Yi Wu Shi Hong Zhi Dian Zi Ke Ji You Xian Gong Si v. TOMY Intl Inc

I. Executive Summary and Procedural Information

• Case Name: yi wu shi hong zhi dian zi ke ji you xian gong si d/b/a Bunwag-US v. Tomy International, Inc.
• Parties & Counsel:
  • Plaintiff: yi wu shi hong zhi dian zi ke ji you xian gong si d/b/a Bunwag-US (China)
  • Defendant: Tomy International, Inc. (Delaware)
  • Plaintiff's Counsel: AU LLC
• Case Identification: 1:26-cv-05104, N.D. Ill., 05/01/2026
• Venue Allegations: Venue is based on Defendant being a resident of the judicial district.
• Core Dispute: Plaintiff seeks a declaratory judgment that its baby bathtub products do not infringe Defendant's patent and/or that the patent is invalid, following an infringement accusation made by the Defendant through an e-commerce platform's patent dispute program.
• Technical Context: The technology relates to collapsible baby bathtubs designed to be portable, storable, and provide an elevated, stand-alone bathing station for infants.
• Key Procedural History: The complaint states this declaratory judgment action was precipitated by an infringement complaint filed by the Defendant in April 2026 against the Plaintiff's products via the Amazon Patent Evaluation Express (APEX) program.

Case Timeline

Date	Event
2008-11-20	'176' Patent Priority Date
2017-01-17	'176 Patent Issue Date
2026-04-DD	Defendant issues infringement complaint via Amazon APEX
2026-05-01	Complaint for Declaratory Judgment Filed

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

U.S. Patent No. 9,545,176 - "BATHTUB"

The Invention Explained

• Problem Addressed: The background of the '176 Patent discusses various types of bathtubs for children, implying a market need for a product that is both portable and storable like a collapsible or inflatable tub, but also provides the stable, stand-alone functionality of more rigid systems '176 Patent, col. 1:15-28
• The Patented Solution: The invention is a bathtub that combines a collapsible container with a set of collapsible legs '176 Patent, col. 2:45-54 The legs deploy to support the tub at an elevated position, while the container itself can be collapsed for compact storage or expanded to form an open, water-impervious basin '176 Patent, abstract The design specifies that in the fully collapsed state, the bathtub has an overall thickness that is substantially equal to the thickness of its rigid frame, making it flat and easy to store '176 Patent, col. 2:35-49
• Technical Importance: This approach seeks to provide a single product that offers the ergonomic benefits of an elevated bathing station for caregivers while also being highly portable and space-efficient for storage, addressing common constraints for parents in modern households.

Key Claims at a Glance

• The complaint identifies at least independent Claim 1 as being asserted by the Defendant Compl. ¶14 Compl. ¶21
• Independent Claim 1 of the '176 Patent recites:
  • a frame;
  • a container extending from the frame, the container including a water impervious, rigid bottom surface and a centerline extending substantially perpendicular to the bottom surface;
  • a plurality of leg assemblies coupled to the frame, movable between a collapsed and deployed position to support the container at an elevated location;
  • the container movable between a second collapsed position, and a second deployed position to form an open tub to receive a child to be bathed.
• The complaint does not explicitly reserve the right to assert dependent claims, as it is a declaratory judgment action filed by the accused infringer.

III. The Accused Instrumentality

Product Identification

The accused products are baby bathtubs sold on the Amazon.com storefront "Bunwag-US" under Amazon Standard Identification Numbers (ASINs) B0CTJXJL4T and B0CTJZG2HN (the "Products") Compl. ¶8

Functionality and Market Context

• The complaint provides a photograph of the Products, which appear to be infant bathtubs featuring a basin, a set of folding legs, and a digital display module Compl. ¶8 The photograph shows the Products in a deployed state, with the legs extended to elevate the basin Compl. ¶8 The basin itself appears to be constructed from a combination of rigid and flexible materials, suggesting it may be collapsible for storage.
• The Products are sold as consumer goods on the Amazon.com e-commerce platform Compl. ¶8

IV. Analysis of Infringement Allegations

The complaint is for declaratory judgment of non-infringement and does not contain a claim chart from the Plaintiff. The infringement theory is the Defendant's, which the Plaintiff alleges was asserted via the Amazon APEX program Compl. ¶12 Compl. ¶14 The following table outlines how the Defendant's infringement allegations may map the elements of Claim 1 onto the features of the accused Products, based on the visual evidence provided in the complaint.

