 Tritec, Inc. assigned its rights, title and interest to the `303 Patent to TriTec Industries on May 26, 1983. PX 21 and 22.*fn128 On or before August 1983, CRYO2 Corporation purchased TriTec Industries, Inc.*fn129

On August 1, 1983, TriTec Industries, Inc. (a subsidiary of CRYO2 Corporation) granted what purports to be a security interest in the `303 patent to Kircaldie, Randall & McNabb.*fn130 That document is drafted as a conditional assignment which, if the underlying note is paid, is then void; otherwise and until then, it grants a full assignment of the patent to Kircaldie. On July 5, 1984, TriTec Industries, Inc. granted a conditional assignment and second security interest to State Street Bank and Trust Company.*fn131

On February 8, 1988, CRYO2 Corporation assigned all interest in the `303 patent of both it and its subsidiary TriTec Industries, Inc. to DOC Technologies, Inc.*fn132 Also on February 8, 1988, DOC Technologies, Inc. granted a security interest in the `303 patent to Healthdyne, Inc.*fn133 On July 7, 1989, DOC Technologies, Inc. assigned its interest in the `303 patent to PulsAir Anstalt.*fn134 On January 18, 1994, PulsAir Anstalt assigned its interest in the `303 patent to DeVilbiss Health Care, Inc., which was at that time a wholly-owned subsidiary of Sunrise.*fn135 On June 27, 1997, Sunrise merged with its wholly-owned subsidiary, DeVilbiss Health Care, Inc., so that DeVilbiss Health Care, Inc. was no longer a separate company, but instead became a Sunrise division. The interest of DeVilbiss Health Care, Inc. was thus assigned to Sunrise.*fn136

Defendant contends that no assignment exists from any entity to CryO2 of the rights to the `303 Patent. Thus, when CryO2 executed an assignment of the patent on February 8, 1988 to DOC Technologies, CryO2 did not in fact own any right, title or interest to the `303 Patent. And even if CryO2 did have rights to the `303 Patent at one time, defendant argues, it transferred those rights to Kircaldie, Randall & McNabb by way of security interest five years before it purported to assign them to DOC Technologies.

As a result, defendant argues, the February 8, 1988 assignment from CryO2 to DOC Technologies did not transfer any rights to the `303 Patent. If defendant is correct, this defect in title would appear to propagate down the entire chain: i.e., as of July 7, 1989, DOC Technologies did not own any rights to the `303 Patent, so its assignment to PulsAir Anstalt did not work to transfer any interest in the patent, either.

On August 15, 1991, Kircaldie and Durkan executed nunc pro tunc assignments, effective February 8, 1988 and July 6, 1989, respectively, of their security and reversionary interests in the `303 patent to DOC Technologies, Inc.*fn137 Defendant complains that the nunc pro tunc assignments are nothing more than an attempt to validate what it considers to be the previously ineffective, encumbered, July 7, 1989 assignment from DOC Technologies to PulsAir Anstalt, from which, of course, DeVilbiss purportedly acquired its interest in the `303 Patent which it later assigned to plaintiff. Thus, defendant argues that if the nunc pro tunc agreement is invalid, DOC Technologies never owned any right, title or interest to the `303 Patent and neither does Sunrise;*fn138 if Sunrise does not own the `303 Patent, Sunrise does not have standing to bring the instant patent infringement action based on the `303 Patent.

2. Infringement

a. The `303 Patent

i. Whether AirSep's ImPulse Select "Employed a Method" in Violation of the `303 Patent

Defendant argues that Sunrise adduced no evidence, testimonial or documentary, that AirSep has employed a method using the ImPulse Select that infringes the method of Claim 3 of the `303 Patent. To the contrary, it contends that the evidence adduced shows only that AirSep manufactures and sells the ImPulse Select device to its customers, home health care dealers, who, in turn, provide the device to patients needing such a device.*fn139

ii. Alleged Non-infringement of Invacare Venture Device

Dr. Greene performed an infringement analysis of the `303 Patent as compared to a device called the Invacare Venture.*fn140 one of the salient features of which is that the valve always remains open for a fixed duration of one second.*fn141 If a patient on the Invacare Venture breaths rapidly enough, his or her inspiration time may be less than one second,*fn142 in which case the Invacare Venture would provide a dose of oxygen during a portion of the patient's exhalation.*fn143

