United Industries Corp v. Susan McKnight Inc

1. Case Identification

• Case #: IPR2017-01686
• Patent #: 9,253,973
• Filed: June 30, 2017
• Petitioner(s): United Industries Corporation
• Patent Owner(s): Susan McKnight, Inc.
• Challenged Claims: 1-17

2. Patent Overview

• Title: Crawling Arthropod Intercepting Device and Method
• Brief Description: The ’973 patent discloses a dual-receptacle (pitfall) insect trap designed for placement under furniture legs to intercept bed bugs. The device features an exterior surface that is rough to allow insects to climb it, and interior surfaces that are "slippery" to prevent trapped insects from escaping.

3. Grounds for Unpatentability

Ground I: Claims 1-17 are obvious over Jennerich in view of Lyng and Jennings.

• Prior Art Relied Upon: Jennerich (Patent 2,167,978), Lyng (Application # 2005/0138858), and Jennings (Patent 400,460).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Jennerich disclosed the core structural elements of the challenged claims, including a dual-receptacle insect trap with an exterior climbable surface and inner and outer pitfall traps. Jennerich achieved a slippery surface via a "paralyzing powder" (talcum). Petitioner contended that Lyng and Jennings explicitly taught the key missing element: using materials that are inherently slippery to prevent insect escape. Lyng described an insect trap with a "smooth and slippery surface" made from materials like polymers (polyethylene, polypropylene) or polished metal to provide "no footing for an insect." Jennings similarly taught using a "polished material" to cause insects to lose their footing.
  • Motivation to Combine: A POSITA would combine the teachings of Lyng and Jennings with Jennerich to improve the trap's fundamental function—preventing escape. Replacing Jennerich's powder with an inherently slippery surface as taught by Lyng and Jennings was presented as an obvious design choice to create a more effective and reliable trap, leveraging known materials for their well-understood properties. Lyng's teachings on the low cost and ease of manufacturing with polymers provided an additional economic motivation.
  • Expectation of Success: A POSITA would have a high expectation of success, as using smooth surfaces to prevent insects from climbing was a long-established and predictable principle in the art of insect trap design.

Ground II: Claims 1-3, 7, 10, 14, 16-17 are obvious over Anderson in view of Dempster and Lang.

• Prior Art Relied Upon: Anderson (Patent 5,996,531), Dempster (Patent 1,024,767), and Lang (Application # 2007/0044372).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner asserted that Anderson disclosed a protective pet dish with a dual-receptacle moat structure placed under container legs to trap insects, teaching the claimed inner and outer pitfall traps. To the extent Anderson's surfaces were not sufficiently climbable or slippery, Dempster and Lang supplied these features. Dempster taught an insect trap with "roughened outer surfaces" to facilitate climbing and "smooth inner faces" to prevent escape. Lang taught that texturing exterior surfaces on bed bug traps is preferable to help bugs crawl into the trap.
  • Motivation to Combine: A POSITA would combine these references to improve the efficacy of Anderson's insect-trapping device. Specifically, a POSITA would be motivated to incorporate the roughened exterior from Dempster or Lang to ensure insects could enter the trap, and the smooth interior from Dempster to ensure they could not escape. This combination represented the application of known techniques to solve a known problem.
  • Expectation of Success: The result of the combination was predictable. Making an exterior surface rougher and an interior surface smoother would predictably improve insect capture rates, which was a simple and well-understood design principle.

Ground III: Claims 1-17 are obvious over Denton in view of Jennerich and McKnight.

• Prior Art Relied Upon: Denton (Patent 223,321), Jennerich (Patent 2,167,978), and McKnight (Patent 8,966,812).

• Core Argument for this Ground:

  • Prior Art Mapping: Petitioner argued that Denton, from 1880, disclosed a basic dual-receptacle "vermin trap" for use with furniture legs, made of materials like earthenware or porcelain, which are inherently smooth. The combination addressed any potential deficiencies in Denton's disclosure. Jennerich taught an exterior surface that is sloped and roughened to be climbable. McKnight explicitly taught a "climb-up pitfall trap for bed bugs" with a rough exterior for climbing and an interior surface that is slippery to prevent escape.
  • Motivation to Combine: A POSITA would combine the teachings of Jennerich and McKnight with Denton to modernize and improve the functionality of the basic trap design. This involved incorporating a purpose-built rough exterior surface for climbing and ensuring the interior surfaces were sufficiently slippery, both of which were well-known improvements in the art for enhancing trap effectiveness.
  • Expectation of Success: A POSITA would have a reasonable expectation of success in applying these established principles to the Denton design to create a more effective trap, as the outcome was merely the sum of the predictable functions of the combined elements.

• Additional Grounds: Petitioner asserted additional obviousness challenges, including combinations based on Anderson in view of Dempster, Lang, and Lyng (Ground III); Anderson in view of Dempster, Lang, and Metcalfe (Ground IV); and McGrath in view of Lyng (Ground VI), all relying on similar theories of combining a basic trap structure with prior art teaching specific surface textures for climbing or preventing escape.

4. Key Claim Construction Positions

• Petitioner argued the term "slippery" is indefinite because its meaning is purely functional ("slippery to prevent bed bugs from climbing out") and depends on variable external factors (e.g., size and vitality of the bugs).
• For the purposes of the petition, and because indefiniteness cannot be adjudicated in an inter partes review (IPR), Petitioner construed "slippery" to mean "smooth," based on the specification's examples of "slippery material[s]" such as "polymer, glass, or polished metallic material."

5. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under §325(d) would be inappropriate, even though the primary reference (Jennerich) was considered during prosecution. Petitioner asserted that the Examiner's basis for allowance directly contradicted the Examiner's own earlier findings, which the Patent Trial and Appeal Board had previously affirmed. Petitioner contended that instituting the IPR was in the interest of "correcting any errors by the Office in allowing a patent."

6. Relief Requested

• Petitioner requested institution of an IPR trial and cancellation of claims 1-17 of the ’973 patent as unpatentable under 35 U.S.C. §103.