DCT
2:25-cv-11331
Dbest Products Inc v. Guangdong Haixing Plastic & Rubber Co Ltd
Key Events
Complaint
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Dbest Products, Inc. (California)
- Defendant: Guangdong Haixing Plastic & Rubber Co., Ltd. (China)
- Plaintiff’s Counsel: Orbit IP, LLP
- Case Identification: 2:25-cv-11331, C.D. Cal., 11/25/2025
- Venue Allegations: Plaintiff alleges venue is proper because Defendant is subject to personal jurisdiction in the district, has consented to jurisdiction, and does substantial business there.
- Core Dispute: Plaintiff alleges that Defendant’s portable, collapsible carts infringe two patents related to locking mechanisms that enhance the structural integrity of the carts' sidewalls.
- Technical Context: The technology pertains to collapsible utility carts, a mature consumer product category where innovations in sturdiness, load capacity, and ease of use are key market differentiators.
- Key Procedural History: The complaint alleges that Plaintiff has a policy of marking its patented products, a fact that may become relevant to issues of notice and potential damages.
Case Timeline
| Date | Event |
|---|---|
| 2020-01-06 | Earliest Priority Date for ’446 and ’546 Patents |
| 2025-04-15 | U.S. Patent No. 12,275,446 Issues |
| 2025-05-20 | U.S. Patent No. 12,304,546 Issues |
| 2025-11-25 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 12,275,446, "High Load Capacity Collapsible Carts," issued Apr. 15, 2025
The Invention Explained
- Problem Addressed: The patent's background section notes that prior art collapsible carts often have sidewalls that "may not be sufficiently sturdy to allow for transporting heavy objects" due to their collapsible design (’446 Patent, col. 2:13-16).
- The Patented Solution: The invention addresses this by constructing the cart's sidewalls from multiple panels that fold relative to one another. To provide rigidity when the cart is open, the patent describes a locking mechanism consisting of a "track" that spans across two adjacent panels and a "slideable member" that moves along this track. When the slideable member is moved into a closed position, it bridges the two panels, locking them into a single, sturdy plane. (’446 Patent, Abstract; col. 5:9-32). Figure 2 illustrates this concept, showing the first right panel (26) and second right panel (28) which are locked together by the slideable member (58) moving along the track (46).
- Technical Importance: This design aims to combine the storage convenience of a collapsible cart with the structural integrity of a rigid cart, overcoming a common trade-off in the field. (’446 Patent, col. 1:19-23).
Key Claims at a Glance
- The complaint asserts at least one claim of the ’446 Patent (Compl. ¶15). Independent Claim 1 is representative and includes the following essential elements:
- A collapsible cart with a rigid frame forming a compartment.
- The right sidewall comprises a first right panel rotatably coupled to a second right panel.
- A "first track" is formed along both the first and second right panels.
- A "first slideable member" is engaged with the track and is movable between an open position and a closed position.
- In the closed position, the slideable member is "disposed across both the first right panel and second right panel" to selectively lock them together.
U.S. Patent No. 12,304,546, "Collapsible Carts," issued May 20, 2025
The Invention Explained
- Problem Addressed: Similar to the ’446 Patent, this patent addresses the structural weakness of prior art collapsible cart sidewalls, which limits their utility for carrying heavy items (’546 Patent, col. 2:23-28).
- The Patented Solution: The invention describes a collapsible cart where at least one of the folding sidewalls is composed of a first panel rotatably coupled to a second panel. To secure these panels, the patent claims a "first latch part" on the edge of the first panel and a "second latch part" on the edge of the second panel. These latch parts are configured to "mate with one another" to hold the two panels "in a common plane" when the cart is in its open, expanded state. (’546 Patent, col. 13:32-47). This provides the necessary rigidity for the sidewall.
- Technical Importance: The invention purports to offer a robust collapsible cart design by ensuring that the multi-panel sidewalls can be securely locked into a flat, load-bearing configuration. (’546 Patent, col. 2:23-28).
Key Claims at a Glance
- The complaint asserts at least one claim of the ’546 Patent (Compl. ¶20). Independent Claim 1 is representative and includes the following essential elements:
- A collapsible cart with a frame defining a compartment, with at least three walls configured to fold inwardly.
- One of the opposing walls consists of a first panel and a second panel that is rotatably coupled to the first.
- A "first latch part" is disposed on an edge of the first panel.
- A "second latch part" is disposed on an edge of the second panel.
- The first and second latch parts are configured to mate to hold the panels in a common plane.
III. The Accused Instrumentality
- Product Identification: The complaint identifies the accused instrumentalities as "numerous products" sold by Defendant on Amazon.com, collectively referred to as the "Accused Products" (Compl. ¶13).
- Functionality and Market Context: The Accused Products are described as collapsible carts (Compl. ¶13). The complaint alleges that these products are sold to consumers in the United States and within the Central District of California (Compl. ¶11). The complaint references an attached schedule of Amazon Standard Identification Numbers (ASINs) for each Accused Product, but this exhibit was not included with the complaint document (Compl. ¶13, Ex. C).
IV. Analysis of Infringement Allegations
No probative visual evidence provided in complaint.
The complaint alleges that Defendant directly infringes the patents-in-suit by "offering for sale, selling, and/or otherwise distributing the Accused Products" (Compl. ¶¶15, 20). The complaint references representative claim charts in Exhibits D and E, which were not provided with the complaint document (Compl. ¶15, ¶20). The narrative infringement theory is summarized below based on the asserted claims.
