DCT
2:25-cv-16605
Shenzhen Jisu Technology Co Ltd v. Shenzhen Fosala Technology Co Ltd
Key Events
Complaint
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Shenzhen Jisu Technology Co., Ltd. (China)
- Defendant: SHENZHEN FOSALA TECHNOLOGY CO., LTD., et al. (China)
- Plaintiff’s Counsel: John H. Choi & Associates LLC
- Case Identification: 2:25-cv-16605, D.N.J., 10/14/2025
- Venue Allegations: Plaintiff alleges venue is proper in the District of New Jersey because Defendants target U.S. consumers, including New Jersey residents, through interactive e-commerce stores, offer shipping to the state, and solicit local customer reviews.
- Core Dispute: Plaintiff alleges that Defendants’ M5, R5, S10, S9, and M15 series of personal neck fans infringe a utility patent and a design patent related to wearable fan technology.
- Technical Context: The dispute concerns the market for personal, wearable cooling devices, a consumer electronics category focused on providing hands-free cooling for users.
- Key Procedural History: The complaint details a prior business relationship, including a 2025 licensing agreement under which some Defendants were licensed to practice the ’602 Patent. Plaintiff alleges Defendants breached this agreement by failing to pay royalties, leading Plaintiff to terminate the license. This prior relationship and alleged knowledge of the patent forms the basis for the willfulness allegations.
Case Timeline
| Date | Event |
|---|---|
| 2019-10-25 | ’602 Patent Priority Date |
| 2020-09-07 | D’932 Patent Filing Date |
| 2021-08-24 | D’932 Patent Issue Date |
| 2022-01-27 | Jisu and FoSala enter into initial licensing agreement (patents-in-suit not included) |
| 2024-03-05 | ’602 Patent Issue Date |
| 2025-01-01 | New licensing agreements become effective, including the ’602 Patent |
| 2025-06-23 | Plaintiff notifies Defendants of license termination |
| 2025-10-14 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 11,920,602 - Neck Fan
The Invention Explained
- Problem Addressed: The patent’s background section identifies safety and comfort issues with existing neck fans, noting that exposed fan blades can entangle hair and that concentrated air outlets can create uncomfortable airflow (’602 Patent, col. 1:35-41).
- The Patented Solution: The invention proposes a bladeless design where multiple fan assemblies are housed within a U-shaped shell worn around the neck. This shell is comprised of an inner and outer wall that cooperatively define a "receiving space" which functions as an air duct (’602 Patent, col. 1:44-51). The claimed configuration involves the fan assemblies drawing air through inlets on the inner shell (facing the neck) and driving that air into the duct for expulsion through outlets, aiming for a safer and more distributed cooling effect (’602 Patent, col. 1:51-60).
- Technical Importance: This enclosed, multi-fan approach sought to improve user safety and comfort over prior art designs in the growing market for personal wearable fans (’602 Patent, col. 1:28-34).
Key Claims at a Glance
- The complaint asserts independent Claim 1 and reserves the right to assert others (Compl. ¶36).
- Claim 1 requires:
- An inner shell, disposed near the neck
- An outer shell, connected to the inner shell and cooperatively defining a receiving space
- A plurality of fan assemblies received in the receiving space
- The inner shell defines a plurality of air inlets, located near and facing towards the neck
- At least a part of the receiving space serves as an air duct communicating with the air inlets
- Each fan assembly is configured to intake air from an outside of the neck fan through the corresponding air inlets and drive the air to flow into the air duct
U.S. Design Patent No. D928,932 - Fan
The Invention Explained
- Problem Addressed: Design patents protect the novel, non-functional ornamental appearance of an article of manufacture. This patent does not describe a technical problem.
- The Patented Solution: The D’932 Patent claims the ornamental design for a fan. The design is characterized by the overall visual impression of a U-shaped, wearable device featuring a smooth, continuous form, bulbous ends with distinct circular elements, and a uniform series of air outlets situated along the top inner edge of the device (D’932 Patent, FIGS. 1-3).
- Technical Importance: The design provides a specific aesthetic for a personal neck fan, distinguishing it visually from other products in the market.
Key Claims at a Glance
- The single claim is for "The ornamental design for a fan, as shown and described" (D’932 Patent, Claim).
III. The Accused Instrumentality
Product Identification
- The M5, R5, S10, S9, and M15 neck fans (Compl. ¶17).
Functionality and Market Context
- The accused products are battery-powered, wearable fans designed to be worn around a user's neck to provide a hands-free cooling airflow (Compl. ¶9). The complaint alleges these products are manufactured by Defendant SMT and sold by the other Defendants through various online marketplaces, including Amazon and Walmart (Compl. ¶¶4, 14, 17). A photograph provided in the complaint depicts the accused M5 Neck Fan as a U-shaped wearable device (Compl. p. 7).