As discussed supra, claim 3 of the `303 Patent requires that the dosage interval T1 always be less than the inspiratory period T2, but notably, according to defendant, Sunrise never sued Invacare for infringement of the `303 Patent.*fn144 The ImPulse Select also provides a dose of oxygen for a range of fixed periods of time, dependent on the positions of the various selector switches.*fn145 Plaintiff responds that it is irrelevant that Invacare was never sued for infringement of the `303 patent because the Invacare Venture had an inspiration period that was always one second.*fn146 In contrast, the longest pulse time of the ImPulse Select in the B6 setting is only 0.5 second.*fn147 Thus, far fewer patients are likely to receive a dose of oxygen during exhalation with the ImPulse Select than with the Venture.

iii. Non-infringement Defense of Providing a Dose During Exhalation

(A.) Claim Construction Testimony

No claim, including claim 3, of the `303 Patent requires normal breathing patterns as a limitation of the claim,*fn148 nor does Claim 3 require normal operating circumstances or conditions as a limitation.*fn149 In addition, the `303 Patent specification does not describe normal or typical breathing patterns as a qualification to the limitation of T1 being less than T2.*fn150 Rather, T1 must always be less than T2 in order for the claim to be satisfied.*fn151

(B.) The Accused Device Can Provide a Dose of Oxygen during Exhalation

Defendant argues that the use of the ImPulse Select does not practice a method with a step of "using timing means to predetermine a duration T1 for which a dose of respirating gas is to be supplied to said in vivo respiratory system, said duration T1 being less than the duration T2 of negative pressure relative to ambient pressure occurring in said in vivo respiratory system during said inspiration period."*fn152 Plaintiff, for its part, admits that the accused device can (although almost never does) provide oxygen during exhalation,*fn153 but emphasizes that the ImPulse Select, operating in "B" mode, was designed and is intended to supply oxygen to a patient only during inhalation.*fn154 In support of that contention, plaintiff notes that the ImPulse Select patient manual provides that an "actual oxygen delivery to the patient occurs only at the exact point in the breathing cycle when the patient starts to inhale," and that "the ImPulse Select does not deliver oxygen during exhalation."*fn155 It also points out that there are no AirSep documents or advertisements indicating that the ImPulse Select is intended to provide oxygen during exhalation, and that the ImPulse Select has never been marketed as anything but a device that provides oxygen only during inhalation.*fn156

AirSep has received complaints from customers who have returned the ImPulse Select because it provided a dose during exhalation,*fn157 but only 0.3% of the users of the ImPulse Select have experienced the provision of oxygen during exhalation and returned the OCD.*fn158 Thus, some number of ImPulse Select users less than 99.7% do not receive oxygen during exhalation. Through March of 1999, only four out of 3,039 ImPulse Select units were returned because of the provision of oxygen during exhalation. This return ratio has remained consistent. There has not been a month where more than two ImPulse Select units were returned due to the provision of oxygen during exhalation.*fn159

Specifically, the roughly 0.3% of the users of the ImPulse Select who receive oxygen during exhalation do so because of their unusual breathing pattern, such as excessive exhaling or hyperventilation.*fn160 These are the only reasons of which AirSep is aware that will cause a patient to receive oxygen during exhalation.*fn161 When an AirSep customer calls to complain that an ImPulse Select is providing oxygen during exhalation, the customer is forwarded to the product manager who explains that 0.3% of the population may have a breathing pattern that is not conducive to use with the ImPulse Select.*fn162

Although there is no AirSep literature where the average human breathing rate is referred to as anything but 20 breaths per minute,*fn163 Mr. Bliss' charts for breathing frequencies of 35 breaths/min., 40 breaths/min., and 60 breaths/min. demonstrate the ImPulse Select providing oxygen during exhalation at flow setting 6.*fn164 Mr. Bliss' charts for breathing frequency were tested at an Inspiration over Exhalation (I/E) ratio of 1 to 2.*fn165

