Aiming Tang v. Hangzhou Zhenshan Wangluo Keji Youxian Gongsi

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Aiming Tang (China)
  • Defendant: Hangzhou zhenshan wangluo keji youxian gongsi, d/b/a NexusDrive (China)
  • Plaintiff’s Counsel: Glacier Law LLP
• Case Identification: 1:25-cv-07187, N.D. Ill., 06/26/2025
• Venue Allegations: Venue is alleged based on Defendant operating interactive e-commerce stores that target consumers in the United States, including Illinois, offering shipping to the district, accepting payment in U.S. dollars, and causing substantial injury to the Plaintiff in Illinois.
• Core Dispute: Plaintiff alleges that Defendant’s towing device products, sold online under the brand NexusDrive, infringe a patent related to a vehicle towing hitch with a damping function.
• Technical Context: The technology pertains to mechanical vehicle hitches, specifically designs that incorporate an adjustable mechanism to reduce movement, noise, and shock during towing.
• Key Procedural History: The complaint notes that Plaintiff discovered the alleged infringement through an "anti-infringement program that includes investigating suspicious websites and online marketplace listings." No prior litigation, licensing, or IPR proceedings are mentioned.

Case Timeline

Date	Event
2022-03-08	'973 Patent Priority Date
2022-09-20	'973 Patent Issue Date
2025-06-26	Complaint Filing Date

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

• Patent Identification: U.S. Patent No. 11,446,973, "TOWING DEVICE WITH DAMPING FUNCTION", issued September 20, 2022.

The Invention Explained

• Problem Addressed: The patent describes a problem in prior art towing devices where a gap between a connecting pin and its corresponding hole causes the connection to sway, collide, and create noise during use, which can lead to abrasion and unsafe towing conditions (’973 Patent, col. 1:23-30).
• The Patented Solution: The invention proposes a mechanical damping system to solve this problem. A "cushion" is sleeved over the main bar of the hitch (the "towing cantilever"). A "tightening bolt" is then used to push this cushion firmly against the vehicle's fixed hitch receiver, filling any gaps. This action is intended to restrain axial movement, absorb shock, and create a steadier, quieter connection between the towing vehicle and the trailer (’973 Patent, col. 3:5-20; Abstract).
• Technical Importance: The described solution provides a method to actively eliminate mechanical "play" in a standard hitch connection, aiming to enhance safety and reduce wear on towing components (’973 Patent, col. 3:12-25).

Key Claims at a Glance

• The complaint asserts independent Claim 1 (’973 Patent, col. 8:1-11; Compl. ¶¶ 13, 26).
• The essential elements of Claim 1 are:
  • A towing device comprising a towing main body and a towing assembly.
  • The main body includes a "towing cantilever" and a "vertical adjustment arm."
  • The cantilever is fixed to a vehicle's pre-arranged "fixed seat" via "fixing pins."
  • A "cushion" is sleeved on the towing cantilever, located between the fixing holes and the vertical adjustment arm.
  • A "tightening bolt" is provided on one side of the cushion.
  • The tightening bolt can be rotated to "push the cushion" so that its end surface "is abutted against the fixed seat."
• The complaint notes the existence of nine dependent claims and reserves the right to assert them later (Compl. ¶13).

III. The Accused Instrumentality

Product Identification

• The accused instrumentalities are "Towing Device Products" sold by Defendant under the name "NexusDrive" on the e-commerce marketplace Amazon.com (Compl. ¶¶ 1, 7, 16).

Functionality and Market Context

• The complaint alleges these are towing devices that incorporate Plaintiff's patented invention, which features an "integrated damping function designed to reduce axial movement and enhance towing stability" (Compl. ¶14). The complaint asserts that the existence of these "Infringing Products" has hampered Plaintiff's ability to enter and expand its market share (Compl. ¶1). The complaint does not provide specific technical details about the operation of the accused products beyond the general allegation of infringement.