IV. Analysis of Infringement Allegations
The complaint references exemplary claim charts attached as exhibits; however, these exhibits were not included with the filed complaint (Compl. ¶¶35, 45). The analysis below is based on the narrative allegations and visual evidence within the complaint itself.
’602 Patent Infringement Allegations
The complaint alleges that the Accused Products meet every element of at least Claim 1 of the ’602 Patent (Compl. ¶35).
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| an inner shell, disposed near the neck | The accused products have a U-shaped body with an inner surface designed to be worn near the user's neck. | ¶35; p. 7 | col. 1:45-46 |
| an outer shell, connected to the inner shell ... [defining] a receiving space | The accused products have an outer surface that, with the inner surface, forms the body of the device and encloses internal components. | ¶35; p. 7 | col. 1:46-48 |
| a plurality of fan assemblies... received in the receiving space | The accused products contain internal fan components that generate airflow. | ¶35 | col. 1:49-51 |
| the inner shell defines a plurality of air inlets, located near and facing towards the neck | The complaint alleges this element is met, though visual evidence in the complaint does not clearly show the location of the air inlets. | ¶35 | col. 1:51-53 |
| at least a part of the receiving space serves as an air duct | The internal space within the accused products' housing channels the air from the fans to the outlets. | ¶35 | col. 1:53-55 |
| each of the plurality of fan assemblies is configured to intake air from an outside of the neck fan through the corresponding plurality of air inlets and to further drive the air to flow into the air duct | The fan assemblies in the accused products are alleged to draw in air and propel it through the device's internal ducting to the air outlets. | ¶35 | col. 1:57-60 |
- Identified Points of Contention:
- Scope Questions: The primary point of contention may be the claim limitation requiring "air inlets, located near and facing towards the neck." A photograph of the accused R5 product appears to show air inlets on the outer surface, away from the neck (Compl. p. 7). This raises the question of whether the accused products literally infringe this element, or if Plaintiff will need to rely on the doctrine of equivalents.
D’932 Patent Infringement Allegations
The complaint alleges that the accused M5 neck fans are "substantially similar to, or at least a colorable imitation of the claimed design" of the D’932 Patent (Compl. ¶45).
- Identified Points of Contention:
- Technical Questions: The infringement analysis will turn on the "ordinary observer" test. The central question is whether an ordinary observer, familiar with prior art designs, would be deceived into purchasing the accused M5 fan believing it to be the product embodying the patented design. The outcome will depend on a direct visual comparison of the accused M5 product (Compl. p. 7) and the figures of the D’932 Patent (D’932 Patent, FIGS. 1-8).
V. Key Claim Terms for Construction
For the ’602 Patent, the construction of the following term appears central to the dispute.
- The Term: "air inlets, located near and facing towards the neck"
- Context and Importance: The location of the air inlets is a specific, distinguishing feature of Claim 1. Whether the accused products meet this limitation will likely be a primary focus of litigation. Practitioners may focus on this term because a narrow construction could be dispositive of literal infringement, given that many commercial neck fans have external air intakes.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: A party might argue that "near... the neck" does not require direct contact or placement on the innermost surface, but rather refers to the general region from which air is drawn. The patent's overall purpose is to provide cooling, and one could argue that the precise path of intake air is less critical than the overall structure, suggesting a broader functional interpretation may be appropriate.
- Evidence for a Narrower Interpretation: The plain language of the claim is specific and unambiguous ("inner shell defines a plurality of air inlets... facing towards the neck") (’602 Patent, col. 15:20-22). The abstract reiterates this configuration (’602 Patent, Abstract). This specificity suggests the patentee deliberately chose this language to distinguish the invention from prior art, supporting a narrower construction limited to inlets on the inner surface.
VI. Other Allegations
- Indirect Infringement: The complaint alleges that Defendants actively induce infringement by encouraging consumers to use the accused products in the United States (Compl. ¶¶37, 47).
- Willful Infringement: The willfulness allegation for the ’602 Patent is based on Defendants' alleged actual knowledge of the patent through the 2025 Licensing Agreements, which explicitly identified it (Compl. ¶40). The allegation for the D’932 Patent is based on a more general assertion that Defendants were aware of the patent during the relevant time period (Compl. ¶50).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of claim scope: can the phrase "air inlets, located near and facing towards the neck" in Claim 1 of the ’602 Patent be construed to read on the accused products, which based on visual evidence may have air inlets on their outer surfaces?
- A central legal and factual question will be one of design similarity: would an ordinary observer, comparing the ornamental design claimed in the D’932 Patent with the accused M5 neck fan, be deceived into believing the products embody the same design?
- The parties' prior licensing history raises a key question of estoppel and willfulness: how does the 2025 licensing agreement for the ’602 Patent, and its subsequent alleged breach and termination, affect the claims for infringement, willfulness, and damages for the period after the alleged termination?