'176 Patent Infringement Allegations

Claim Element (from Independent Claim 1)	Alleged Infringing Functionality	Complaint Citation	Patent Citation
a frame;	The upper rim of the accused Products' basin, to which the legs and collapsible tub walls are attached.	¶8	col. 2:65-67
a container extending from the frame, the container including a water impervious, rigid bottom surface...	The basin of the accused Products, which is designed to hold water and appears to have a distinct, solid bottom section.	¶8	col. 8:16-18
a plurality of leg assemblies coupled to the frame...movable between a...collapsed position...and a...deployed position...	The folding legs of the accused Products, shown in their deployed position in the complaint's photograph, which are attached to the basin's rim.	¶8	col. 8:20-25
the container movable between a second collapsed position, and a second deployed position to form an open tub...	The basin of the accused Products, which appears to have flexible walls that allow it to be collapsed for storage and expanded for use.	¶8	col. 8:29-32

Identified Points of Contention

• Scope Question: A potential dispute may arise over the term "rigid bottom surface." The infringement analysis may turn on whether the bottom of the accused Products' basin possesses the degree of rigidity contemplated by the patent, especially when compared to the flexible nature of the collapsible sidewalls.
• Technical Question: A key factual question for the court may be how the accused Products' container achieves its collapsibility. Evidence will be needed to determine if its mechanism of folding or collapsing aligns with the structure described and claimed in the '176 Patent, which involves a container with a "rigid bottom" that is nevertheless "movable between a second collapsed position, and a second deployed position."

V. Key Claim Terms for Construction

• The Term: "rigid bottom surface"
• Context and Importance: The construction of this term appears central to the infringement analysis. If the accused Products' bottom surface is deemed not "rigid" within the meaning of the claim, it could support a finding of non-infringement. Practitioners may focus on this term because the visual evidence suggests the entire basin may be made of a semi-flexible material, raising a question of degree.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: A party arguing for a broader definition might contend that "rigid" is a relative term, meaning simply that the bottom is rigid enough to be self-supporting and hold the weight of water and a child, as distinct from a non-rigid, fabric-like sling '176 Patent, col. 3:25-27
  • Evidence for a Narrower Interpretation: A party arguing for a narrower definition could point to the specification's description of the bottom as "substantially rigid, and substantially bowl-shaped" '176 Patent, col. 3:25-26 and formed of materials like "plastic" '176 Patent, col. 3:28-30, in contrast to the "pliant, flexible, resilient material" of the sidewall '176 Patent, col. 3:30-34 This distinction suggests the inventor contemplated two structurally different components, which could be used to argue for a stricter definition of "rigid."

VI. Other Allegations

The complaint is a declaratory judgment action for non-infringement and invalidity; it does not contain allegations of indirect or willful infringement.

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

The resolution of this declaratory judgment action will likely depend on the court's findings on two primary issues:

1. A question of definitional scope: Can the claim term "rigid bottom surface" be construed to read on the material and construction of the accused Products' basin bottom? The outcome will depend on whether "rigid" implies a specific material and structural standard or is a relative term defined by its function.

2. A question of invalidity: The Plaintiff has alleged that prior art invalidates the '176 Patent Compl. ¶19 A central issue will be whether Plaintiff can produce evidence of pre-existing products or publications that disclose all elements of the asserted claims, particularly the combination of a collapsible, elevated frame with a collapsible container featuring a rigid bottom.