Patients with restrictive lung disease are candidates for an ImPulse Select OCD device.*fn166 According to an article by Dr. Tobin, approximately five percent of patients with restrictive lung disease have an inspiratory time of less than 0.5 seconds.*fn167 These patients tend to breathe faster with more time spent inhaling and have an I/E ratio of 1 to 2 or 1 to 2.5.*fn168 The average inspiration period for restrictive lung disease patients is 0.96 seconds with a standard deviation of 0.24.*fn169 Statistical analysis predicts that only 2.28% of these patients would have an inspiration period less than .5 second which is the longest pulse setting on the ImPulse Select. Also, only about 10% of the users of the ImPulse Select have restrictive lung disease. Hence, plaintiff argues that only 0.228 percent of the users of the ImPulse Select would use the ImPulse Select in a manner that does not practice the method of claims 3 to 5.*fn170

Chronic obstructive pulmonary disease (COPD) patients, however, are also candidates for an Impulse Select OCD device, and these patients may have I/E ratios of 1 to 3 or 1 to 4.*fn171 With these I/E ratios, the inspiration time is shorter and the inspiration peak on the charts is narrower.*fn172 Thus, at only 30 breaths per minute and an I/E ratio of 1 to 4, the pulse delivered by the ImPulse Select would extend beyond the inspiration period.*fn173

Nevertheless, a more typical patient with a one second inspiration period using the ImPulse Select would never be provided oxygen during the exhalation period and would appear to practice the method of claim 3 of the `303 patent.*fn174 Only under the above-discussed unusual circumstances involving the ImPulse Select operating in Mode B at setting 6 and the patient breathing at a rate in excess of about 30-35 breaths per minute will a patient using the ImPulse Select receive oxygen during expiration.*fn175

Turning to the technical reasons why the ImPulse Select can deliver a dose of oxygen during expiration, the monostable vibrator used in the ImPulse Select's control circuit provides a signal to the valve for a fixed duration which is unaffected by anything in the patient's breathing pattern once it starts to deliver.*fn176 Because the duration of the pulse is fixed, if a patient starts exhaling before the pulse actually ends, the dose will be partially delivered during exhalation.*fn177 The ImPulse Select will therefore deliver a dose of oxygen to a patient while the patient exhales if the inhalation time is less than pulse delivery time.*fn178 Providing a dose during exhalation and having the dose extend beyond inspiration are characteristics of the device as a result of the design of the circuit.*fn179

The ImPulse Select can also pulse a dose that begins during exhalation. The balancing circuit responds to high pressure in the tubing. Usually, that high pressure is generated when the valve opens. In some cases, however, a patient will generate a high enough pressure during exhalation to cause the balancing circuit to be activated.*fn180 Once this happens, the balance becomes upset.*fn181 This condition will be interpreted by the circuit as an inhalation, causing triggering to occur and oxygen to be delivered. This pulsing is also due to the structure of the balancing circuit.*fn182

In view of these facts, Mr. Kumar's professional and expert opinion, reached with a reasonable degree of professional certainty, is that the method used by the accused device does not infringe Claim 3 of the `303 Patent, either literally or under the doctrine of equivalents.*fn183

(C.) The FDA Investigation

The Food and Drug Administration ("FDA") has regulatory authority over OCDs and their manufacturers.*fn184 In early 1999, the FDA contacted AirSep in follow-up to a customer's comment under the MEDWATCH program that the ImPulse Select device's propensity to fire upon exhalation had caused a hypoxic condition with certain patients.*fn185

