DCT

4:17-cv-01906

Water Technology LLC v. Kokido Development Ltd

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Key Events
Complaint

I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 4:17-cv-01906, E.D. Mo., 06/30/2017
  • Venue Allegations: Venue for Kokido, a foreign company, is alleged to be proper as it is subject to personal jurisdiction in the district. Venue for Menard, Inc. is alleged to be proper because it is a domestic corporation that has committed acts of infringement in the district and maintains a regular and established place of business there.
  • Core Dispute: Plaintiff alleges that Defendants’ hand-held, battery-powered pool vacuums infringe five of its utility and design patents related to submersible pool cleaner technology.
  • Technical Context: The technology concerns self-contained, hand-held, battery-powered pool cleaners, which created a market for portable devices that do not require cumbersome external power cords or vacuum hoses.
  • Key Procedural History: The complaint alleges a prior commercial relationship between the parties, where Plaintiff manufactured a product for Defendant Kokido to sell outside the U.S. This product was allegedly marked with the asserted patent numbers, forming a basis for pre-suit knowledge. Plaintiff also alleges it sent a notice letter to Kokido detailing its patent rights prior to filing the lawsuit.

Case Timeline

Date Event
2002-10-29 Priority Date for ’460 and ’182 Patents
2005-09-06 U.S. Patent No. 6,939,460 Issues
2006-06-13 U.S. Patent No. 7,060,182 Issues
2006-11-09 Priority Date for ’D396 Design Patent
2007-11-27 U.S. Design Patent No. D556,396 Issues
2008-05-15 Priority Date for ’975 Patent
2009-12-29 U.S. Patent No. 7,636,975 Issues
2011-05-16 Priority Date for ’441 Patent
2012-10-09 U.S. Patent No. 8,281,441 Issues
2013-01-01* Plaintiff begins manufacturing "Vektro" product for Kokido (circa)
2015-01-01* Kokido allegedly begins selling infringing products (circa)
2015-08-12 Plaintiff sends notice letter to Kokido
2015-12-01 Kokido responds to notice letter
2016-08-08 Menards notifies Plaintiff it will stop purchasing its products
2017-03-01* Menards begins selling accused Kokido products (circa)
2017-04-08 Kokido allegedly imports infringing products for Menards
2017-06-30 Complaint Filed

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 6,939,460 - "Portable Electric Pool Cleaner"

The Invention Explained

  • Problem Addressed: The patent identifies the cumbersome nature of conventional pool cleaners, which are often bulky and tethered to external power outlets or pump systems by long cords and hoses, making them difficult to maneuver for spot cleaning (ʼ460 Patent, col. 1:15-21).
  • The Patented Solution: The invention is a self-contained, hand-held, battery-powered pool cleaner. It features a "toroidal body" with an integrally molded handle, which houses the rechargeable batteries, motor, and impeller in a sealed compartment, eliminating the need for external connections during use. This design allows a user to easily carry and manipulate the cleaner underwater (ʼ460 Patent, Abstract; col. 2:50-56).
  • Technical Importance: This approach untethered pool cleaning from fixed power and suction sources, helping to create a new market category of highly portable cleaners for convenient spot-cleaning of pools and spas (Compl. ¶24-25).

Key Claims at a Glance

  • The complaint asserts at least independent claim 1 (Compl. ¶75, 76-78).
  • The essential elements of independent claim 1 include:
    • A hand-held submersible electrically-powered pool cleaner
    • A nozzle
    • A "toroidal body" with an integrally formed carrying handle
    • A rechargeable power source
    • An impeller and drive motor
    • A filter
    • A charging device
  • The complaint does not explicitly reserve the right to assert dependent claims.

U.S. Patent No. 7,060,182 - "Hand-Held Pool Cleaner"

The Invention Explained

  • Problem Addressed: Like its parent, this patent addresses the inconvenience of corded and hosed pool cleaners and the need for a portable, battery-powered alternative. It also notes the risk of electrical shorts in submersible devices with external charging ports (ʼ182 Patent, col. 1:28-42).
  • The Patented Solution: As a continuation-in-part, the '182 patent further develops the hand-held cleaner concept. A key improvement described is the use of a tapered filter housing to create a "cyclonic flow" of water. This is intended to cause debris to compact against the inner walls of the filter, maximizing debris retention and preventing the filter's suction path from becoming clogged prematurely ('182 Patent, col. 10:50-68).
  • Technical Importance: The cyclonic flow mechanism enhances the operational efficiency and effective debris capacity of the compact device, allowing for longer cleaning cycles before the unit must be emptied (ʼ182 Patent, col. 10:50-68).

