1:25-cv-08491
Kao v. Hengda Kite
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Juncheng Kao (China)
- Defendant: Weifang Hengda Kite Manufacturing Co., Ltd. (d.b.a. Hengda Kite) (China)
- Plaintiff’s Counsel: Aptum Law
- Case Identification: 1:25-cv-08491, N.D. Ill., 01/15/2026
- Venue Allegations: Venue is alleged to be proper because Defendant is not a resident of the United States and therefore may be sued in any judicial district.
- Core Dispute: Plaintiff alleges that Defendant’s kite products infringe a U.S. design patent covering the ornamental appearance of a kite.
- Technical Context: The dispute centers on the ornamental design features of kites, a consumer product category where visual appearance and differentiation are key market drivers.
- Key Procedural History: The complaint includes preemptive arguments challenging the validity of potential prior art. It contends that certain Chinese design patents were not publicly accessible to a person of ordinary skill in the art (POSITA) prior to the patent's priority date and that Amazon product pages are an unreliable source of prior art due to their dynamic and modifiable nature.
Case Timeline
| Date | Event |
|---|---|
| 2021-06-17 | D'279 Patent Priority Date (Application Filing) |
| 2022-10-18 | D'279 Patent Issue Date |
| 2026-01-15 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. D967,279 S - *“Kite”*
The Invention Explained
- Problem Addressed: Design patents protect the novel ornamental appearance of an article of manufacture rather than a functional solution to a technical problem. The ’279 Patent secures rights to a specific visual design for a kite (D’279 Patent, CLAIM).
- The Patented Solution: The patent claims the ornamental design for a kite as depicted in its 18 figures (D’279 Patent, DESCRIPTION). The design features a delta-shaped kite body with curved lower wing edges that flow into an elongated central spine, which extends significantly below the main body to form a tail-like structure (D’279 Patent, FIG. 1). The rear view illustrates the specific arrangement of structural spars and connectors that contribute to the overall visual impression (D’279 Patent, FIG. 2).
- Technical Importance: The patented design provides a distinct aesthetic for a consumer product, which may serve as a basis for market differentiation.
Key Claims at a Glance
- The patent contains a single claim for "The ornamental design for a kite, as shown and described" (D’279 Patent, CLAIM). The scope of this claim is defined by the solid lines in the patent's drawings.
- The ornamental design is characterized by the visual combination of features including:
- The overall delta-wing configuration.
- The curved profile of the lower wing edges.
- The elongated central spine that forms an integral, extended tail structure.
- The specific layout of structural elements visible from the rear view.
III. The Accused Instrumentality
Product Identification
The complaint identifies the "Kengda Kite," sold by Defendant Weifang Hengda Kite Manufacturing Co., Ltd. on Amazon under the Amazon Standard Identification Number (ASIN) B0DGKZNGHD (Compl. ¶¶ 24-25, p. 9).
Functionality and Market Context
The accused product is a kite sold to consumers in the United States through Amazon.com (Compl. ¶7). The complaint alleges that the Accused Products are "materially identical" to the design protected by the ’279 Patent (Compl. ¶26). To support this, the complaint provides a side-by-side visual comparison showing line drawings from the ’279 Patent next to photographs of the accused "Hengda Kite" (Compl. p. 2). This visual evidence juxtaposes the patented design with the accused product's front and rear appearance (Compl. p. 2).
IV. Analysis of Infringement Allegations
The central test for design patent infringement is the "ordinary observer" test, which asks whether an ordinary observer, familiar with the prior art, would be deceived into purchasing the accused product believing it to be the patented design. The complaint alleges that the Accused Products are "materially identical" to the patented design (Compl. ¶26). The primary evidence offered in the complaint is a direct, side-by-side comparison of the patent drawings and photos of the accused kite (Compl. p. 2). This comparison highlights the alleged similarities in the overall shape, proportions, and configuration of the kite's body and its integrated central spine/tail structure.
- Identified Points of Contention:
- Visual Similarity: The core of the dispute will be the application of the ordinary observer test. A fact-finder will need to compare the overall visual impression of the accused Hengda Kite with the design claimed in the ’279 Patent. The analysis will focus on whether the designs are substantially the same, such that a consumer might confuse one for the other.
- Prior Art Validity: A significant point of contention, introduced by the Plaintiff, concerns the validity of the patent over certain potential prior art references (Compl. ¶¶ 10-22). The Plaintiff argues that specific Chinese design patents should not qualify as prior art because they were not "publicly accessible" through reasonably diligent search methods available to a POSITA before the patent's priority date (Compl. ¶¶ 10-11). Further, the complaint challenges the reliability of Amazon product pages as prior art, alleging they can be altered or repurposed over time, making them untrustworthy evidence of what was publicly available on a specific date (Compl. ¶¶ 20-21).
V. Key Claim Terms for Construction
Claim construction in design patent litigation focuses on the visual impression of the design as a whole, as depicted in the patent figures, rather than the interpretation of specific textual terms. The scope of the claim is defined by what is shown in the solid lines of the drawings (D’279 Patent, DESCRIPTION). Accordingly, extensive disputes over the meaning of specific words are less common than in utility patent cases. The primary "construction" issue will be the holistic visual interpretation of the claimed design for comparison against the accused product and the prior art.
VI. Other Allegations
- Indirect Infringement: The complaint alleges that the Defendant induced infringement by "instructing and otherwise encouraging customers of the Accused Products to make and use the Accused Products" (Compl. ¶18).
- Willful Infringement: Plaintiff alleges that Defendant’s infringement was willful, asserting that Defendant knew of the ’279 Patent or, at a minimum, knew of the popular kite designs on the market, including the patented design, and continued its infringing activities (Compl. ¶26).
VII. Analyst’s Conclusion: Key Questions for the Case
- A central infringement question will be one of visual identity: From the perspective of an ordinary observer, is the overall ornamental appearance of the accused "Hengda Kite," including its shape and configuration, substantially the same as the design claimed in the ’279 Patent's drawings?
- A critical validity question, preemptively raised by the plaintiff, will concern the accessibility and reliability of prior art: Can Chinese design patents alleged to be undiscoverable through reasonably diligent searching, or dynamic Amazon product pages alleged to be unreliable, serve as legally cognizable prior art to invalidate the ’279 Patent?