Maxx Group LLC v. Dbest Products Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Maxx Group, LLC (California)
  • Defendant: Dbest Products, Inc. (California)
  • Plaintiff's Counsel: Rhema Law Group, P.C.
• Case Identification: 8:26-cv-01257, C.D. Cal., 05/19/2026
• Venue Allegations: Venue is alleged to be proper in the Central District of California based on Defendant's business and enforcement activities within the district.
• Core Dispute: Plaintiff seeks a declaratory judgment that its collapsible cart products do not infringe Defendant's patent on collapsible carts, and further seeks damages and injunctive relief related to Defendant's enforcement actions on the Amazon marketplace.
• Technical Context: The dispute concerns the mechanical design of collapsible, wheeled utility carts, a common consumer product where portability and structural rigidity are key features.
• Key Procedural History: The complaint alleges a notable history where Defendant previously filed an infringement complaint with Amazon in March 2024 regarding the same patent and similar products, which Defendant then withdrew in May 2024 after Plaintiff provided non-infringement evidence. The current lawsuit arises from a new Amazon infringement complaint filed by Defendant in April 2026 against the same products, forming the basis for Plaintiff's estoppel and bad-faith allegations.

Case Timeline

Date	Event
2020-01-06	U.S. Patent No. 11,338,835 Priority Date
2022-05-24	U.S. Patent No. 11,338,835 Issue Date
2024-03-21	Defendant files initial infringement complaint with Amazon
2024-04-22	Plaintiff sends appeal request to Amazon
2024-04-26	Plaintiff sends non-infringement claim chart to Defendant's counsel
2024-05-01	Defendant withdraws its 2024 Amazon complaint
2026-04-15	Defendant files new infringement complaint with Amazon
2026-04-21	Correspondence between parties regarding new Amazon complaint
2026-05-19	Complaint for Declaratory Judgment filed

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 11,338,835 - "High Load Capacity Collapsible Carts" (May 24, 2022)

The Invention Explained

• Problem Addressed: The patent notes that due to the collapsible nature of prior art carts, their sidewalls "may not be sufficiently sturdy to allow for transporting heavy objects" '835 Patent, col. 2:9-12
• The Patented Solution: The invention is a collapsible cart with sidewalls constructed from multiple hinged panels that fold inward. To enhance rigidity when open, the design incorporates one or more "slideable members" that move along tracks spanning the hinged panels. These members are designed to move between an "open position," allowing the walls to fold, and a "closed position," where they lock the panels together to create a rigid structure '835 Patent, abstract '835 Patent, col. 4:50-66 Figure 1 of the patent illustrates these slideable members (58, 60) positioned along tracks on the cart's sidewalls '835 Patent, FIG. 1
• Technical Importance: The described solution aims to provide the market with a utility cart that offers the storage convenience of a folding design without compromising the structural integrity required for carrying heavy loads.

Key Claims at a Glance

• The complaint seeks a declaratory judgment of non-infringement of the '835 Patent, referencing independent claims 1, 9, and 17 Compl. ¶25
• Independent Claim 1 includes the following essential elements:
  • A rigid frame forming a compartment with a front wall, a rear wall, a right sidewall, a left sidewall, and a bottom wall, where the sidewalls are comprised of hinged panels.
  • A rotatable base panel coupled to the bottom wall.
  • A first track formed along the first and second panels of the right sidewall.
  • A first slideable member cooperatively engaged to the first track, movable between an open position (to allow folding) and a closed position (to lock the panels).
• The complaint does not explicitly reserve rights to assert dependent claims, but seeks a declaration that the accused products do not infringe "any claim" of the patent Compl. ¶27 Compl. ¶16:3

III. The Accused Instrumentality

Product Identification

• The accused instrumentalities are Plaintiff MAXX's "collapsible cart products" sold on the Amazon platform, identified by ASINs including B0CWPB8Q2X and B0CBJNC21R Compl. ¶8 Compl. ¶25

Functionality and Market Context

• The complaint describes the accused products as collapsible carts Compl. ¶8 A visual in the complaint juxtaposes a figure from the '835 patent with photographs of the accused MAXX product, highlighting the components central to the dispute Compl. p. 7
• Critically, the complaint alleges that the accused products do not contain the "slideable members" required by the patent claims. Instead, they allegedly use a "pair of removable members... from the bottom wall that are used to snap onto the tracks of the first & second panels to lock the panels into place" Compl. p. 8
• The complaint alleges that these products are sold on Amazon and that Defendant's takedown notices have resulted in delistings, lost sales, and damage to Plaintiff's business, suggesting their commercial significance Compl. ¶17

