Design Patent Showdown: Electric Water Flosser Infringement Battle in Illinois
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📋 Case Summary
| Case Name | Guowei Zhang, et al. v. Schedule A Defendants |
| Case Number | 1:23-cv-06434 (N.D. Ill.) |
| Court | Illinois Northern District Court |
| Duration | Aug 2023 – Sep 2024 1 year 1 month |
| Outcome | Plaintiff Likely Win — Default Judgments/Settlements |
| Patents at Issue | |
| Accused Products | Electric Water Flossers |
Case Overview
The Parties
⚖️ Plaintiff
Chinese e-commerce entrepreneur and entity asserting design patent rights against marketplace infringers.
🛡️ Defendant
Dozens of online marketplace sellers, including Jahyshow Technology Co., Ltd., Socialme, and Fairnull, accused of infringement.
Patents at Issue
This landmark case involved a single design patent covering the ornamental design of an electric water flosser, highlighting the growing trend of enforcing design patents against marketplace infringers. Design patents protect ornamental appearance rather than functional technology.
- • US D966,499 S — Ornamental design of an electric water flosser
Designing a similar product?
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The Verdict & Legal Analysis
Outcome
The specific verdict and damages are not disclosed in available records, but the case structure is highly consistent with default judgments or settlements in favor of plaintiffs. The 379-day duration from filing to closure is typical for Schedule A design patent cases that resolve through default judgments, voluntary dismissals, or early settlements rather than proceeding to full trial.
Key Legal Issues
The core legal issue in design patent infringement is the “ordinary observer” standard established in Egyptian Goddess, Inc. v. Swisa, Inc. (Fed. Cir. 2008). This test determines if an ordinary observer, familiar with the prior art, would be deceived into believing the accused product is the same as the patented design. This case highlights the power of 35 U.S.C. § 289, which allows patent holders to recover total profits from infringing articles, making it a potent enforcement tool against marketplace infringers, particularly in the consumer product sector.
Freedom to Operate (FTO) Analysis: Electric Water Flosser Design
This case highlights critical IP risks in electric water flosser design. Choose your next step:
📋 Understand This Case’s Impact
Learn about the specific risks and implications from this litigation.
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High Risk Area
Electric water flosser designs
1 Design Patent, Many Similar Products
In electric water flosser space
Design-Around Options
Available for most claims
✅ Key Takeaways
Design patent damages can include total profits from products where design drives consumer demand.
Search related case law →The “ordinary observer” standard is central to infringement analysis, making visual comparison crucial.
Explore precedents →Schedule A complaints offer efficient enforcement against multiple marketplace infringers.
Learn more about Schedule A cases →Frequently Asked Questions
The case involved U.S. Design Patent USD966499S (application no. US29/820440), protecting the ornamental design of an electric water flosser.
The Northern District of Illinois is a frequently chosen forum for Schedule A enforcement actions due to its procedural efficiency in handling multi-defendant IP cases and its established practice of issuing early TROs and asset freeze orders.
It reinforces that design patents are enforceable assets in the personal care technology space and signals continued enforcement risk for marketplace sellers sourcing visually similar products without conducting design patent clearance.
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References
- United States District Court, Northern District of Illinois — Case 1:23-cv-06434
- U.S. Patent and Trademark Office — Design Patent USD966499S
- World Intellectual Property Organization — Industrial Design Protection
- Cornell Legal Information Institute — 35 U.S.C. § 289
- PatSnap — IP Intelligence Solutions for E-Commerce Sellers
This article is for informational purposes only and does not constitute legal advice. All case information is drawn from publicly available court records. For platform capabilities, visit PatSnap.