Lee v. Zhongshan Xikunlun Trading Co

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Dae Hee Lee (Republic of Korea)
  • Defendant: Zhongshan XiKunLun Trading Company (People's Republic of China), and The Partnerships and Unincorporated Associations Identified on Schedule "A"
  • Plaintiff’s Counsel: JP&T LAW GROUP, Group
• Case Identification: 1:26-cv-00006, N.D. Ill., 01/02/2026
• Venue Allegations: Venue is based on allegations that Defendants conduct business in the district by operating interactive e-commerce storefronts, targeting Illinois residents for sales, and delivering accused products into the district.
• Core Dispute: Plaintiff alleges that Defendants’ cat litter mat products infringe a U.S. design patent covering the ornamental appearance of a litter mat.
• Technical Context: The dispute is in the field of pet accessories, specifically concerning the aesthetic design of mats intended to trap litter tracked by cats.
• Key Procedural History: The complaint does not mention any prior litigation, inter partes review proceedings, or licensing history related to the patent-in-suit.

Case Timeline

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

U.S. Design Patent No. D745,749 - "Litter Mat for Cat"

• Patent Identification: U.S. Design Patent No. D745,749, issued on December 15, 2015.

The Invention Explained

• Problem Addressed: Design patents do not contain a "background" section detailing a technical problem; their purpose is to protect the novel, ornamental appearance of an article of manufacture ('749 Patent, Title).
• The Patented Solution: The patent claims the specific ornamental design for a cat litter mat as depicted in its figures ('749 Patent, CLAIM). The design consists of the visual characteristics of a generally rectangular mat featuring a raised peripheral border and a top surface covered with a repeating pattern of raised, irregularly shaped, pebble-like elements ('749 Patent, FIG. 1, FIG. 2, FIG. 6). The patent explicitly disclaims certain features shown in broken lines as environmental and not part of the claimed design ('749 Patent, DESCRIPTION).
• Technical Importance: The complaint does not provide sufficient detail for analysis of the design's market significance.

Key Claims at a Glance

• Design patents contain a single claim. The asserted claim is for: "The ornamental design for a 'litter mat for cat,' as shown and described" ('749 Patent, CLAIM).
• The protected design is defined by the visual elements shown in the patent's drawings, the primary features of which are:
  • A generally rectangular overall configuration.
  • A continuous, raised border around the periphery of the mat.
  • A top surface populated with a dense, repeating pattern of raised, non-uniform oval or pebble-like shapes.
  • The specific visual impression created by the combination, arrangement, and appearance of these elements.

III. The Accused Instrumentality

Product Identification

The accused instrumentalities are "Litter Mat for Cat" products manufactured, imported, advertised, offered for sale, and/or sold by the Defendants (Compl. ¶1, ¶17). The Primary Defendant is alleged to operate online storefronts under the brand name "Conlun" on platforms including Amazon.com (Compl. ¶4).

Functionality and Market Context

The complaint alleges that Defendants sell the accused products through online marketplaces to consumers in the United States, including Illinois (Compl. ¶4, ¶12). A specific sale and delivery of an infringing product to a consumer in Illinois is alleged to have occurred prior to the complaint's filing (Compl. ¶13). The complaint does not provide further technical details about the accused products' features or market position.

IV. Analysis of Infringement Allegations

The complaint does not contain a claim chart or side-by-side visual comparison of the patented design and the accused products. The infringement theory is based on the allegation that Defendants' products incorporate the patented design. In design patent cases, infringement is determined by the "ordinary observer" test, which asks whether an ordinary observer, familiar with the prior art, would be deceived into believing the accused design is the same as the patented design.

The core of the infringement allegation is that the accused products are "substantially the same" as the design claimed in the '749 Patent, constituting a "reproduction, imitation, or colorable variation" of it (Compl., Prayer for Relief ¶1(i)). No probative visual evidence provided in complaint.

• Identified Points of Contention:
  • Overall Visual Appearance: The central factual dispute will be whether the overall visual impression of the accused products is substantially the same as the design shown in the '749 Patent. The analysis will focus on the similarity of the combination of the mat's rectangular shape, its raised border, and the specific size, shape, density, and arrangement of the pebble-like surface pattern.
  • Scope of Protection: A potential issue may be the scope of the design patent's protection. The question is whether the claimed design is limited to the exact pattern shown or if it can cover variations that create the same overall visual effect.

V. Key Claim Terms for Construction

The complaint does not provide sufficient detail for analysis of claim construction. In design patent litigation, the claim is defined by the drawings rather than words. The single claim of the '749 Patent recites "The ornamental design for a 'litter mat for cat,' as shown and described" ('749 Patent, CLAIM). Courts generally hold that detailed verbal construction is unnecessary for design patent claims, as the figures themselves provide the definition.

VI. Other Allegations

• Indirect Infringement: The complaint does not plead a separate count for indirect infringement. However, the prayer for relief seeks to enjoin Defendants from "aiding, abetting, or enabling others to infringe the Asserted Patent" (Compl., Prayer for Relief ¶1(ii)). The complaint lacks specific factual allegations to support knowledge or intent for an indirect infringement theory.
• Willful Infringement: Plaintiff alleges that, upon information and belief, Defendants had "actual or constructive notice of the Asserted Patent" and continued their infringing conduct, supporting a finding of willful infringement (Compl. ¶24). The complaint does not specify the basis for this alleged notice.

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

1. Visual Comparison: The case will likely be decided on the factual question of visual similarity. The central issue for the court will be whether an ordinary observer, comparing the accused cat litter mats to the figures in the '749 Patent, would find the two designs to be substantially the same.
2. Defendant Identification and Liability: A significant procedural hurdle may involve managing a case against a primary defendant and numerous other online sellers identified only in a schedule (Compl. ¶¶3, 5). Establishing the specific infringing acts of each distinct entity among the "Schedule A Defendants" will be a key evidentiary requirement for the Plaintiff.
3. Basis for Willfulness: A critical question for damages will be whether Plaintiff can produce evidence that Defendants had pre-suit knowledge of the '749 Patent. Without such evidence, the claim for willful infringement and potential for enhanced damages may be difficult to sustain (Compl. ¶24).