dbest Products v. Luoyang Muzhou: Portable Cart Patent Suit Dismissed With Prejudice
dbest Products, Inc. asserted two portable cart patents — US12275446B2 and US12304546B1 — against Chinese retailer Luoyang Muzhou in the Central District of California. The plaintiff voluntarily dismissed the action with prejudice just 99 days after filing, closing off any future re-filing on the same claims.
Early exit: dbest’s portable cart suit ends with prejudice in 99 days
On May 21, 2025, dbest Products, Inc. — a U.S. portable cart manufacturer — filed an infringement action in the Central District of California against Luoyang Muzhou Department Store Sales Co., Ltd., a Chinese department store sales company. The complaint asserted two patents, US12275446B2 and US12304546B1, both covering portable cart designs and technology. The case was assigned to the Central District court, with Orbit IP LLP representing the plaintiff.
On August 27, 2025, just 99 days after filing, dbest Products filed a Notice of Dismissal under Fed. R. Civ. P. 41(a)(1). The court accepted the notice, vacated all pending dates and deadlines, and formally dismissed the action with prejudice. A with-prejudice dismissal is a final disposition — dbest is barred from re-filing the same claims against Luoyang Muzhou based on these two patents. No defendant counsel appeared on the public record, suggesting the case resolved before Luoyang Muzhou formally engaged in the proceedings.
The 99-day timeline is notably short for a patent infringement action, and the with-prejudice designation — chosen by the plaintiff itself — suggests a deliberate, negotiated exit rather than a simple administrative withdrawal. What drove the resolution remains unknown from the public record: a licensing agreement, a settlement with undisclosed terms, or a business decision to discontinue enforcement are all consistent with the facts. The absence of defendant counsel on record may indicate the matter was resolved through direct commercial channels rather than formal litigation engagement.
Filing to Voluntary dismissal in 99 days
99 days — resolved before any substantive court rulings issued
Dismissed with prejudice: what the voluntary exit means for both parties
Rule 41(a)(1) dismissal with prejudice explained
Fed. R. Civ. P. 41(a)(1) allows a plaintiff to voluntarily dismiss an action by filing a notice before the defendant serves an answer or a motion for summary judgment. Ordinarily such a dismissal is without prejudice, but here the court ordered dismissal with prejudice — meaning the plaintiff elected or agreed to the more final outcome. The result carries the force of a judgment on the merits: the same claims cannot be re-litigated.
Final — no re-filing permitteddbest Products: patent rights survive but claims are extinguished here
A with-prejudice dismissal does not invalidate dbest’s patents — US12275446B2 and US12304546B1 remain in force and enforceable against third parties. However, dbest has permanently waived the right to sue Luoyang Muzhou on these specific claims. This outcome is consistent with a negotiated resolution: dbest may have obtained a licence, royalty, or product withdrawal in exchange for the voluntary dismissal, though no such terms appear in the public record.
Patents intact; this defendant releasedLuoyang Muzhou: protected from future suit on these patents
Luoyang Muzhou benefits from a permanent bar against dbest re-asserting these two patents for the same accused conduct. No defendant counsel appeared in the public record, which suggests the Chinese retailer either reached a direct commercial arrangement with dbest or was not formally served before the dismissal was filed. Either way, the with-prejudice order provides Luoyang Muzhou strong protection against re-litigation of these specific claims.
Claim-barred; no liability foundPortable cart IP enforcement: what this swift exit signals
The 99-day lifecycle and with-prejudice exit together suggest dbest Products is actively using its patent portfolio as a commercial negotiation tool against Chinese import competitors. Other portable cart importers selling in the U.S. market should note that dbest holds two issued utility patents and has demonstrated willingness to file suit. The swift resolution may reflect a repeatable enforcement strategy: file, negotiate, dismiss — leaving the patents intact for the next target.
Active enforcement postureFull party and counsel information
| Role | Name | Type | Detail |
|---|---|---|---|
| Plaintiff | dbest products, Inc. | Company | Portable cart manufacturer — holder of US12275446B2 and US12304546B1Search in Eureka ↗ |
| Defendant | Luoyang Muzhou Department Store Sales Co., Ltd. | Company | Chinese department store sales company selling portable cart productsSearch in Eureka ↗ |
| Plaintiff counsel | Bruce G. Chapman | Attorney | Counsel for dbest products, Inc.Search in Eureka ↗ |
| Plaintiff counsel | David A. Randall | Attorney | Counsel for dbest products, Inc.Search in Eureka ↗ |
| Plaintiff counsel | Ehab M. Samuel | Attorney | Counsel for dbest products, Inc.Search in Eureka ↗ |
| Plaintiff law firm | Orbit IP LLP | Law Firm | Representing dbest products, Inc.Search in Eureka ↗ |
| Presiding judge | Judge N/A | Judge | California Central District CourtSearch in Eureka ↗ |
Official order — verbatim text
The court’s order reflects a straightforward acceptance of the plaintiff’s Rule 41(a)(1) notice, with the critical addition of a with-prejudice designation. The phrasing — ‘finding good cause therefor’ — indicates judicial endorsement of the finality chosen by the plaintiff, not a contested ruling. For dbest, the order confirms the patents remain valid and enforceable while extinguishing only this defendant’s exposure. For Luoyang Muzhou, the order functions as a permanent shield against re-assertion of these specific claims by dbest.
