DCT

8:12-cv-02206

Masimo Corp v. Mindray DS USA Inc

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 8:12-cv-02206, C.D. Cal., 08/05/2013
  • Venue Allegations: Plaintiff alleges venue is proper based on a prior contractual agreement between the parties in which Defendant consented to personal jurisdiction and venue in the United States District Court for the Central District of California.
  • Core Dispute: Plaintiff alleges that Defendant’s pulse oximetry patient monitoring devices and sensors infringe nine patents related to signal processing techniques for extracting physiological data from noisy signals.
  • Technical Context: The technology at issue is pulse oximetry, a noninvasive method for monitoring a patient's blood oxygen saturation and pulse rate, which is a standard of care in clinical settings.
  • Key Procedural History: The complaint alleges that the parties entered into a "Purchasing And Licensing Agreement" in 2002, which was subsequently amended multiple times. The complaint asserts claims for both patent infringement and breach of this contract. Plaintiff also alleges it provided Defendant with pre-suit notice of infringement of six of the nine asserted patents, which may form the basis for a subsequent claim of willful infringement.

Case Timeline

Date Event
1997-04-14 U.S. Patent No. 6,002,952 Priority Date
1997-10-06 U.S. Patent No. 6,263,222 Priority Date
1999-12-14 U.S. Patent No. 6,002,952 Issued
2001-07-17 U.S. Patent No. 6,263,222 Issued
2002-11-13 Original Purchasing and Licensing Agreement signed
2003-06-17 U.S. Patent No. 6,580,086 Issued
2003-11-13 Agreement Amendment One signed
2004-03-02 U.S. Patent No. 6,699,194 Issued
2004-06-01 U.S. Patent No. 6,745,060 Issued
2007-05-08 U.S. Patent No. 7,215,986 Issued
2008-05-01 Mindray acquires Datascope Corporation (approx. date)
2008-06-23 Agreement Amendment Two signed
2009-02-10 U.S. Patent No. 7,489,958 Issued
2009-03-24 U.S. Patent No. 7,509,154 Issued
2010-01-01 Agreement Amendment Three signed (approx. date)
2010-04-01 Agreement Amendment Four signed (approx. date)
2011-04-20 Agreement Amendment Five signed (approx. date)
2011-11-09 Masimo sends Official Intent to Audit
2012-02-27 Masimo notifies Mindray of a dispute under the Agreement
2012-04-01 Agreement Amendment Six signed (approx. date)
2012-05-14 Masimo provides additional detail on alleged breaches
2012-07-01 Agreement Amendment Seven signed (approx. date)
2012-07-24 U.S. Patent No. 8,229,533 Issued
2013-08-05 First Amended Complaint Filed

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 6,002,952 - "Signal Processing Apparatus and Method"

  • Patent Identification: U.S. Patent No. 6,002,952, "Signal Processing Apparatus and Method," issued December 14, 1999 (Compl. ¶11).

The Invention Explained

  • Problem Addressed: The patent describes the difficulty of extracting a desired physiological signal, such as a plethysmographic waveform used in pulse oximetry, from a composite measured signal that also contains a secondary, "noise" portion, particularly when the noise occupies the same frequency spectrum as the desired signal ('952 Patent, col. 1:35-43). Patient motion is identified as a primary source of such noise, which renders conventional filtering techniques ineffective ('952 Patent, col. 2:15-19).
  • The Patented Solution: The invention proposes a method where two measured signals are acquired, typically at different wavelengths of light (e.g., red and infrared). The signals are modeled as each containing a primary (desired) portion and a secondary (undesired) portion. The method involves generating a third signal indicative of the ratio of the two measured signals and processing this third signal to remove the secondary (noise) portions, resulting in a "scrubbed" or clean fourth signal from which a physiological parameter like pulse rate can be accurately determined ('952 Patent, Abstract; Fig. 12).
  • Technical Importance: This signal processing approach represented a potential solution to the problem of motion artifact, a significant limitation that could cause conventional pulse oximeters to provide unreliable or no readings during patient movement (Compl. ¶¶14-17).

Key Claims at a Glance

The complaint does not identify specific claims asserted against the accused products (Compl. ¶¶56-60). A representative independent claim is analyzed below.

  • Independent Claim 1: A method for determining a patient's true pulserate, comprising the steps of:
    • acquiring a first measured signal, said first measured signal containing a primary portion and a secondary portion;
    • acquiring a second measured signal, said second measured signal containing a primary portion and a secondary portion;
    • generating a third signal, said third signal indicative of the ratio of said first measured signal to said second measured signal;
    • processing said third signal to remove said secondary portion of said first measured signal and said secondary portion of said second measured signal from said first and second measured signals respectively, said processing resulting in a fourth signal; and
    • determining said true pulserate from said fourth signal.

