DCT

2:25-cv-02734

Xiamen Huangyudu Cosmetics Co Ltd v. Interlink Products Intl Inc

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Key Events
Complaint

I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 2:25-cv-02734, W.D. Wash., 12/30/2025
  • Venue Allegations: Plaintiff alleges venue is proper in the Western District of Washington because Defendant purposefully directed patent enforcement activities into the district by initiating an Amazon "Patent Evaluation Express" (APEX) proceeding and transmitting enforcement communications to Amazon personnel located in Seattle.
  • Core Dispute: Plaintiff seeks a declaratory judgment that its rain shower head products do not infringe Defendant’s U.S. Patent No. 12,485,435, and/or that the patent is invalid.
  • Technical Context: The dispute centers on multi-function showerheads capable of directing water through different sets of nozzles to produce varied spray patterns, such as a standard shower spray or a high-pressure cleaning jet.
  • Key Procedural History: The action arises from Defendant’s accusation of infringement made through Amazon’s APEX program, a third-party neutral evaluation process. Defendant’s enforcement efforts threatened the removal of Plaintiff’s product listings from the Amazon marketplace, creating the basis for the declaratory judgment action.

Case Timeline

Date Event
2020-12-10 ’435 Patent Priority Date (from application Ser. No. 17/247,425)
2025-12-02 ’435 Patent Issued
2025-12-12 Amazon notifies Plaintiff of Defendant's infringement report
2025-12-30 Complaint for Declaratory Judgment Filed

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

U.S. Patent No. 12,485,435 - *"Showerhead Having Selector For Directing Water Flow In Independent Directions"*

  • Patent Identification: U.S. Patent No. 12,485,435, "Showerhead Having Selector For Directing Water Flow In Independent Directions," issued December 2, 2025 (’435 Patent).

The Invention Explained

  • Problem Addressed: The patent’s background section notes that conventional showerheads are designed primarily for showering, and their resulting water pressure and spray patterns may be "undesirable for cleaning purposes" such as rinsing shower walls or tubs (’435 Patent, col. 1:17-29).
  • The Patented Solution: The invention is a showerhead with a selector mechanism that allows a user to direct water flow through different, independent sets of nozzles (’435 Patent, Abstract). In addition to the standard nozzles on the showerhead's main face, the invention includes separate nozzles, often located on a different part of the head, which are configured to produce distinct spray types, such as a high-pressure "jet stream" or a wide "fan-shaped spray" specifically for cleaning tasks (’435 Patent, col. 4:12-20). A flow selector lever or switch allows the user to move between these modes (’435 Patent, col. 4:36-40).
  • Technical Importance: This design aims to combine the functions of a standard showerhead and a specialized cleaning tool into a single plumbing fixture, eliminating the need for separate cleaning implements (’435 Patent, col. 1:17-29).

Key Claims at a Glance

  • The complaint focuses on independent Claim 1, which was asserted in the underlying APEX proceeding (Compl. ¶23).
  • Essential elements of asserted independent Claim 1 include:
    • A showerhead comprising a head portion and a handle.
    • A plurality of first nozzles for directing water in a first direction.
    • At least one second nozzle in the head portion for directing water in a second direction.
    • At least one third nozzle adjacent to the second nozzle for directing water in a third direction, where the second and third directions are substantially the same and transverse to the first.
    • The second nozzle creates a first type of water flow, and the third nozzle creates a different, second type.
    • A flow selector moveable between a first position (directing water to the first nozzles), a second position (directing water to the second nozzle), and a third position (directing water to the third nozzle).
    • The flow selector is configured to remain in a selected position without continuous external force.
  • The complaint notes that dependent claims incorporate the limitations of claim 1 (Compl. ¶26).

III. The Accused Instrumentality

Product Identification

  • Plaintiff's "rain shower head" sold on Amazon.com under various ASINs (the "Accused Product") (Compl. ¶¶5, 23).

Functionality and Market Context

  • The complaint describes the Accused Product as employing a "materially different flow-selection structure" from that recited in the ’435 Patent (Compl. ¶23).
  • Specifically, the Accused Product allegedly uses a "rotatable disc/faceplate mechanism" to switch between modes, in contrast to the claimed "flow selector moveable between" discrete positions (Compl. ¶23).
  • The complaint alleges the Accused Product’s selector routes water to "side outlets and to selected subsets of faceplate nozzles," and includes an "off" position where no water is discharged, configurations which Plaintiff contends are not recited in Claim 1 (Compl. ¶23).
  • The Amazon marketplace is identified as Plaintiff's "primary sales channel in the United States," making the threatened removal of listings a significant commercial risk (Compl. ¶14).
  • No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

Claim Chart Summary

  • The complaint for declaratory judgment argues for non-infringement. The following table summarizes Plaintiff's primary non-infringement arguments as they map to the elements of Claim 1.