The FDA sent AirSep a copy of the MEDWATCH report on or about March 3, 1999, and also visited AirSep in February/March of 1999. Priest Tr. 2/9:63-4. The FDA also initiated an investigation of AirSep. Priest Tr. 2/9:63. The FDA investigated the design operation, the inspection criteria, and manufacturing with respect to the ImPulse Select. Priest Tr. 2/9:66. Mr. Priest informed the FDA that ImPulse Select is designed to provide pulses of oxygen only on inhalation and not on exhalation, and only in a single pulse.*fn186 The FDA issued its observations report, to which AirSep responded.*fn187 AirSep was not required to change the design or the mechanics of the ImPulse Select.*fn188

iv. Equivalence of Fluidic Control Versus Electronic Control

Defendant argues that the use of the ImPulse Select does not practice a method with a step of "using timing means to predetermine a duration T1" because the timing means of the ImPulse Select uses an electronic resistor-capacitor ("RC") circuit rather than a fluidic RC circuit.*fn189 Plaintiff, however, contends that use of the ImPulse Select infringes claim 3 of the `303 patent because its electronic timing means*fn190 is essentially the same as the fluidic timing means disclosed in the specification of the `303 patent.*fn191 According to plaintiff, the fluidic timing means of the `303 patent and the electronic RC timing means of the ImPulse Select perform identical functions in substantially the same way, and an electronic timing circuit could be substituted for the fluidic timing circuit disclosed in the `303 patent.*fn192

Fluidic control circuits were designed to be the equivalent of electronic control circuits.*fn193 Indeed, in the late sixties to seventies, fluidics was a very important science*fn194 and was thought of as a technology that was going to "take over the control systems world."*fn195 When fluidics was first developed, it was intended that fluidics and electronics would be used for the same purposes, although fluidics proved impractical in some applications.*fn196 Researchers were applying fluidics to a wide variety of applications, numerous papers were published on the subject, and researchers even tried to make a fluidically controlled computer, which failed to attain success because of its unwieldy size.*fn197 The science of fluidics ultimately died out as electronic circuits became much less susceptible to heat, more efficient, more reliable, and more desirable from size and operational standpoints.*fn198

Fluidic circuits are not interchangeable with electronic circuits because fluidic circuits are different in reliability, accuracy, controllability, and function.*fn199 In selected applications of information processing and timing, however, fluidics can perform the same function as electrical control systems.*fn200 In fact, there was expert testimony that fluidic timing means are structurally and functionally equivalent to electronic timing means for the purposes of OCDs.*fn201 At the time the application for the `303 patent was filed, however, it would have been impractical to use an electronic timing means for this type of portable OCD due to the lack of sufficient electronic sensor technology as well as the increased size that would have been necessary to house an electronic timing means.*fn202

The structural construction of the claimed timing means in the `303 patent is a fluidic device that uses fluidic resistors or needle valves and a capacitor which is a movable diaphragm.*fn203 The capacitance of the timing means is a variable capacitance, such as an elastomeric balloon.*fn204 A fixed volume capacitance could not adequately perform this function and would be incompatible with the low pressures used in the fluidic logic circuit discussed herein.*fn205 The capacitance of the ImPulse Select, in contrast, is an electrical capacitor.*fn206 According to plaintiff's own expert, Mr. Bliss, an elastomeric balloon does not share a single structural similarity with an electrical capacitor.*fn207

The resistance described in the `303 Patent is not an electrical resistor, but a variable orifice or needle valve.*fn208 According to Mr. Bliss, there is not one structural similarity between the electronic resistor of the ImPulse Select and the fluidic resistor in the `303 Patent.*fn209

Ohm's Law states that volts equals current times resistance, and most electronic circuits perform pursuant to Ohm's law. Using a linear version of Ohm's law, the relationship between voltage and current will be linear as well.*fn210 The RC circuit of the ImPulse Select is a linear device such that the linear version of Ohm's law applies.*fn211

In contrast, the relationship between pressure and flow in a fluidic circuit, in many cases, is not linear.*fn212 Specifically, the relationship between pressure and flow in the fluidic circuit described in the `303 Patent may not be linear.*fn213

v. Whether the Sequence of Steps of the ImPulse Select Matches the Sequence of Steps ...

Buy This Entire Record For $7.95

Download the entire decision to receive the complete text, official citation,
docket number, dissents and concurrences, and footnotes for this case.

Learn more about what you receive with purchase of this case.