US12275446B2 & US12304546B1 — Portable cart mechanical designs
US12275446B2 and US12304546B1 are both issued U.S. utility patents assigned to dbest Products, Inc., covering portable cart technology. The patents’ application numbers — US18/460131 and US19/032431 respectively — indicate relatively recent prosecution histories, consistent with dbest building a current, commercially relevant portfolio rather than relying on legacy IP. Portable cart patents in this class typically protect structural features such as folding mechanisms, load-bearing frames, handle assemblies, and wheel configurations that distinguish one product from commodity alternatives.
For a company competing in a market dominated by low-cost Chinese manufacturing, owning two issued utility patents on portable cart design provides meaningful leverage. Enforcement actions against importers — particularly those selling through e-commerce channels — are a recognised strategy for U.S. product brands seeking to defend shelf space and margins. The existence of two overlapping patents on similar technology suggests dbest has deliberately constructed a portfolio with redundant protection, making design-arounds more difficult for competitors and raising the cost of non-compliance.
Should you run an FTO against US12275446B2 and US12304546B1?
Any company importing, manufacturing, or selling portable carts in the U.S. market — including e-commerce sellers, private-label brands, wholesale distributors, and fulfilment operations — should assess freedom to operate against dbest’s issued patent portfolio. This case confirms dbest is actively enforcing these patents and is prepared to file in the Central District of California, a well-resourced venue with experience in product IP disputes. The swift resolution of this case does not reduce the risk to other market participants.
PatSnap Eureka’s FTO Search Agent can map the claims of US12275446B2 and US12304546B1 against your product specifications, identify design-around opportunities, and surface any related continuations or pending applications that could extend dbest’s coverage. Eureka’s litigation monitoring tools also allow R&D and legal teams to track new enforcement filings by dbest Products in real time, providing early warning before a complaint is served.
Run a freedom-to-operate analysis on US12275446B2 to assess your product’s exposure
Run FTO in Eureka →Similar portable cart patent infringement cases in U.S. district courts
Explore comparable patent infringement actions involving portable cart and consumer product IP asserted against Chinese importers in the Central District of California.
What this case signals for the portable cart IP landscape
A 99-day with-prejudice dismissal against a Chinese importer suggests a deliberate, portfolio-driven enforcement strategy rather than a one-off dispute.
dbest’s two-patent portfolio creates a credible enforcement floor
With two recently issued patents on portable cart designs, dbest Products has established a meaningful IP position in a market heavily supplied by Chinese manufacturers. The swift voluntary dismissal — with prejudice — is consistent with a licensing-first strategy: assert, negotiate, resolve. Competitors and importers in this space should treat these patents as live enforcement risks.
No defendant counsel on record signals a pre-appearance resolution
Luoyang Muzhou never formally appeared, and no defence law firm is listed in the public record. This pattern typically signals either a direct commercial settlement reached outside formal litigation channels, or that the defendant was not fully served before the dismissal. Either scenario shortens the enforcement cycle and reduces plaintiff costs — a model that may be replicated against other targets.
dbest v Luoyang — key questions answered
A with-prejudice dismissal means dbest Products has permanently waived the right to sue Luoyang Muzhou on the same patent claims. The patents US12275446B2 and US12304546B1 remain valid, but dbest cannot re-file this specific action against this defendant. The court accepted the plaintiff’s Rule 41(a)(1) notice and entered the dismissal with prejudice on August 27, 2025.
dbest Products asserted two utility patents: US12275446B2 (application US18/460131) and US12304546B1 (application US19/032431). Both patents cover portable cart technology. The case was filed in the Central District of California on May 21, 2025, and dismissed after 99 days.
The public record does not disclose the reason. A with-prejudice voluntary dismissal typically suggests the plaintiff received something of value — a licence, a product withdrawal, or a settlement payment — in exchange for foregoing the right to re-file. The absence of defendant counsel on the docket suggests the matter may have been resolved through direct commercial negotiation rather than formal litigation proceedings.
No. A voluntary dismissal with prejudice terminates the litigation but has no effect on patent validity. US12275446B2 and US12304546B1 remain issued and enforceable. dbest retains the right to assert both patents against other parties accused of infringement. The dismissal only extinguishes claims against Luoyang Muzhou specifically.
The risk remains live. dbest Products has demonstrated willingness to file patent infringement actions in the Central District of California against Chinese portable cart sellers. The two asserted patents are recently issued, suggesting active portfolio maintenance. Importers, e-commerce sellers, and distributors of portable carts selling in the U.S. market should conduct freedom-to-operate analysis against dbest’s portfolio before or during product launch.
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