U.S. Patent No. 6,263,222 - "Signal Processing Apparatus"

  • Patent Identification: U.S. Patent No. 6,263,222, "Signal Processing Apparatus," issued July 17, 2001 (Compl. ¶12).

The Invention Explained

  • Problem Addressed: The patent addresses the challenge of separating a primary signal (e.g., physiological data) from a secondary signal (e.g., motion-induced noise) when they are combined in a measured signal, a problem particularly acute in physiological monitoring ('222 Patent, col. 1:11-20).
  • The Patented Solution: The invention discloses a signal processor that acquires two correlated signals. It combines these signals to generate a "secondary reference" signal that is a function primarily of the noise components. This secondary reference is then used in a correlation canceler to remove the noise from one of the original measured signals. The processor can also generate a "primary reference" that is a function of the desired signal portions, which can then be used to remove the desired signal to isolate the noise component. ('222 Patent, Abstract; col. 4:1-12).
  • Technical Importance: This patent provides a specific framework, using correlation cancellation, for separating signal from noise in physiological measurements, thereby enhancing the reliability of devices like pulse oximeters in real-world clinical conditions involving patient motion (Compl. ¶¶14-17).

Key Claims at a Glance

The complaint does not identify specific claims asserted against the accused products (Compl. ¶¶61-65). A representative independent claim is analyzed below.

  • Independent Claim 1: A signal processor for receiving a first and second signal, each having primary and secondary portions, the processor adapted to:
    • combine said first and second signals to generate a secondary reference having a significant component which is a function of said first and said second secondary signal portions; and
    • combine said first and second signals to generate a primary reference having a significant component which is a function of said first and second primary signal portions.

U.S. Patent No. 6,580,086 - "Shielded Optical Probe and Method"

  • Patent Identification: U.S. Patent No. 6,580,086, "Shielded Optical Probe and Method," issued June 17, 2003 (Compl. ¶13).
  • Technology Synopsis: This patent describes an optical probe for patient monitoring that incorporates light shields. The shields are designed to reduce the amount of ambient and reflected light that reaches the detector, thereby mitigating sources of noise and increasing measurement accuracy.
  • Asserted Claims: The complaint does not specify which claims are asserted (Compl. ¶¶66-71).
  • Accused Features: The complaint alleges infringement by "Mindray Reusable Sensors" (Compl. ¶68).

U.S. Patent No. 6,699,194 - "Signal Processing Apparatus and Method"

  • Patent Identification: U.S. Patent No. 6,699,194, "Signal Processing Apparatus and Method," issued March 2, 2004 (Compl. ¶14).
  • Technology Synopsis: This patent discloses a signal processing method that transforms a measured physiological signal into a spectral domain. It then applies a set of rules to the spectral peaks to determine a pulserate, which is designed to be more robust against distortions like those caused by an irregular heartbeat or motion.
  • Asserted Claims: The complaint does not specify which claims are asserted (Compl. ¶¶72-76).
  • Accused Features: The complaint alleges infringement by "Mindray SpO2 Products and Systems" (Compl. ¶74).

U.S. Patent No. 6,745,060 - "Signal Processing Apparatus"

  • Patent Identification: U.S. Patent No. 6,745,060, "Signal Processing Apparatus," issued June 1, 2004 (Compl. ¶15).
  • Technology Synopsis: This patent describes a method for analyzing measured signals by modeling them as containing primary (desired) and secondary (undesired) portions. It discloses using various techniques, including statistical functions or Fourier transforms, to determine coefficients that relate the two signals, which can then be used to isolate the desired information.
  • Asserted Claims: The complaint does not specify which claims are asserted (Compl. ¶¶77-81).
  • Accused Features: The complaint alleges infringement by "Mindray SpO2 Products and Systems" (Compl. ¶79).

U.S. Patent No. 7,215,986 - "Signal Processing Apparatus"

  • Patent Identification: U.S. Patent No. 7,215,986, "Signal Processing Apparatus," issued May 8, 2007 (Compl. ¶16).
  • Technology Synopsis: This patent details a method for analyzing measured signals by combining two signals to create a reference signal correlated with noise, and using that reference in a correlation canceler to remove the noise. The invention is described in the context of physiological monitors and determining characteristics such as pulse or blood pressure.
  • Asserted Claims: The complaint does not specify which claims are asserted (Compl. ¶¶82-86).
  • Accused Features: The complaint alleges infringement by "Mindray SpO2 Products and Systems" (Compl. ¶84).

