DCT

2:18-cv-01352

Kenall Mfg Co v. Oldenburg Group Inc

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 2:18-cv-01352, E.D. Wis., 08/31/2018
  • Venue Allegations: Venue is alleged to be proper based on Defendant having its principal place of business and a regular and established place of business within the Eastern District of Wisconsin, where it has allegedly committed acts of infringement.
  • Core Dispute: Plaintiffs allege that Defendant’s line of disinfecting lighting fixtures infringes three patents related to methods and systems for inactivating bacteria using specific wavelengths of visible light.
  • Technical Context: The technology concerns the use of narrow-spectrum visible light, particularly near 405 nm, to provide continuous environmental disinfection in occupied spaces, such as hospitals, without the use of chemical agents or harmful UV radiation.
  • Key Procedural History: The complaint alleges that Plaintiffs provided Defendant with notice of infringement on June 22, 2018. U.S. Patent No. 9,839,706 is a continuation of the application that resulted in U.S. Patent No. 9,039,966 and includes a terminal disclaimer. Subsequent to the complaint filing, an Inter Partes Review (IPR) was initiated against the ’706 Patent (IPR2019-00431); the proceeding concluded with a certificate issued on August 18, 2022, confirming the patentability of claims 1-4, which includes the claims asserted in this litigation.

Case Timeline

Date Event
2005-07-29 Priority Date for ’966 and ’706 Patents
2007-10-31 Priority Date for ’264 Patent
2013-03-19 ’264 Patent Issued
2015-05-26 ’966 Patent Issued
2017-12-12 ’706 Patent Issued
2018-06-22 Alleged Notice of Infringement Sent to Defendant
2018-08-31 Complaint Filed
2018-12-12 Inter Partes Review (IPR) Filed Against ’706 Patent
2022-08-18 IPR Certificate Issued Confirming Patentability of ’706 Patent Claims 1-4

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

U.S. Patent No. 9,039,966 - "Inactivation of Gram-Positive Bacteria"

  • Issued: May 26, 2015

The Invention Explained

  • Problem Addressed: The patent describes prior art methods for destroying bacteria using light as requiring the use of photosensitizing agents, which presented a "significant limitation" for techniques seeking to decontaminate living tissue or environmental surfaces (Compl. ¶11; ’966 Patent, col. 2:1-10).
  • The Patented Solution: The invention provides a method for disinfecting surfaces and air by exposing bacteria, such as MRSA, to a narrow band of visible light (400-420 nm) without using a photosensitizer. The method is specified for use on non-living surfaces and requires that the target area is not exposed to a "disinfecting dose" of light at wavelengths above 500 nm, thereby focusing the antimicrobial effect on a specific part of the spectrum (’966 Patent, Abstract; col. 6:62-7:7).
  • Technical Importance: This approach enables environmental disinfection to occur continuously and safely in the presence of people, a significant advantage over methods like UV radiation or chemical fumigation that require spaces to be vacated (Compl. ¶14).

Key Claims at a Glance

  • The complaint asserts independent claim 1 (Compl. ¶21).
  • Essential elements of claim 1:
    • A method for disinfecting air, contact surfaces, or materials by inactivating MRSA.
    • The method comprises exposing MRSA to visible light without using a photosensitizer.
    • The visible light for inactivation "consists of" wavelengths in the 400-420 nm range.
    • The method is performed outside a human body on non-living surfaces/materials.
    • The air, surfaces, or materials are not exposed to a "disinfecting dose" of light at a wavelength above 500 nm.
  • The complaint does not explicitly reserve the right to assert dependent claims.

U.S. Patent No. 9,839,706 - "Inactivation of Gram-Positive Bacteria"

  • Issued: December 12, 2017

The Invention Explained

  • Problem Addressed: As with its parent patent, the ’706 Patent addresses the limitations of prior art light-based disinfection methods that required photosensitizing agents to be effective (’706 Patent, col. 2:1-19).
  • The Patented Solution: The invention claims a method and a system for inactivating a specified list of pathogenic Gram-positive bacteria. The solution uses visible light where "a portion" of that light consists of wavelengths between 400-420 nm. This is distinct from the ’966 Patent in its description of the light spectrum and the broader group of targeted bacteria (’706 Patent, Abstract; col. 8:1-25).
  • Technical Importance: The technology provides a framework for both a method and a physical system capable of disinfecting environments from a range of common pathogens without requiring chemical agents or creating hazardous conditions for humans (Compl. ¶14).