IV. Analysis of Infringement Allegations

'835 Patent Infringement Allegations

Claim Element (from Independent Claim 1)	Alleged Non-Infringing Functionality (per Plaintiff)	Complaint Citation	Patent Citation
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 allow the right sidewall to fold inwardly, to a closed position to selectively lock the first right panel to the second right panel...	The accused products do not contain any "slideable members." They instead utilize separate, "removable members" that are stored in the bottom wall and "snap onto the tracks" to lock the panels, rather than sliding along them.	¶8; ¶25	col. 4:50-58
...wherein the first slideable member is in the open position when disposed along the first track adjacent the first position of the first track... and is in the closed position when disposed along the first track adjacent the second position of the first track while being disposed across both the first right panel and second right panel.	The accused product's locking mechanism is a completely separate part that is not "disposed along the first track" at all times. It is attached for locking and detached for folding, which is alleged to be a fundamentally different operation.	¶8; ¶13	col. 7:5-13

• Identified Points of Contention:
  • Scope Questions: The central dispute appears to be one of claim scope. The complaint raises the question of whether the term "slideable member" can be interpreted to read on the accused product's "removable snap-on members" Compl. p. 8 Plaintiff argues that it cannot, either literally or under the doctrine of equivalents, because the accused product's component is entirely absent, precluding an element-by-element match Compl. ¶13
  • Technical Questions: The case presents a technical question about the mechanism of action. What evidence will be required to show whether the accused product's "snap-on" locking function is or is not substantially different from the claimed function of a "slideable member" that is "movable along the first track"? Compl. ¶13 '835 Patent, col. 7:2-3

V. Key Claim Terms for Construction

The complaint's non-infringement theory focuses almost exclusively on the following term.

• The Term: "slideable member"
• Context and Importance: This term appears to be dispositive. The plaintiff's entire non-infringement argument is premised on the assertion that its products lack this specific element Compl. ¶25 Compl. p. 8 Practitioners may focus on this term because its construction will likely determine the outcome of the literal infringement analysis and frame the debate for the doctrine of equivalents.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: A party arguing for a broader scope might point to the patent's abstract, which refers more generally to "fastening mechanisms," and could argue that "slideable member" is merely one exemplary embodiment '835 Patent, abstract
  • Evidence for a Narrower Interpretation: The claim language itself describes the member as "movable along the first track" '835 Patent, col. 7:2-3 The detailed description reinforces this, stating the member moves "between an open position... to a closed position" while remaining engaged with the track '835 Patent, col. 4:53-58 This language may support an interpretation that the member must be continuously engaged with the track, which would exclude a fully removable component.

VI. Other Allegations

• Indirect Infringement: Not applicable, as this is an action for a declaratory judgment of non-infringement.
• Willful Infringement: The complaint's posture is reversed, alleging that Defendant's enforcement actions constitute knowing and bad-faith assertion of the patent against a non-infringing product Compl. ¶20 Compl. ¶30 The primary factual basis for this allegation is that Defendant previously withdrew an Amazon complaint in 2024 after being presented with Plaintiff's non-infringement arguments, but then re-filed a similar complaint in 2026, suggesting knowledge that the products were not infringing Compl. ¶¶11-16 These allegations also support claims for tortious interference and violations of the Lanham Act (Compl. ¶¶20; Compl. ¶53). The complaint also asserts a claim of estoppel based on these same facts Compl. ¶¶56-65

VII. Analyst's Conclusion: Key Questions for the Case

This case appears to center on two primary questions for the court:

• A core issue will be one of definitional scope: can the claim term "slideable member," which the patent describes as being "movable along... a track," be construed to cover the accused product's "removable members," which allegedly "snap onto the tracks" from a separate location?
• A key equitable and procedural question will be one of estoppel: did the Defendant's voluntary withdrawal of its initial 2024 Amazon complaint, after receiving Plaintiff's non-infringement analysis, constitute a representation that induced reasonable reliance by the Plaintiff, thereby legally barring Defendant from re-asserting infringement against the same products two years later?