U.S. Patent No. 7,489,958 - "Signal Processing Apparatus and Method"

  • Patent Identification: U.S. Patent No. 7,489,958, "Signal Processing Apparatus and Method," issued February 10, 2009 (Compl. ¶17).
  • Technology Synopsis: This patent describes a signal processing method for determining a pulserate from a noisy signal. The method involves transforming the signal into a spectral domain and applying rules to the resulting spectral peaks, a technique intended to be robust against noise and signal distortion.
  • Asserted Claims: The complaint does not specify which claims are asserted (Compl. ¶¶87-91).
  • Accused Features: The complaint alleges infringement by "Mindray SpO2 Products and Systems" (Compl. ¶89).

U.S. Patent No. 7,509,154 - "Signal Processing Apparatus"

  • Patent Identification: U.S. Patent No. 7,509,154, "Signal Processing Apparatus," issued March 24, 2009 (Compl. ¶18).
  • Technology Synopsis: This patent describes a signal processing system for analyzing measured signals that contain both desired and undesired portions. It discloses techniques such as correlation cancellation using reference signals derived from multiple measured signals to isolate the desired physiological information.
  • Asserted Claims: The complaint does not specify which claims are asserted (Compl. ¶¶92-96).
  • Accused Features: The complaint alleges infringement by "Mindray SpO2 Products and Systems" (Compl. ¶94).

U.S. Patent No. 8,229,533 - "Low-Noise Optical Probes For Reducing Ambient Noise"

  • Patent Identification: U.S. Patent No. 8,229,533, "Low-Noise Optical Probes For Reducing Ambient Noise," issued July 24, 2012 (Compl. ¶19).
  • Technology Synopsis: This patent discloses an optical probe designed to reduce noise in measurements taken on compressible tissue, such as a finger. The probe's construction, which may include specific chambers or materials, is intended to reduce the effects of ambient noise and motion artifacts.
  • Asserted Claims: The complaint does not specify which claims are asserted (Compl. ¶¶97-101).
  • Accused Features: The complaint alleges infringement by "Mindray Disposable Sensors" (Compl. ¶99).

III. The Accused Instrumentality

Product Identification

The accused instrumentalities are a range of patient monitoring devices and associated sensors, collectively identified as "Mindray SpO2 Products and Systems," "Mindray Reusable Sensors," and "Mindray Disposable Sensors" (Compl. ¶¶24-26). Specific product models named include the PM-50 and PM-60 Pulse Oximeters; PM-7000, PM-8000 Express, and PM-9000 Express Patient Monitors; VS-800 Vital Signs Monitor; BeneView T Series Patient Monitors; DPM SpO2 512F Adult Sensors; and DPM SpO2 520 Sensors (Compl. ¶¶24-26).

Functionality and Market Context

The complaint alleges that these products are noninvasive medical devices that incorporate "Mindray SpO2 Technology" to monitor patient physiological parameters such as blood oxygen saturation and pulse rate (Compl. ¶¶22, 24). Defendant is alleged to have imported, marketed, sold, and distributed these devices in the United States through various channels, including its website and at trade shows (Compl. ¶¶22, 23).
No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

The complaint does not contain claim charts or detailed infringement contentions that map specific product features to claim elements. The following summaries are based on the general allegations of infringement and the language of representative independent claims.

'952 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
A method for determining a true pulserate of a patient...comprising...acquiring a first measured signal...said first measured signal containing a primary portion and a secondary portion The accused products acquire a first physiological signal (e.g., from red light) containing both the desired pulse waveform and noise. ¶¶24, 58 col. 2:20-24
acquiring a second measured signal, said second measured signal containing a primary portion and a secondary portion The accused products acquire a second physiological signal (e.g., from infrared light) containing both the desired pulse waveform and noise. ¶¶24, 58 col. 2:20-24
generating a third signal, said third signal indicative of the ratio of said first measured signal to said second measured signal The internal processors of the accused products are alleged to calculate a ratio of the first and second measured signals as part of their operation. ¶¶24, 58 col. 11:25-33
processing said third signal to remove said secondary portion...said processing resulting in a fourth signal The "Mindray SpO2 Technology" within the accused products allegedly processes the signals to remove noise components, resulting in a cleaner signal for analysis. ¶¶22, 58 col. 4:20-30
determining said true pulserate from said fourth signal The accused products' processors calculate and display the patient's pulse rate based on the processed, noise-reduced signal. ¶¶24, 58 col. 4:42-47

