DCT
2:25-cv-00584
Shanghai Yiyuren Technology Co Ltd v. Dbest Products Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Shanghai Yiyuren Technology Co., Ltd. (China)
- Defendant: Dbest Products, Inc. (California)
- Plaintiff’s Counsel: Miller Law Associates, APC; Norris McLaughlin P.A.
- Case Identification: 2:25-cv-00584, C.D. Cal., 04/18/2025
- Venue Allegations: Plaintiff alleges venue is proper in the Central District of California because Defendant is a California corporation domiciled in the district and has engaged in relevant acts and omissions within the district.
- Core Dispute: Plaintiff seeks a declaratory judgment that its folding storage containers do not infringe Defendant’s patent related to stackable, collapsible carts, following Defendant’s use of the patent to have Plaintiff’s products delisted from an online marketplace.
- Technical Context: The technology relates to consumer-grade collapsible carts and containers, a market where product design focuses on maximizing strength and portability while minimizing storage space.
- Key Procedural History: The complaint alleges that on or around December 20, 2024, Defendant initiated a patent infringement complaint with Amazon, causing Plaintiff’s products to be removed from the marketplace. The complaint also identifies a portfolio of prior art that it alleges the U.S. Patent and Trademark Office did not consider during prosecution of the patent-in-suit, including a third-party submission made against a predecessor application.
Case Timeline
| Date | Event |
|---|---|
| 2020-01-06 | Earliest Priority Date for ’576 Patent |
| 2024-10-01 | ’576 Patent Issued |
| 2024-12-20 | Alleged Takedown of Plaintiff's Products on Amazon |
| 2025-04-18 | Complaint for Declaratory Judgment Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 12,103,576 - "STACKABLE COLLAPSIBLE CARTS"
- Patent Identification: U.S. Patent No. 12,103,576, “STACKABLE COLLAPSIBLE CARTS,” issued October 1, 2024 (’576 Patent).
The Invention Explained
- Problem Addressed: The patent’s background section notes that in prior art collapsible carts, "the sidewalls may not be sufficiently sturdy to allow for transporting heavy objects" (’576 Patent, col. 1:21-23).
- The Patented Solution: The invention is a collapsible cart designed for improved sturdiness. It features sidewalls that fold inward, with at least one sidewall constructed from two separate panels: a larger outer panel with an opening and a smaller inner panel that fits within that opening (’576 Patent, Abstract; col. 11:46-52). To enhance rigidity when the cart is open, the design incorporates a "first lock assembly" with a "slideable member" that moves along a "track" spanning both panels, selectively locking them together into a solid wall (’576 Patent, col. 2:41-50).
- Technical Importance: This two-panel, track-and-lock design for the sidewalls aims to provide the structural integrity of a fixed-wall cart while retaining the storage convenience of a fully collapsible one.
Key Claims at a Glance
- The complaint identifies independent claims 1, 11, and 15 as being at issue (Compl. ¶30).
- Independent Claim 1:
- A collapsible cart with a rigid frame and sidewalls configured to fold inwardly.
- The right sidewall comprises a first right panel rotatably coupled to a second right panel, with the second panel proportioned to fit within an opening in the first.
- 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 to selectively lock the first right panel to the second right panel.
- Independent Claim 11:
- A cart with a rigid frame and a right sidewall comprising first, second, and third panels.
- The second and third panels collectively cover an opening in the first panel.
- The second right panel comprises a "ribbed wall with a plurality of ribs."
- A "first lock assembly" is integrated with the first and second right panels, having conditions for locking and unlocking the panels.
- Independent Claim 15:
- A stackable collapsible cart with a right sidewall having a first panel rotatably coupled to a second panel.
- A "first lock assembly" integrated with the panels.
- A "wheel assembly" coupled to the bottom wall having a "first vertical axis."
- A rigid top cover with an "indentation pattern" aligned with the wheel assembly's vertical axis, configured to receive the wheel assembly of an identical cart when stacked.
III. The Accused Instrumentality
Product Identification
- The "Uamfuri Products," which are described as "folding storage boxes" sold on the Amazon marketplace (Compl. ¶¶ 2, 4).
Functionality and Market Context
- The complaint describes the Uamfuri Products as competing in the "folding storage boxes area" and identifies the Amazon marketplace as Plaintiff's primary sales channel in the United States (Compl. ¶4). The complaint includes an image showing two models of what appear to be multi-drawer plastic storage units on wheels (Compl. p. 2). Plaintiff's central allegation is that these products achieve their collapsibility through a design that is fundamentally different from and lacks the key structural elements recited in the ’576 Patent’s claims (Compl. ¶31).