Key Claims at a Glance

  • The complaint asserts at least independent claim 1 (Compl. ¶86, 87-89).
  • The essential elements of independent claim 1, which are structurally similar to claim 1 of the '460 patent, include:
    • A hand-held submersible electrically-powered pool cleaner
    • A nozzle
    • A "toroidal body" with an integrally formed carrying handle
    • Impeller means and a drive motor
    • A filter
  • The complaint does not explicitly reserve the right to assert dependent claims.

U.S. Patent No. 7,636,975 - "Pool Vacuum"

  • Technology Synopsis: This patent discloses a pool vacuum with several refinements aimed at improving usability. These include a poppet valve within the filter cone to allow for quick drainage of clean water when the device is lifted from the pool, an isolated charging circuit to prevent battery drainage in electrolytic water, and an exhaust gap design that can produce a net downward thrust to assist with control during operation ('975 Patent, Abstract).
  • Asserted Claims: At least independent claim 1 (Compl. ¶97).
  • Accused Features: The complaint accuses the Kokido Telsa 50 and Vektro V300 products of infringing this patent (Compl. ¶97).

U.S. Patent No. 8,281,441 - "Hand-Held Submersible Pool and Spa Power Cleaner"

  • Technology Synopsis: This patent describes a modular design where a removable drive assembly—containing the motor, impeller, and batteries—is inserted into a separate housing that holds the filter. This architecture facilitates easier servicing and component replacement. The invention also discloses dual outlet conduits to balance the discharge of filtered water ('441 Patent, Abstract).
  • Asserted Claims: The complaint asserts at least dependent claims 4, 5, 8, and 16, which depend from independent claim 1 (Compl. ¶105-107).
  • Accused Features: The complaint accuses the Kokido Telsa 50, Vektro V300, Wanda, and Lektra products of infringing this patent (Compl. ¶103).

U.S. Design Patent No. D556,396 - "Pool Vacuum"

  • Technology Synopsis: This patent claims the unique ornamental design for a pool vacuum. The claimed design consists of the visual appearance of the device, characterized by its overall configuration and the shape of its components, including a main body with an integrated, curved handle and a tapered, transparent nose cone ('D396 Patent, Figs. 1-8).
  • Asserted Claims: The single claim of the design patent for the ornamental design shown in the drawings.
  • Accused Features: The complaint alleges that the overall visual appearance of the Kokido Telsa 50 and Vektro V300 products is substantially similar to the patented design (Compl. ¶113, 115).

III. The Accused Instrumentality

Product Identification

The accused instrumentalities are various models of hand-held, battery-powered submersible pool vacuums manufactured by Kokido. These include the Telsa line (Telsa 10, 30, 50, 80), the Vektro line (T150, V300, X400), the Wanda, and the Lektra Vac (Compl. ¶16, 52).

Functionality and Market Context

The complaint describes the Accused Products as "Rechargeable Handheld Pool Vacuum" and "Battery Operated Vacuum" devices designed for cleaning pools and spas (Compl. ¶53-54). Images provided in the complaint depict self-contained, cordless units with a main body, an integrated handle, a vacuum head, and a debris collection chamber (Compl. Images 7-15). For example, Image 9 shows the Kokido Telsa 50, which is described as a "Rechargeable Electric Handheld Pool Vacuum" (Compl. ¶55). The complaint alleges these products are direct competitors to Plaintiff's products and are gaining market share, in part by being sold through the same retail channels (Compl. ¶25, 71).

IV. Analysis of Infringement Allegations

The complaint references claim chart exhibits for its infringement allegations (e.g., Exhibits 6-17) but does not include them with the filing. Therefore, the analysis is based on the narrative infringement theory presented in the body of the complaint.

'460 Patent Infringement Allegations

The complaint alleges that various accused products, including the Telsa and Vektro lines, directly infringe at least independent claim 1 of the '460 patent (Compl. ¶75-78). The narrative infringement theory appears to rely on the general characterization of the accused products as "hand-held rechargeable battery powered pool vacuums" (Compl. ¶7). The complaint's descriptions and the accompanying product images (Compl. ¶53-61, Images 7-15) suggest that Plaintiff's theory maps the core features of the accused devices—such as their self-contained power source, suction nozzle, internal filter, and integrated handle—to the corresponding elements of claim 1.