Key Claims at a Glance

  • The complaint asserts independent claim 1 (a method claim) and independent claim 3 (a system claim) (Compl. ¶¶ 29, 36).
  • Essential elements of claim 1:
    • A method for disinfecting by inactivating one or more pathogenic Gram-positive bacteria selected from a specific group (MRSA, CONS, Streptococcus, etc.).
    • The method comprises exposing the bacteria to visible light without a photosensitizer.
    • "a portion of the visible light that inactivates" the bacteria "consists of" wavelengths in the 400-420 nm range.
    • The method is performed outside a human body on non-living surfaces/materials.
  • Essential elements of claim 3:
    • A system for disinfecting by inactivating one or more pathogenic Gram-positive bacteria from a specific group.
    • The system comprises "means for exposing said bacteria to visible light without using a photosensitizer."
    • "a portion of the visible light that inactivates" the bacteria "consists of" wavelengths in the 400-420 nm range.
    • The system is for use outside the human body on non-living surfaces/materials.
  • The complaint does not explicitly reserve the right to assert dependent claims.

U.S. Patent No. 8,398,264 - "Lighting Device"

  • Issued: March 19, 2013 (Compl. ¶8)

Technology Synopsis

  • This patent discloses a lighting device comprising at least two different light-emitting elements. A first element emits light in a narrow, bactericidal wavelength (e.g., 405 nm), while a second element emits light at longer wavelengths to provide ambient illumination. The key inventive concept is that the second element has a higher illuminance (perceived brightness) than the first, creating a combined light output that is effective for disinfection but comfortable for human eyes (’264 Patent, Abstract; col. 2:44-55).

Asserted Claims & Accused Features

  • Asserted Claims: The complaint asserts independent claims 1 and 30 (Compl. ¶¶ 43, 47).
  • Accused Features: The accused products are alleged to be lighting devices that embody this dual-element design. The complaint specifically points to the products' "HDS Eco Mode" and "White Light Disinfection" mode as evidence of a first element for disinfection and a second for ambient illumination (Compl. ¶¶ 46, 50).

III. The Accused Instrumentality

Product Identification

  • The "Symmetry," "Jasper," "Cade," "Cantena," and "Latitude" light fixtures, among other similar products (collectively "Accused Products") (Compl. ¶17).

Functionality and Market Context

  • The Accused Products are marketed as lighting fixtures that both provide illumination and kill harmful germs in environments such as hospitals (Compl. ¶19). The complaint alleges they operate by emitting "safe, germicidal wavelengths from true white light," specifically referencing the use of "400-405 nm wave lengths" to inactivate bacteria, including MRSA (Compl. ¶¶ 23, 26). The complaint includes a marketing diagram showing the germicidal effect is concentrated at 405 nm, which is described as "safe for humans" (Compl. ¶26, p. 7). The products are alleged to feature at least two operational modes: "HDS (Eco Mode)" for high-intensity disinfection when full illumination is not needed, and "White Light Disinfection" mode, which provides continuous disinfection along with ambient light (Compl. ¶27). A visual from Defendant's literature contrasts these two modes, showing one with prominent blue/violet light and the other with standard white light (Compl. ¶46, p. 12).

IV. Analysis of Infringement Allegations

’966 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
A method for disinfecting...by inactivating methicillin-resistant Staphylococcus aureus (MRSA)... The Accused Products are used to disinfect surfaces by killing or inactivating bacteria, including MRSA. ¶23 col. 2:41-47
said method comprising exposing the MRSA to visible light without using a photosensitiser... The Accused Products expose MRSA to visible light and do not use a photosensitizer. ¶25 col. 2:13-15
wherein the visible light for inactivating the MRSA consists of wavelengths in the range of 400-420 nm... Defendant's marketing materials describe the products as using "400-405 nm wave lengths" to kill harmful microorganisms. ¶26 col. 2:48-52
and wherein the method is performed outside of a human body, the contact surfaces or the materials are non-living... The Accused Products are marketed for disinfecting non-living surfaces such as "surgical instruments and floors." ¶23 col. 1:19-22
and the air, contact surfaces or materials are not exposed to a disinfecting dose of light at a wavelength above 500 nm. Based "on information and belief," the Accused Products do not expose materials to a disinfecting dose of light above 500 nm. ¶28 col. 4:50-65

Identified Points of Contention

  • Scope Questions: A central dispute may arise from the term "consists of." The accused product is described as emitting "true white light" (Compl. ¶23), which is a broad spectrum. The claim, however, requires the inactivating light to "consist of" only wavelengths in the 400-420 nm range. This raises the question of whether a product emitting a broader spectrum that includes these wavelengths can infringe a claim with such a restrictive transition phrase.
  • Technical Questions: The complaint's allegation for the negative limitation ("not exposed to a disinfecting dose of light at a wavelength above 500 nm") is made "on information and belief" (Compl. ¶28). The case may turn on factual evidence of the accused product's full spectral output and expert testimony defining what constitutes a "disinfecting dose" at different wavelengths.

