PTAB

IPR2017-00335

Willis Electric Co Ltd v. Polygroup Macau Ltd BVI

Log In
Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Artificial Tree Construction
  • Brief Description: The ’810 patent discloses a power transfer system for an artificial tree that allows trunk sections to be connected without requiring specific rotational alignment. The invention features male and female connectors with corresponding central and channel prongs/voids, where the female connector utilizes spring-activated contact sections to ensure a secure electrical connection upon assembly.

3. Grounds for Unpatentability

Ground 1: Claims 1-10 are obvious over Chen in view of McLeish.

  • Prior Art Relied Upon: Chen (Patent 8,454,186) and McLeish (Patent 7,066,739).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Chen discloses nearly all elements of the challenged claims, including an artificial tree with stackable trunk sections and coaxial electrical connectors that permit connection at any rotational orientation. Chen's connector has a male end with a central prong and a surrounding channel prong, and a female end with corresponding voids. However, Petitioner contended that Chen does not explicitly disclose that its contact devices use spring-activated sections. McLeish was introduced to supply this teaching, as it discloses electrical connectors with spring-loaded terminals, including a "spring contact finger" in a central void, designed to maintain a reliable connection.
    • Motivation to Combine: A POSITA would combine the teachings of Chen and McLeish to improve the reliability and durability of the electrical connection in an artificial tree. Petitioner asserted that Chen itself suggests its contacts could be interchanged with other known electrical terminals, providing a direct reason to incorporate the well-known spring-activated contacts from a reference like McLeish to prevent arcing and ensure a secure connection in a product meant for repeated assembly.
    • Expectation of Success: A POSITA would have a high expectation of success, as the combination involved substituting a known type of contact (spring-activated) into an existing coaxial connector system to achieve the predictable result of a more stable electrical connection.

Ground 2: Claims 1-10 are obvious over Chen in view of McLeish and Geisthoff.

  • Prior Art Relied Upon: Chen (Patent 8,454,186), McLeish (Patent 7,066,739), and Geisthoff (Patent 4,437,782).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground incorporated the arguments from Ground 1 and added Geisthoff to address dependent claim 8, which requires radially extending clutch elements to prevent rotation. While Chen’s primary embodiment allows for 360-degree rotational connection, Geisthoff teaches mechanical structures, such as splines on a shaft engaging a hub, that provide torque-transmitting engagement and prevent free rotation between connected parts.
    • Motivation to Combine: Petitioner argued that a POSITA would be motivated to add an anti-rotation feature to Chen's design for user convenience. While electrical connection could be made at any angle, preventing the trunk sections from spinning after assembly would be a desirable improvement to keep decorations aligned. Chen’s disclosure of alternative, non-circular mechanical shapes for "minimal rotational alignment" would have prompted a POSITA to look to known anti-rotation solutions like the splines taught by Geisthoff.

Ground 3: Claims 1-6, 9 are obvious over Otto in view of Ordinary Knowledge.

  • Prior Art Relied Upon: Otto (German Utility Model DE 8436328).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner asserted Otto discloses a lighted artificial tree with modular trunk sections connected by a coaxial plug-and-socket system. The male plug has a central prong and a coaxial sleeve-shaped prong, while the female socket has corresponding central and channel voids (bushings). Otto expressly teaches that the channel bushing has "inwardly facing elastic elements" to ensure a firm connection, which Petitioner argued meets the "spring-activated-contact" limitation. The ground contended that applying this same known principle to the central contact was an obvious modification.
    • Motivation to Combine (with POSA knowledge): A POSITA, knowing that electrical connections can become unreliable with repeated use, would be motivated to ensure a stable connection for both the central and channel contacts. Since Otto already applied elastic elements to the channel contact, it would have been an obvious design choice to incorporate a similar, well-known spring-activated contact (e.g., a fork-like terminal or spring finger) into the central bushing to achieve the same predictable benefit of a more reliable connection.

4. Key Claim Construction Positions

  • "channel prong": Petitioner proposed the construction "an electrically conductive protrusion radially offset from the central prong." A key point of contention was that the Patent Owner, during prosecution, acted as its own lexicographer to broaden the term to include tubular structures not resembling a traditional "prong." Petitioner argued this construction was not enabled by the provisional application.
  • "contact device comprising one or more spring-activated-contact sections": Petitioner proposed "conductive component with one or more areas utilizing elastic contact sections for maintaining radial pressure between contacts." Similar to "channel prong," Petitioner argued this feature was not disclosed in the provisional application.

5. Key Technical Contentions (Beyond Claim Construction)

  • Priority Date Challenge: A central contention woven throughout the petition was that the ’810 patent was not entitled to its claimed provisional priority date of October 28, 2011. Petitioner argued that key claim limitations, including the specific structures for the "channel prong" and "spring-activated-contact sections," lacked written description and enabling support in the provisional application. Therefore, Petitioner asserted the correct priority date for the challenged claims was the later non-provisional filing date of October 24, 2012, which would make additional prior art available.

6. Relief Requested

  • Petitioner requested the institution of an inter partes review and the cancellation of claims 1-10 of the ’810 patent as unpatentable.