’446 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A collapsible cart configured to transition from a closed condition... to an open condition... comprising: a rigid frame forming a compartment... | The complaint alleges the Accused Products are collapsible carts with a rigid frame. | ¶13, ¶15 | col. 4:46-48 |
| the right sidewall comprising a first right panel rotatably coupled to a second right panel; | The complaint alleges the Accused Products have a sidewall made of at least two panels joined by a hinge. | ¶15 | col. 4:49-51 |
| a first track formed along the first right panel and the second right panel... | The complaint alleges the Accused Products feature a track spanning the two panels of the sidewall. | ¶15 | col. 5:9-15 |
| a first slideable member cooperatively engaged to the first track... movable... to selectively lock the first right panel to the second right panel... | The complaint alleges the Accused Products utilize a sliding component that moves along the track to lock the sidewall panels together. | ¶15 | col. 5:16-24 |
- Identified Points of Contention:
- Scope Questions: A central question may be whether the mechanism on the Accused Products constitutes a "track" and "slideable member" as contemplated by the patent. The dispute could focus on whether the accused mechanism involves one component sliding along a defined path on another, or if it operates differently (e.g., as a simple snap-fit clip).
- Technical Questions: The analysis will likely require evidence of how the accused locking mechanism operates. The question for the court will be whether the functionality of the accused device maps onto the specific structural and functional requirements of the "track" and "slideable member" limitations.
’546 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A collapsible cart... comprising: a frame defining a compartment... with at least three of the walls configured to rotatably fold inwardly... | The complaint alleges the Accused Products are collapsible carts whose walls fold inward for storage. | ¶13, ¶20 | col. 13:21-28 |
| one of the two opposing walls consists of a first panel and a second panel; and the second panel rotatably coupled to the first panel; | The complaint alleges the Accused Products have a sidewall made of two hinged panels. | ¶20 | col. 13:30-32 |
| a first latch part disposed on an edge of the first panel... and a second latch part disposed on an edge of the second panel... | The complaint alleges the Accused Products have corresponding latching components on the edges of the hinged panels. | ¶20 | col. 13:33-37 |
| wherein the first latch part and the second latch part are configured to mate... and hold the first and second panels in a common plane... | The complaint alleges that the latching components on the Accused Products engage to secure the panels into a flat, rigid wall. | ¶20 | col. 13:38-44 |
- Identified Points of Contention:
- Scope Questions: The term "latch part" is not explicitly defined in the patent. This raises the question of its scope: does it cover any pair of mating components that secure the panels, or does the context of the patent imply a more specific type of mechanical latch?
- Technical Questions: Evidence will be needed to show whether the connecting components on the Accused Products are "disposed on an edge" of the panels and whether they "mate" in a way that holds the panels "in a common plane," as required by the claim.
V. Key Claim Terms for Construction
’446 Patent
- The Term: "a first slideable member cooperatively engaged to the first track"
- Context and Importance: This phrase describes the core locking mechanism of Claim 1. The outcome of the infringement analysis for this patent will likely depend heavily on whether the Defendant's products are found to have this specific structure.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The claim language does not restrict the "slideable member" or "track" to a specific shape, size, or material, which may support a construction that covers functionally similar mechanisms.
- Evidence for a Narrower Interpretation: The specification consistently describes and illustrates this feature in a specific way, showing a sliding piece (58) moving within a defined channel (46) that extends across the two panels (26, 28) (’446 Patent, col. 5:9-32; Fig. 2). A party might argue that the term should be limited to such an embodiment where one component physically slides along a guide path on another.
’546 Patent
- The Term: "latch part"
- Context and Importance: This term is central to defining the locking mechanism in Claim 1 of the ’546 Patent. Its construction will determine whether a wide or narrow range of panel-fastening technologies fall within the claim's scope. Practitioners may focus on this term because its apparent breadth could be a key point of dispute.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The term "latch" is a common mechanical term. A party could argue for its plain and ordinary meaning, which would encompass a wide variety of mechanisms that fasten or secure objects together.
- Evidence for a Narrower Interpretation: While the patent does not provide an explicit definition, it states the function of the mated latch parts is to "hold the first and second panels in a common plane" (’546 Patent, col. 13:43-44). A party could argue this functional requirement limits the term to mechanisms that provide structural rigidity and alignment, excluding, for example, simple hooks or fasteners that do not enforce planarity.
VI. Other Allegations
- Willful Infringement: The complaint alleges entitlement to enhanced damages for willful infringement (Compl. ¶¶18, 23). The stated basis for this claim is Plaintiff's policy of marking its products with the relevant patent numbers, which allegedly provides notice to the public, including Defendant (Compl. ¶10).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of mechanical specificity: does the mechanism used to secure the foldable sidewalls on the Accused Products meet the specific claim limitations of a "slideable member" moving along a "track" as required by the ’446 Patent, or is it a different type of connection?
- A second primary issue will be one of definitional scope: can the general term "latch part" in the ’546 Patent be construed broadly to read on the specific fastening components used in the Accused Products, or will its meaning be narrowed by the functional requirements described in the patent's specification?
- A key evidentiary question will be what proof Plaintiff offers to demonstrate that the Accused Products, sold by a foreign entity on a third-party marketplace, practice each and every element of the asserted claims. The analysis will depend on detailed evidence of the Accused Products' construction and operation.