'222 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
A signal processor for receiving a first signal having a first primary signal portion and a first secondary signal portion and a second signal having a second primary signal portion and a second secondary signal portion The processors in the accused products receive at least two distinct signals (e.g., red and infrared), each alleged to contain desired physiological data (primary portion) and noise (secondary portion). ¶¶24, 63 col. 1:11-20
said processor adapted to combine said first and second signals to generate a secondary reference having a significant component which is a function of said first and said second secondary signal portions The "Mindray SpO2 Technology" allegedly combines the two measured signals in a manner that isolates their common noise components to generate a reference signal correlated with the noise. ¶¶22, 63 col. 4:5-12
and to combine said first and second signals to generate a primary reference having a significant component which is a function of said first and second primary signal portions. The "Mindray SpO2 Technology" allegedly combines the two measured signals in a manner that isolates their common desired physiological components to generate a reference signal correlated with the desired signal. ¶¶22, 63 col. 4:13-22
  • Identified Points of Contention:
    • Evidentiary Questions: The complaint makes conclusory allegations of infringement without providing technical details about how the accused "Mindray SpO2 Technology" operates. A central point of contention will be whether Plaintiff can produce sufficient evidence to demonstrate that the accused products actually perform the specific signal processing steps required by the asserted claims.
    • Scope Questions: For the ’952 Patent, a likely dispute will be whether the accused devices perform the claimed step of "generating a third signal...indicative of the ratio" and then "processing said third signal." The analysis may turn on whether Mindray's technology uses a different mathematical approach to noise cancellation that does not meet this limitation. For the ’222 Patent, the dispute may center on whether Mindray's devices generate a "secondary reference" and "primary reference" by "combining" the signals in the manner claimed.

V. Key Claim Terms for Construction

  • The Term: "processing said third signal to remove said secondary portion" ('952 Patent, Claim 1)

  • Context and Importance: This term is central to the claimed method of the ’952 Patent. The definition of this functional step will determine what types of noise cancellation algorithms fall within the claim's scope. The dispute will likely focus on whether this language should be limited to the specific frequency-domain ratio method described in the specification or read more broadly to encompass other techniques.

  • Intrinsic Evidence for Interpretation:

    • Evidence for a Broader Interpretation: The patent abstract refers to the process as using a "signal scrubber," a general term that may support a construction covering various noise-removal techniques ('952 Patent, Abstract).
    • Evidence for a Narrower Interpretation: A disclosed embodiment describes this processing step as involving a transformation into the spectral domain, dividing signals to produce spectral ratio lines, and using the largest ratio line as a coefficient to "scrub" the waveform ('952 Patent, col. 3:37-48; Fig. 12). A defendant may argue the claim should be construed to require these specific steps.

  • The Term: "secondary reference having a significant component which is a function of said first and said second secondary signal portions" ('222 Patent, Claim 1)

  • Context and Importance: This term defines the nature of the noise reference signal used for correlation cancellation. Infringement of the ’222 Patent will depend on whether the accused devices generate a reference signal that meets this definition. Practitioners may focus on this term because the method of generating the reference signal is a core inventive concept.

  • Intrinsic Evidence for Interpretation:

    • Evidence for a Broader Interpretation: The claim uses the general phrase "function of," which could be argued to encompass any mathematical combination of the noise components from the two signals that results in a usable noise reference ('222 Patent, col. 4:5-9).
    • Evidence for a Narrower Interpretation: The specification provides a specific mathematical formula for generating the secondary reference: n'(t) = n_λa(t) - ω_a * n_λb(t), which is a weighted subtraction of one noise signal from the other ('222 Patent, col. 29:1-12; Fig. 4a). A defendant could argue that the term "combine" should be limited to this disclosed method of generation.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges that Defendant induced infringement by its customers by providing user manuals and demonstrations on how to use the accused products in an infringing manner (Compl. ¶27). It further alleges inducement of its U.S. affiliate, Mindray USA, to directly infringe by using, selling, and importing the accused products (Compl. ¶28).
  • Willful Infringement: Willfulness is alleged for all nine asserted patents (e.g., Compl. ¶59, ¶64). The basis for willfulness regarding U.S. Patent Nos. 6,002,952; 6,263,222; 6,580,086; 6,699,194; 6,745,060; and 7,215,986 is alleged pre-suit notice of infringement provided by Plaintiff to Defendant (Compl. ¶29). For the remaining patents, a willfulness claim would be predicated on knowledge acquired from the filing of the lawsuit itself.

VII. Analyst’s Conclusion: Key Questions for the Case

  • A central issue will be one of technical proof: given the complaint's conclusory allegations, can Plaintiff develop sufficient factual evidence, likely through discovery and reverse engineering, to demonstrate that the accused "Mindray SpO2 Technology" performs the specific, multi-step signal processing functions required by the asserted claims?
  • The case will also turn on claim construction: will key functional terms such as "processing said third signal" ('952 Patent) and generating a "secondary reference" ('222 Patent) be interpreted broadly to encompass a class of noise-cancellation techniques, or will they be narrowly construed and limited to the specific mathematical formulas and algorithms disclosed in the patents' specifications?
  • A third question involves damages and willfulness: did Defendant have pre-suit knowledge of infringement for at least six of the asserted patents, as alleged, and if infringement is found, would this conduct rise to the level of willfulness, potentially leading to enhanced damages?