PTAB

IPR2015-01109

Infopia Co Ltd v. Polymer Technology Systems Inc

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Method for Determining HDL Concentration From Whole Blood or Plasma
  • Brief Description: The ’397 patent discloses a method and device for determining high-density lipoprotein (HDL) cholesterol concentration from a whole blood sample. The technology utilizes a test strip with vertically stacked layers, including a red blood cell separation layer, a non-HDL separation chemistry layer, and an HDL reaction layer, designed for vertical downward fluid flow.

3. Grounds for Unpatentability

Ground 1: Obviousness over Connolly, Patel, and Kozak - Claims 1, 3-5, and 10-18 are obvious over Connolly in view of Patel, Kozak, and Steinhausen.

  • Prior Art Relied Upon: Connolly (Patent 5,597,532), Patel (Patent 5,215,886), Kozak (Patent 5,460,974), and Steinhausen (a 1985 publication on dry chemistry systems).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Connolly disclosed the core structure of the claimed invention: a test strip in a holder with vertically aligned application and reading windows, and vertically stacked layers for downward fluid flow to measure analytes, including HDL. However, Connolly did not explicitly detail a separate non-HDL separation layer. Petitioner asserted that Patel and Kozak remedied this by explicitly teaching vertically stacked test strips with distinct filter layers for removing non-HDL components (LDL and VLDL) to isolate HDL for measurement. Steinhausen was cited to show that the general principles of vertical flow dry chemistry systems for cholesterol testing were well-known.
    • Motivation to Combine: A person of ordinary skill in the art (POSITA), seeking to create a specific HDL assay using Connolly’s general device, would combine its teachings with the specific non-HDL separation layers disclosed in Patel and Kozak. All references address the same problem in the same field (blood diagnostics) using compatible technologies (layered test strips). The combination represented a predictable assembly of known elements to achieve a known result.
    • Expectation of Success: A POSITA would have a high expectation of success, as combining known separation layers (from Patel and Kozak) with a known test strip architecture (from Connolly) would predictably yield a functional HDL-specific assay.

Ground 2: Obviousness over Carroll, Patel, and Kozak - Claims 1, 3, 4, and 10-18 are obvious over Carroll in view of Patel, Kozak, and Steinhausen.

  • Prior Art Relied Upon: Carroll (Patent 6,040,195), Patel (Patent 5,215,886), Kozak (Patent 5,460,974), and Steinhausen (a 1985 publication).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground presented an alternative primary reference to Connolly. Petitioner contended that Carroll also disclosed a diagnostic test strip for analytes like HDL with all the key structural elements: vertically stacked layers (spreading, separating, reagent), a holder with aligned sample and viewing ports, and direct downward fluid flow. Similar to the argument in Ground 1, Petitioner asserted that Carroll’s general structure could be made specific for HDL measurement by incorporating the non-HDL separation layers taught by Patel and Kozak.
    • Motivation to Combine: The motivation was identical to Ground 1: a POSITA would logically incorporate the specific teachings of Patel and Kozak into the foundational test strip device of Carroll to create an effective, integrated HDL test. The references solve the same problem using interchangeable, well-understood components.
    • Expectation of Success: Success was predictable, as the combination involved integrating established filtering techniques into a known test strip format, with each component performing its intended function.

Ground 3: Obviousness of Dependent Claims over Connolly Combination - Claims 2 and 6 are obvious over Connolly, Patel, and Kozak in view of Kitajima and Kawaguri.

  • Prior Art Relied Upon: Connolly (Patent 5,597,532), Patel (Patent 5,215,886), Kozak (Patent 5,460,974), Kitajima (Patent 5,876,608), and Kawaguri (Patent 5,171,689).

  • Core Argument for this Ground:

    • Prior Art Mapping: This ground built upon the combination in Ground 1 to address limitations in dependent claims 2 and 6. Claim 2 requires separating red blood cells without an agglutinin or coagulant. Petitioner argued that Kitajima and Kawaguri explicitly taught methods for filtering blood to remove cells without causing agglutination, for example, by using an anticoagulant. Claim 6 recites impregnating the separation layer with a salt solution of a specific concentration (0.5%-3.0%). Petitioner pointed to Kitajima, which disclosed using an inorganic salt solution to accelerate the separation of blood cells from plasma.
    • Motivation to Combine: A POSITA looking to optimize the blood separation step of the primary combination (Connolly/Patel/Kozak) would have been motivated to incorporate the improved, non-clumping filtration methods from Kitajima and Kawaguri. These references provided known solutions to common problems in blood filtration for diagnostic strips.

  • Additional Grounds: Petitioner asserted additional obviousness challenges based on the primary combinations further modified by Jeng (Patent 5,064,541) for adding a wetting agent (Claim 7), Grage (Patent 5,968,765) for adding a sugar (Claim 8), and Neyer (Patent 5,762,871) for adding sorbitol (Claim 9).

4. Key Claim Construction Positions

  • Petitioner argued for a specific construction of the claim term "without substantial lateral migration of fluid below said red blood cell separation layer." This limitation was added during prosecution to overcome the Thakore reference, which involved upward capillary flow.
  • Proposed Construction: Petitioner contended the term should be construed to mean that "some fluid movement and spreading of the fluid will take place," but the primary flow path remains vertically downward. This construction was based on the patent’s own specification acknowledging that fluid movement and spreading occur in all directions within the test strip layers. The term was meant only to distinguish from primarily lateral-flow devices, not to imply a complete absence of any lateral spread.

5. Relief Requested

  • Petitioner requested institution of an inter partes review and cancellation of claims 1-18 of the ’397 patent as unpatentable under 35 U.S.C. §103.