'182 Patent Infringement Allegations

The infringement theory for the '182 patent largely mirrors the theory for the '460 patent, as independent claim 1 of the '182 patent shares a similar structure. The complaint alleges the same set of accused products infringe claim 1 by embodying the features of a hand-held, submersible pool cleaner with an integrated handle and internal filter (Compl. ¶84, 86-89). The complaint does not provide specific factual allegations detailing how the accused products perform the more nuanced technical aspects described in the '182 patent, such as creating a "cyclonic flow."

Identified Points of Contention

  • Scope Questions: A primary point of contention for the '460 and '182 patents will likely be the construction of the term "toroidal body." The infringement allegation rests on the premise that the accused products' elongated bodies, which feature an opening created by an integrated handle, fall within this definition. The defense may argue for a narrower definition limited to a more classically "donut-shaped" geometry.
  • Technical Questions: For the later patents ('182, '975, '441), which claim more specific internal mechanisms (e.g., cyclonic flow, poppet drain valve, removable drive assembly), the complaint does not provide technical evidence showing that the accused products actually contain these features or operate in the claimed manner. A key question for the court will be whether discovery reveals a technical correspondence or a fundamental mismatch in the internal operation of the accused devices.
  • Visual Evidence Questions: The complaint presents a side-by-side visual comparison to support its design patent claim, annotating alleged similarities between the patented design and the accused product (Compl. ¶116, Images 16-17). This directly raises the factual question for the finder of fact: whether an ordinary observer would find the two designs substantially the same.

V. Key Claim Terms for Construction

  • The Term: "toroidal body" (appearing in claim 1 of the '460 patent and claim 1 of the '182 patent).
  • Context and Importance: This term appears in the independent claims of the two lead utility patents and is central to the infringement analysis. The viability of the infringement claim for these patents hinges on whether the physical form of the accused products can be considered a "toroidal body." Practitioners may focus on this term because its definition will likely determine whether a large category of the accused products read on the core claims.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The claims themselves provide context, defining the "toroidal body" as "having: a carrying handle for carrying, manipulating, and directing the cleaner during use, with the carrying handle being integrally formed from an upper portion of the toroidal body and an opening through the toroidal body" ('460 Patent, cl. 1; '182 Patent, cl. 1). A plaintiff may argue that this language serves as a definition, meaning any single-piece body that includes an integrated handle creating a pass-through opening is "toroidal" for the purposes of the patent, regardless of its overall shape.
    • Evidence for a Narrower Interpretation: The common technical and dictionary definition of a "toroid" is a surface generated by revolving a plane curve about an axis in its plane that does not intersect the curve (i.e., a donut shape). A defendant may argue that the term should be given this plain and ordinary meaning, which would exclude the elongated, non-uniform shape of the embodiments shown in the patent's own figures (e.g., '460 Patent, Fig. 2) and the accused products.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges that Defendants induced infringement by non-party end-users for all asserted patents (e.g., Compl. ¶74, 85). This allegation is based on Defendants selling the accused products with the knowledge and intent that customers would use them in an infringing manner, likely supported by evidence such as user manuals and marketing materials.
  • Willful Infringement: The complaint alleges willful infringement for all asserted patents, seeking enhanced damages (e.g., Compl. ¶79, 90). The allegations are based on two claims of pre-suit knowledge: 1) a direct notice letter sent from Plaintiff's counsel to Kokido on August 12, 2015 (Compl. ¶62), and 2) Kokido's prior business relationship purchasing a product from Plaintiff that was allegedly marked with the patent numbers (Compl. ¶63). The complaint includes a photograph, Image 2, purporting to show the patent markings on this prior product (Compl. p. 3).

VII. Analyst’s Conclusion: Key Questions for the Case

  • A core issue will be one of definitional scope: can the claim term "toroidal body," which has a specific geometric meaning, be construed broadly enough to read on the accused products' elongated, streamlined form factor, based on the patent's description of a body with an "opening" formed by an integral handle?
  • A key evidentiary question will be one of technical correspondence: for the more advanced features claimed in the later patents (e.g., the '975 patent's poppet valve or the '182 patent's cyclonic flow), does the internal operation of the accused products, once revealed in discovery, show the presence of the specific structures and functions required by the claims, or is there a fundamental mismatch?
  • A central question for the design patent claim will be one of visual comparison: would an ordinary observer, familiar with the prior art of pool cleaners, be deceived into purchasing an accused Kokido Telsa 50 believing it to be the product shown in the 'D396 design patent, considering the overall visual impression of both designs?