Clear-Vu Lighting LLC v. University of Strathclyde

1. Case Identification

• Case #: Unassigned
• Patent #: 8,398,264
• Filed: February 27, 2019
• Petitioner(s): CLEAR-VU LIGHTING LLC
• Patent Owner(s): University of Strathclyde, Kenall Manufacturing Company (Licensee)
• Challenged Claims: 1-30

2. Patent Overview

• Title: LIGHTING DEVICE
• Brief Description: The ’264 patent is directed to a lighting device for inactivating pathogenic bacteria, such as methicillin-resistant Staphylococcus aureus, by exposing them to visible light. The device includes a first light element for bactericidal effect and a second light element, which may provide white light, to reduce disturbing effects on individuals exposed to the bactericidal light.

3. Grounds for Unpatentability

Ground A: Claims 1-3, 5, 7-11, 14-21, 25-26, and 28-29 are obvious over Powell in view of Altshuler and the Lighting Handbook.

• Prior Art Relied Upon: Powell (Application # 2006/0030908), Altshuler (Application # 2007/0239143), and Lighting Handbook (Eighth Ed., 1993).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Powell discloses a desk lamp (a "lighting device") with two light sources: a wavelength-specific light for treating acne and a general-purpose white light. This maps to the claimed first and second elements. While Powell teaches using blue light (400-470 nm) to kill acne-causing bacteria, it does not specify the required irradiance. Altshuler, in the same field, supplies this missing element by teaching that 405 nm blue light at an irradiance of at least 0.01 W/cm² is sufficient to kill acne-causing bacteria. To meet the "higher illuminance" limitation of claim 1, Petitioner asserted a POSITA would consult the Lighting Handbook, which recommends illuminance levels of 200-2,000 lx for desk tasks, an illuminance higher than the calculated illuminance (approx. 425 lx) of the bactericidal blue light described by Altshuler.
  • Motivation to Combine: A POSITA would be motivated to combine Powell and Altshuler to create an effective, predictable phototherapeutic desk lamp. The combination involves using Altshuler's specific, effective irradiance and wavelength to optimize the general device taught by Powell. A POSITA would then consult a standard reference like the Lighting Handbook to ensure the device's general lighting function was suitable for its intended purpose (e.g., reading), a routine design consideration.
  • Expectation of Success: A POSITA would have a high expectation of success. Altshuler's taught wavelength (405 nm) falls squarely within the bactericidal range disclosed by Powell (400-470 nm), and Altshuler explains the known biological mechanism of action (light absorption by porphyrins in bacteria), confirming the combination's predictable outcome.

Ground G: Claims 1-7, 9-11, 13-21, 25-26, and 28-30 are obvious over Chung in view of Altshuler.

• Prior Art Relied Upon: Chung (WO 2004/033028) and Altshuler (Application # 2007/0239143).

• Core Argument for this Ground:

  • Prior Art Mapping: Petitioner contended that Chung teaches a phototherapeutic device for treating conditions like acne that uses two different colors of light: a "treatment color" (e.g., blue) and a "balancing color" (e.g., yellow) to mitigate discomfort for the user. This provides the claimed first and second light elements. Like Powell, Chung does not specify a bactericidal irradiance. Altshuler again supplies the missing teaching, disclosing that 405 nm light at a sufficient irradiance kills acne bacteria. Petitioner also argued that Chung's teaching of balancing blue and yellow light of "equal intensity" (interpreted as radiant intensity) would result in the yellow light having a significantly higher illuminance, thereby meeting the limitation of claim 1.
  • Motivation to Combine: A POSITA would be motivated to modify Chung's phototherapy device by incorporating Altshuler's teachings to ensure a therapeutically effective bactericidal output. This represents a straightforward combination of a general system (Chung) with specific, performance-enhancing parameters (Altshuler) from the same field of art to achieve a known goal (effective acne treatment).
  • Expectation of Success: Success would be expected because both references address phototherapy for acne. Applying Altshuler’s specific wavelength and irradiance to Chung's device is a predictable optimization. Chung explicitly teaches that combining the treatment and balancing colors can produce the perception of white light, meeting another key claim element.

• Additional Grounds: Petitioner asserted numerous additional obviousness challenges to address specific dependent claims by adding single, well-known elements to the primary combinations. These included adding Jones (Application # 2005/0055070) for a lens, Pederson (Patent 6,875,225) for a diffuser, Maxik ’152 (Application # 2005/0207152) for motion sensors, and Maxik ’159 (Application # 2005/0207159) for wall or roof mounting.

4. Key Claim Construction Positions

• "inactivate": Petitioner asserted this term has a defined meaning in the specification: "bacteria are killed, or damaged so as to reduce or inhibit bacterial replication."
• Means-Plus-Function Claims: Petitioner argued that claims 21, 25, and 26 invoke §112, sixth paragraph.
  • For "means for switching" (claims 21, 26), Petitioner identified the corresponding structure as a simple switch and the corresponding acts as detecting a person, movement, environmental changes, or occupancy, and boosting between irradiance modes.
  • For "means for varying" (claim 25), Petitioner identified the same structure and acts as for the "means for switching."

5. Key Technical Contentions (Beyond Claim Construction)

• Irradiance vs. Illuminance: A central technical argument, supported by an expert declaration (Dr. Coleman), was the conversion between radiometric units (irradiance, W/cm²) and photometric units (illuminance, lx). Petitioner argued that to prove the second element has a "higher illuminance" than the first, a POSITA could and would perform these standard calculations. The petition provided detailed calculations showing that for the same irradiance, yellow light (the "second element" in the Chung combination) has a much higher illuminance than blue light (the "first element") due to the luminosity function of the human eye. This technical point was crucial to mapping prior art to the limitations of independent claim 1.

6. Arguments Regarding Discretionary Denial

• Petitioner implicitly argued against discretionary denial under §325(d) by noting that the primary prior art references, Powell, Altshuler, Chung, and the Lighting Handbook, were not cited during the original prosecution. It was further noted that while other references (Jones and Maxik '159) were of record, they were never applied in any art-based rejection by the examiner. This suggests that the PTAB would be considering the key prior art and arguments for the first time.

7. Relief Requested

• Petitioner requests institution of an inter partes review and cancellation of claims 1-30 of the '264 patent as unpatentable.