Everstar Merchandise Co Ltd v. Willis Electric Co Ltd

1. Case Identification

• Case #: IPR2019-01485
• Patent #: 9,157,588
• Filed: August 12, 2019
• Petitioner(s): Everstar Merchandise Co. Ltd.
• Patent Owner(s): Willis Electric Co., Ltd.
• Challenged Claims: 1-20

2. Patent Overview

• Title: Decorative Lighting with Reinforced Wiring
• Brief Description: The ’588 patent discloses decorative light strings, such as for artificial Christmas trees, that use reinforced electrical wires. The wires feature an axially-extending polymer reinforcing strand, a conductor layer of copper conductors adjacent to the strand, and an outer insulating layer.

3. Grounds for Unpatentability

Ground 1: Obviousness over Harris and Fujii - Claims 1-3 and 6 are obvious over Harris in view of Fujii (and optionally in view of the UL Standards).

• Prior Art Relied Upon: Harris (Patent 1,656,148), Fujii (Patent 5,216,205), and UL Standards (UL 588, 18th Ed., Feb. 2002).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Harris disclosed the fundamental structure of a decorative light string for an artificial Christmas tree, including a plurality of lamp assemblies, power wires, and connection to an electrical power source, as required by independent claim 1. However, Harris did not explicitly teach reinforced wiring. Petitioner asserted that Fujii remedied this deficiency by disclosing a high-strength wire conductor with all the structural elements of the claimed reinforced wire: an aramid fiber bundle (an axially-extending polymer reinforcing strand), a plurality of surrounding copper strands (a conductor layer), and an outer insulating coat.
  • Motivation to Combine: Petitioner contended a person of ordinary skill in the art (POSITA) would combine Harris and Fujii to improve the durability of decorative light strings. The modification was argued to be a simple substitution of a known element (Fujii's strong wire) for an existing one (Harris's conventional wire) to achieve the predictable result of a more robust and break-resistant light string suitable for seasonal use. The UL Standards were cited as further evidence that a POSITA would have considered using polymeric supporting ropes for durability.
  • Expectation of Success: A POSITA would have had a clear expectation of success because combining the references involved using a known technique—substituting a stronger wire—to improve a known device, yielding predictable improvements in strength and durability.

Ground 2: Obviousness over Lin and Fujii - Claims 7-10, 12, 14, 15, and 17-18 are obvious over Lin modified by Fujii (and optionally in view of the UL Standards).

• Prior Art Relied Upon: Lin (Application # 2007/0159822), Fujii (Patent 5,216,205), and UL Standards (UL 588, 18th Ed., Feb. 2002).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner asserted that Lin taught a conventional decorative lamp string with the core components recited in independent claim 7: a plurality of lamp assemblies connected by light-connecting wires and powered by first and second power wires connected to a plug. Similar to the argument in Ground 1, Petitioner argued that Lin's conventional wires could be replaced with the reinforced wire taught by Fujii, which disclosed the claimed reinforcing strand, conductor layer, and insulating layer.
  • Motivation to Combine: The motivation was analogous to Ground 1. A POSITA seeking to solve the problem of insufficient wire strength in decorative lighting would have been motivated to replace the standard wires in Lin's light string with the high-tensile-strength wire from Fujii. This combination would predictably result in a more durable product, addressing a known issue in the field of seasonal lighting.
  • Expectation of Success: The argument mirrored that of Ground 1, stating that incorporating Fujii's wire into Lin's light string was a straightforward application of a known solution to a known problem, with a high likelihood of achieving the desired increase in durability.

Ground 3: Obviousness over Lin and Huang - Claims 7-8, 10-14, and 19-20 are obvious over Lin in view of Huang (and optionally in view of the UL Standards).

• Prior Art Relied Upon: Lin (Application # 2007/0159822) and Huang (Application # 2013/0062095).

• Core Argument for this Ground:

  • Prior Art Mapping: This ground again used Lin as the primary reference for the basic decorative light string structure of claim 7. As a substitute for Fujii, Petitioner relied on Huang to teach the specific reinforced wire structure. Huang disclosed a wire with a central reinforcing filament made of a polymer tensile fiber (e.g., PET), plural copper conductors spirally wound around the filament, and an outer insulation layer, thereby teaching all elements of the claimed reinforced wire.
  • Motivation to Combine: Petitioner argued that a POSITA would combine Lin and Huang to increase the wire's resistance to tension and improve overall durability. Huang explicitly taught that its reinforcing filament was effective for this purpose. The combination was presented as a predictable solution to the known problem of wire fragility in decorative light strings.
  • Expectation of Success: A POSITA would expect success in this combination, as it involved substituting one type of electrical wire for another improved type to enhance a well-understood physical property (tensile strength) in a conventional product (a light string).

• Additional Grounds: Petitioner asserted additional obviousness challenges, including combinations incorporating Bowden (Patent 3,831,132) for crimped terminals, Debladis (Patent 8,692,120) for multiple reinforcing strands, Wlos (Application # 2004/0222012) for multiple conductor layers, and Pacini (Patent 3,214,579) for lighted tree conductors.

4. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under 35 U.S.C. §325(d) would be improper. It contended that the core prior art references central to its petition—including Fujii, Huang, Debladis, Wlos, Bowden, and Lin—were never cited or considered during the original prosecution of the ’588 patent. Furthermore, while Harris and Pacini were cited during prosecution, they were never applied or discussed by the Examiner.

5. Relief Requested

• Petitioner requests institution of an inter partes review and cancellation of claims 1-20 of Patent 9,157,588 as unpatentable.