IV. Analysis of Infringement Allegations
The complaint seeks a declaratory judgment of non-infringement. The following tables summarize the Plaintiff's allegations regarding why its products do not meet certain limitations of the asserted independent claims.
’576 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Non-Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a first track formed along the first right panel and the second right panel extending from a first position on the first right panel to a second position on the second right panel | Plaintiff alleges this feature is absent from the Accused Products. | ¶31 | col. 11:53-58 |
| a first slideable member cooperatively engaged to the first track, the first slideable member is movable along the first track between an open position to a closed position to selectively lock the first right panel to the second right panel | Plaintiff alleges this feature is absent from the Accused Products. | ¶31 | col. 11:59-67 |
’576 Patent Infringement Allegations
| Claim Element (from Independent Claim 11) | Alleged Non-Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| the second right panel comprises a ribbed wall with a plurality of ribs | Plaintiff alleges this feature is absent from the Accused Products. | ¶31 | col. 13:1-3 |
| a first lock assembly integrated with the first right panel and the second right panel, the first lock assembly having a first condition for locking the first right panel to the second right panel, and a second condition for unlocking the first right panel from the second right panel | Plaintiff alleges this feature is absent from the Accused Products. | ¶32 | col. 13:4-10 |
Identified Points of Contention
- Factual Questions: The primary dispute appears to be factual: do the Uamfuri Products contain the specific structural components recited in the claims? The complaint advances a theory of non-infringement based on the literal absence of claimed elements such as a "first track," a "slidable member," and a "lock assembly" (Compl. ¶¶ 31-32).
- Scope Questions: This factual dispute raises underlying questions of claim scope. For example, if the accused products have a mechanism for holding their panels in place, the court may need to decide whether that mechanism constitutes a "lock assembly" as that term is used in the patent, or if the term is limited to the specific sliding and latching embodiments disclosed in the specification.
V. Key Claim Terms for Construction
The Term: "first track"
- Context and Importance: Plaintiff alleges its products lack a "first track" (Compl. ¶31). The definition of this term will be central to determining whether any guide, groove, or channel on the accused product meets this limitation. Practitioners may focus on this term because its construction could determine whether the claim reads on a wider variety of panel-stiffening mechanisms or is limited to the specific embodiment shown.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent does not provide an explicit definition of "track," which may support an argument for applying its plain and ordinary meaning as a path or guide along which something moves.
- Evidence for a Narrower Interpretation: The specification describes the track as extending "across the first vertical axis" connecting the two panels, and figures such as FIG. 42B depict it as a distinct C-shaped channel designed to retain a slideable member (’576 Patent, col. 6:65-67; FIG. 42B). This could support an argument that the term is limited to such a structure.
The Term: "lock assembly"
- Context and Importance: This term appears in independent claims 11 and 15, and Plaintiff alleges its products lack it (Compl. ¶32). The dispute will likely center on whether any fastening component on the accused product can be characterized as the claimed "lock assembly."
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The claim language is partly functional, describing the assembly as having a "condition for locking" and a "condition for unlocking" the panels (’576 Patent, col. 13:6-9). This may support a construction that covers any mechanism capable of performing this function.
- Evidence for a Narrower Interpretation: The specification discloses specific embodiments, including a "slideable member 58" that engages a "peg 42B" (’576 Patent, col. 9:22-30) and an integrated lock (65) for the top cover (’576 Patent, FIG. 55). A party could argue these specific examples limit the scope of the more general term "lock assembly."
VI. Other Allegations
The complaint includes allegations of anticompetitive behavior and patent misuse against the Defendant. It alleges that Defendant's "use of the '576 Patent to dominate the market for folding storage containers is both wrongful and targeted to competitively harm Plaintiff" (Compl. ¶16). These allegations are based on the Defendant's actions in using the patent to delist Plaintiff’s products from Amazon, which Plaintiff frames as an "abuse of the patent laws" (Compl. ¶1).
VII. Analyst’s Conclusion: Key Questions for the Case
- A central issue will be one of structural presence and equivalence: do the accused "Uamfuri Products" contain physical structures that literally meet the claim limitations of a "track," "slidable member," and "lock assembly," or, if not, do they contain equivalent structures that perform the same function in substantially the same way to achieve the same result?
- The case will also likely involve a question of definitional scope: will the court construe key terms like "track" and "lock assembly" broadly based on their plain meaning and functional descriptions, or narrowly based on the specific structural embodiments detailed in the patent's specification and figures?
- A parallel question for the court will concern enforcement conduct: separate from the technical infringement analysis, did the defendant's use of its patent in communications with a third-party marketplace, allegedly with knowledge of invalidating prior art, constitute actionable patent misuse or unfair competition?