’435 Patent Non-Infringement Arguments (per Plaintiff)

Claim Element (from Independent Claim 1) Plaintiff's Non-Infringing Functionality Argument Complaint Citation Patent Citation
a flow selector moveable between a first position in which water flow is directed through the plurality of first nozzles, a second position..., and a third position... The Accused Product uses a "rotatable disc/faceplate mechanism" which is a "materially different flow-selection structure" from the recited flow selector. ¶23 col. 9:12-18
a first position in which water flow is directed through the plurality of first nozzles The Accused Product's selector positions route water to "side outlets and to selected subsets of faceplate nozzles," rather than through the entire "plurality of first nozzles" as allegedly required by the "first position." ¶23 col. 9:13-15
[Implicit: Claim 1 only recites three functional positions] The Accused Product includes an additional "off" position in which no water is discharged, which is a configuration not recited in Claim 1. ¶23 col. 9:12-18

Identified Points of Contention

  • Scope Questions: A primary issue will be whether the claim term "flow selector moveable between a first position..., a second position..., and a third position" can be construed to read on the Accused Product's "rotatable disc/faceplate mechanism." The dispute may focus on whether the claim requires a specific type of linear or toggling selector as depicted in the patent's embodiments or is broad enough to cover rotational selectors.
  • Technical Questions: The complaint raises a factual question regarding the operation of the Accused Product. Specifically, does its water-routing scheme, which allegedly directs water to "subsets of faceplate nozzles," differ materially from the claimed "first position" that directs flow "through the plurality of first nozzles"? This may hinge on whether "the plurality" requires all first nozzles to be active simultaneously. The presence of an "off" position also raises the question of whether this additional functionality places the product outside the literal scope of the claim.

V. Key Claim Terms for Construction

The Term: "a flow selector moveable between a first position..., a second position..., and a third position"

  • Context and Importance: This term is central to Plaintiff's non-infringement argument that its "rotatable disc" is structurally and operationally different from the claimed selector (Compl. ¶23). The construction of this term will determine whether different mechanical means for achieving flow selection fall within the claim's scope.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The claim language itself does not specify the mechanical nature of the "flow selector," only its function of moving between defined positions. Parties arguing for a broader scope may contend that "moveable" is a general term not limited to the specific switch-like embodiment shown.
    • Evidence for a Narrower Interpretation: The patent consistently depicts the "flow selector" (116) as a lever or switch that actuates a "flow director" (208) to align with one of three distinct plenums (212a, 212b, 212c) (’435 Patent, Figs. 2A-4B; col. 4:36-40). This consistent depiction of a specific mechanical arrangement could be used to argue that the claim scope is tied to this type of structure, rather than any mechanism that selects a flow path.

The Term: "wherein the flow selector is configured to remain in one of the first position, the second position, or the third position without an external force continuously maintaining a desired position"

  • Context and Importance: This "retention" or "detent" feature is a specific functional requirement of the selector. While not a direct point of argument in the complaint's narrative, proving infringement will require showing the Accused Product meets this limitation. Practitioners may focus on this term because mechanical retention mechanisms can vary widely, and any mismatch could be a basis for non-infringement.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The claim language is functional, describing the result (remaining in position) rather than the mechanism. This could support a reading that covers any method of retention, such as friction-based stops, common in rotational selectors.
    • Evidence for a Narrower Interpretation: The specification discloses a specific structure for achieving this function: "one or more spring loaded pins 254... to engage a corresponding one or more of a plurality of indentations 256" (’435 Patent, col. 5:13-16). A defendant might argue that this detailed disclosure limits the claim's meaning to a detent mechanism of this type.

VI. Other Allegations

  • Indirect Infringement: The complaint seeks a declaration of non-infringement for indirect infringement, alleging that Plaintiff has not encouraged or intended for customers to practice every claim limitation and that the Accused Product is "a staple article of commerce suitable for substantial non-infringing uses" (Compl. ¶25).

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

  • A core issue will be one of structural scope: Is the claim term "flow selector moveable between" three distinct positions limited to the switch-and-plenum architecture disclosed in the patent's embodiments, or is it broad enough to encompass the "rotatable disc/faceplate mechanism" used in the Accused Product?
  • A key factual and legal question will be one of operational correspondence: Does the Accused Product’s functionality—which allegedly includes an "off" position and routes water to "subsets of faceplate nozzles"—materially diverge from the specific operational states defined by the "first position," "second position," and "third position" in Claim 1, thereby avoiding literal infringement?
  • The case also presents a significant validity challenge: Will the combination of prior art references cited in the complaint, which allegedly disclose features like multi-function selectors, adjacent nozzles, and detent mechanisms, be sufficient to demonstrate that the specific configuration claimed in the ’435 Patent would have been obvious to a person of ordinary skill in the art?