Shenzhen Jisu Technology Wins Default Judgment in Neck Fan Patent Case

Case Overview

The Parties

The Patents at Issue

Four U.S. utility patents were asserted, all covering neck fan technology:

• U.S. Patent No. 11,635,083 B2 (App. No. 17/717,131)
• U.S. Patent No. 11,661,947 B2 (App. No. 17/471,178)
• U.S. Patent No. 11,719,250 B2 (App. No. 17/585,594)
• U.S. Patent No. 11,920,602 B2 (App. No. 18/134,571)

These patents collectively protect mechanical and structural innovations in wearable neck-mounted fan devices — a product category that has surged in commercial popularity globally. Claim charts submitted as exhibits specifically outlined how accused products infringed at least Claim 1 of the ‘083 Patent.

The Accused Products

The infringing products were neck fans sold through unauthorized e-commerce storefronts. Plaintiff submitted screenshot evidence demonstrating each storefront’s readiness to ship to Illinois consumers, establishing both jurisdiction and the commercial scale of the infringement.

Legal Representation

Plaintiff was represented by Bishop Diehl & Lee, Ltd., with attorneys Edward L. Bishop, Benjamin Adam Campbell, Nicholas S. Lee, and Sameeul Haque leading the action. No defense counsel appeared.

Litigation Timeline & Procedural History

Filed on August 23, 2024, in the Northern District of Illinois — a favored venue for Schedule A e-commerce IP actions due to its established precedents and efficient handling of multi-defendant cases — the case moved with notable speed. The choice of Illinois was strategically grounded: Plaintiff demonstrated that defendants actively targeted Illinois consumers through U.S.-shipping-enabled storefronts, satisfying personal jurisdiction requirements.

Chief Judge Jeremy C. Daniel presided. The court entered a preliminary injunction early in proceedings, freezing defendant assets held by third-party payment processors and marketplaces. Service was effectuated via email, a method the court deemed constitutionally adequate given the anonymous, online nature of the defendants. With no defendant responding within the answer period, default was entered and subsequently converted to final judgment — completing the full litigation cycle in under six months.

The Verdict & Legal Analysis

Outcome

The court granted Plaintiff’s Motion for Entry of Default and Default Judgment in full. The financial award structure per defaulting defendant was as follows:

A permanent injunction was issued against all defaulting defendants and their agents. Third-party providers — including Amazon, eBay, Temu, Walmart, PayPal, and Payoneer — were ordered to freeze and transfer funds within seven to fourteen calendar days.

Verdict Cause Analysis

The court found defendants liable on four counts of patent infringement (Counts I–IV), plus unfair competition (Count V) and unjust enrichment and unfair competition under Illinois common law (Counts VI–VII). Because no defendant contested the allegations, the complaint’s factual allegations were deemed admitted.

Critically, the court found infringement willful, triggering treble damages under 35 U.S.C. § 284. The willfulness finding, combined with the court’s designation of the case as exceptional under 35 U.S.C. § 285, enabled the attorney’s fees award — a meaningful deterrent signal beyond the base damages.

The jurisdictional analysis is worth noting: the court applied a “targeting” standard, finding personal jurisdiction satisfied where defendants operated commercial, interactive storefronts shipping to Illinois residents. This confirms that anonymous offshore sellers using major U.S. marketplace platforms cannot easily avoid U.S. court jurisdiction.

Legal Significance

This case reinforces several important doctrinal points for neck fan patent litigation and Schedule A practice broadly:

1. Email service is constitutionally sufficient for anonymous e-commerce defendants when combined with marketplace and payment processor notifications — a holding consistent with prevailing Northern District of Illinois practice.
2. Willfulness can be established by default when defendants fail to appear, enabling treble damages without the evidentiary burden typically required in contested cases.
3. Exceptional case status is achievable in default contexts, meaning attorney’s fees under § 285 are a realistic recovery component in e-commerce IP enforcement campaigns.

Strategic Takeaways

For Patent Holders: Shenzhen Jisu’s success reflects a well-executed patent assertion strategy — building a portfolio of related utility patents, filing in a favorable venue, moving quickly for a TRO and asset freeze, and using claim charts to document infringement at the outset. Portfolio breadth across four related patents strengthens enforcement leverage significantly.

For Accused Infringers: Failing to appear is rarely strategically sound. Default removes all defenses — including invalidity and non-infringement — and converts allegations into admitted facts. Companies selling products in competitive consumer electronics categories should maintain FTO (freedom to operate) clearance and engage counsel immediately upon receiving notice of litigation.

For R&D Teams: The neck fan market illustrates how rapidly a consumer product category can become heavily patent-encumbered. Engineering teams developing wearable cooling devices should conduct rigorous FTO analyses against portfolios held by market leaders before product launch.

Industry & Competitive Implications

The neck fan category has experienced explosive global growth, driven by climate awareness and remote outdoor activity trends. With multiple manufacturers — particularly from Chinese production ecosystems — competing on major U.S. e-commerce platforms, patent disputes in this space are intensifying.

Shenzhen Jisu’s four-patent portfolio and aggressive enforcement posture signals that IP-sophisticated Chinese manufacturers are now asserting, not merely defending, U.S. patent rights. This represents a meaningful shift in the competitive landscape: U.S.-registered IP is increasingly being used by Chinese innovators to secure market exclusivity on American platforms.

For brands and resellers operating in the personal cooling device sector, this verdict reinforces that marketplace anonymity offers no real protection. Amazon, eBay, Temu, and Walmart have demonstrated willingness to comply with court-ordered account suspensions and fund transfers, making the Schedule A model an effective enforcement tool.

Licensing negotiations in this category will likely intensify. Companies seeking to enter the neck fan market should budget for IP clearance and potential licensing costs as standard pre-launch due diligence.

FAQ

What patents were asserted in Shenzhen Jisu Technology v. Schedule A Defendants?

Four U.S. utility patents: Nos. 11,635,083; 11,661,947; 11,719,250; and 11,920,602 — all covering neck fan technology.

Why did Plaintiff win by default judgment?

No defendant appeared or answered. Under federal rules, uncontested allegations are deemed admitted, entitling the plaintiff to default judgment and enabling willful infringement and exceptional case findings.

How does this case affect neck fan patent litigation broadly?

It confirms that patent holders with registered utility portfolios can efficiently enforce rights against anonymous e-commerce sellers across major U.S. platforms, recovering trebled damages and attorney’s fees within approximately 160 days.