IV. Analysis of Infringement Allegations

The complaint alleges that Defendant’s "Infringing Products" infringe at least Claim 1 of the ’973 Patent (Compl. ¶26). It states that a claim chart demonstrating this infringement is provided as Exhibit 3, but this exhibit was not included with the filed complaint (Compl. ¶26). Therefore, a detailed element-by-element analysis based on the plaintiff's specific allegations is not possible. The infringement theory rests on the allegation that the accused towing devices sold by Defendant on Amazon.com embody the patented combination of a towing cantilever, an adjustable cushion, and a tightening bolt that provides a damping function as recited in Claim 1 (Compl. ¶¶ 1, 13, 16).

No probative visual evidence provided in complaint.

Identified Points of Contention

• Technical Questions: A primary question for the court will be factual: do the accused "NexusDrive" products actually contain a mechanism that functions as the claimed "cushion" and "tightening bolt"? The case will require evidence demonstrating that the accused products have a component that is "pushed" by a rotatable "bolt" to abut a "fixed seat" and thereby perform the specific damping function required by the claim language.
• Scope Questions: The dispute may turn on the interpretation of the claim term "fixed seat pre-arranged at a rear end of a towing vehicle." The infringement analysis will need to determine if the standard receiver hitch on a vehicle, into which the accused product is inserted, qualifies as the claimed "fixed seat" that the cushion is "abutted against."

V. Key Claim Terms for Construction

• The Term: "cushion (27)"

  • Context and Importance: This term is central to the invention's damping function. Its construction will determine the scope of protected anti-sway mechanisms. Practitioners may focus on this term because the functionality of the entire invention depends on how this element is defined and what structures it covers.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: Claim 1 describes the cushion functionally, as an element that is "sleeved on the towing cantilever" and "pushed" by a bolt, without specifying its material or internal structure (’973 Patent, col. 8:5-11). This may support a construction covering any block or component that performs this role.
    • Evidence for a Narrower Interpretation: The specification discloses that the cushion "includes several damping pieces (35)" and is depicted in figures as a distinct, multi-grooved block (e.g., ’973 Patent, FIG. 5; col. 5:30-31). This could support an argument that the term is limited to a structure with these specific characteristics.

• The Term: "tightening bolt (28)"

  • Context and Importance: This is the actuating component of the claimed invention. Its definition is critical because it dictates how the damping function is achieved.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The claim requires only that the bolt "can be rotated to push the cushion," suggesting any rotatable fastener performing this action could infringe (’973 Patent, col. 8:8-9).
    • Evidence for a Narrower Interpretation: A specific embodiment describes a more complex arrangement where the tightening screw passes through a "through hole (33)" on the vertical adjustment arm and engages a "threaded hole (32)" on a separate "adjustment plate (31)" (’973 Patent, col. 5:8-17). A defendant may argue that this disclosed structure limits the scope of the term.

VI. Other Allegations

Indirect Infringement

• The complaint makes a passing allegation of indirect infringement and requests relief for "aiding, abetting, [or] contributing to" infringement (Compl. ¶¶ 25, A.b.). However, it does not plead specific facts to support a claim for either induced or contributory infringement, such as allegations related to user manuals, marketing materials, or knowledge of specific infringing uses by customers.

Willful Infringement

• The complaint alleges that Defendant's infringement "has been and continues to be willful" (Compl. ¶30). The basis for this allegation appears to be that Defendant's conduct is knowing and intentional, aimed at taking "unfair advantage of the enormous time, effort, and expense spent in connection with the '973 Patent" (Compl. ¶38). The complaint does not allege pre-suit knowledge of the patent.

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

• A key evidentiary question will be one of factual correspondence: Does the accused NexusDrive towing device actually incorporate the specific mechanical assembly recited in Claim 1? As the complaint lacks any images or technical descriptions of the accused product, this question can only be resolved through discovery and will hinge on whether the product has a translatable "cushion" that is actively pushed by a "tightening bolt" to abut a fixed part of the vehicle's hitch.
• The case may also turn on a question of definitional scope: How will the term "cushion" be construed? The court will need to decide if the term covers any generic component used to fill a gap, or if its meaning is limited by the specification's disclosure of a distinct element comprising "several damping pieces," which could narrow the scope of infringement.
• A final core issue will be one of enforcement and damages: Given that both parties are identified as entities in China and the sales occur through a third-party online marketplace, a central practical challenge for the plaintiff, should it prevail, will be the effective enforcement of any injunction and the collection of a potential damages award.