’706 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
A method for disinfecting...by inactivating one or more pathogenic Gram-positive bacteria...selected from the group consisting of Methicillin-resistant Staphylococcus aureus (MRSA)... The Accused Products are touted to kill "gram negative and gram positive bacteria [including] Staphylococcus aureus (incl. MRSA)." ¶32 col. 2:30-36
said method comprising exposing the one or more pathogenic Gram-positive bacteria to visible light without using a photosensitizer... The Accused Products expose bacteria to visible light and do not use a photosensitizer. ¶33 col. 2:19-21
wherein a portion of the visible light that inactivates the one or more pathogenic Gram-positive bacteria consists of wavelengths in the range 400-420 nm... Defendant's marketing materials state the products use "400-405 nm wave lengths." The complaint includes a spectrum diagram from Defendant's materials to support this. ¶34 col. 2:62-65
and wherein the method is performed outside of the human body and the contact surfaces or the materials are non-living. The products are described as a source for disinfecting non-living surfaces such as "surgical instruments and floors." ¶31 col. 1:24-26

Identified Points of Contention

  • Scope Questions: Claim 3 recites a "means for exposing said bacteria to visible light." This is a means-plus-function limitation under 35 U.S.C. § 112(f). Infringement will require a showing that the structure in the accused device that performs this function is the same as or equivalent to the corresponding structure described in the patent's specification (e.g., a Xenon lamp or an LED array) (’706 Patent, col. 4:1-12).
  • Technical Questions: The phrase "a portion of the visible light...consists of" is different from the language in the ’966 Patent. The interpretation of this phrase will be critical. It raises the question of whether this language is met if the germicidal wavelengths are merely one component of a broader spectrum (e.g., white light), or if it requires a discrete, separable "portion" of light that is composed only of those wavelengths.

V. Key Claim Terms for Construction

The Term: "a portion of the visible light...consists of" (’706 Patent, Claim 1)

  • Context and Importance: This term's construction is likely the most critical issue in the case, as it directly addresses the potential mismatch between the patents' narrow wavelength focus and the accused "true white light" products. Its interpretation relative to the stricter "consists of" language in the ’966 Patent will define the scope of infringement for the ’706 Patent.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: A party could argue "a portion" implies that the claimed 400-420 nm light is just one component of a larger whole (the total visible light), making it compatible with a white light source. The specification’s general discussion of using "blue light, or white light containing blue light" could support this view (’706 Patent, col. 2:40-41).
    • Evidence for a Narrower Interpretation: A party could argue that "consists of" still acts as a hard limit, meaning that the "portion" itself must be composed only of the recited wavelengths, even if other light is also present. The patent's focus on the "optimal inactivation at 405 nm" and the detailed experiments using narrow bandpass filters could be used to argue that the invention is specific to this narrow range, not just a component within a broad spectrum (’706 Patent, col. 2:64-65).

The Term: "disinfecting dose" (’966 Patent, Claim 1)

  • Context and Importance: This term is part of a negative limitation ("not exposed to a disinfecting dose of light at a wavelength above 500 nm"). The infringement analysis for the ’966 patent depends entirely on whether the accused products' light output above 500 nm meets the court's definition of a "disinfecting dose."
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: A party might argue for a high threshold, suggesting a "disinfecting dose" implies a level of energy sufficient to achieve a specific, high log reduction of bacteria on its own, a standard the ambient white light component of the accused product may not meet.
    • Evidence for a Narrower Interpretation: The patent itself provides dose values (in J/cm²) that achieved certain levels of inactivation, but does not formally define the term (’966 Patent, Table on col. 5). A party could argue that any statistically significant bactericidal effect constitutes a "disinfecting dose," potentially bringing the accused white light within the scope of this negative limitation and leading to a finding of non-infringement.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges both induced and contributory infringement for all three patents. The allegations are based on Defendant’s creation and distribution of "promotional and instructional literature" that allegedly encourages and instructs customers on how to use the Accused Products in an infringing manner. The complaint further alleges the products have "no substantial, non-infringing use" (Compl. ¶¶ 61, 75, 89).
  • Willful Infringement: Willfulness is alleged for all three patents. The claim is based on Defendant’s alleged knowledge of the patents, grounded in a notice letter Plaintiffs claim to have sent on or before June 22, 2018, more than two months before the complaint was filed (Compl. ¶¶ 55, 60, 74, 88).

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

  • A core issue will be one of claim scope: can the restrictive term "consists of" in the ’966 patent be read to cover a "true white light" product, or is infringement precluded? And how will the court’s interpretation of the arguably less restrictive phrase "a portion...consists of" in the ’706 patent affect the outcome for that patent?
  • A key evidentiary question will be one of technical fact: do the accused products emit a "disinfecting dose" of light at wavelengths above 500 nm? The resolution of this issue, which hinges on the court's construction of "disinfecting dose" and detailed technical evidence about the products' spectral output, will be determinative for infringement of the ’966 patent.
  • A central question for the ’706 system claim will be the application of means-plus-function claiming: will the court find that the light-emitting structures in the accused fixtures are structurally equivalent to the specific lamp and LED configurations disclosed in the patent specification?