DCT

4:25-cv-01171

Chen v. Dollarsign Ltd

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Key Events
Complaint

I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 4:25-cv-01171, E.D. Tex., 10/24/2025
  • Venue Allegations: Plaintiff alleges venue is proper because Defendant is a foreign entity not residing in the United States and may therefore be sued in any judicial district.
  • Core Dispute: Plaintiff alleges that Defendant’s magnetic building block toys infringe two U.S. patents related to the internal structure and magnetic assembly methods that allow for more versatile connections.
  • Technical Context: The technology resides in the popular and competitive market for magnetic construction toys, where innovation often centers on improving the strength, stability, and variety of inter-block connections.
  • Key Procedural History: The complaint notes that U.S. Patent No. 12,151,182 is a continuation-in-part of the application that matured into U.S. Patent No. 11,766,622, indicating a shared technical disclosure and establishing a connected patent family.

Case Timeline

Date Event
2022-12-28 Earliest Priority Date Asserted ('622 & '182 Patents)
2023-09-26 U.S. Patent No. 11,766,622 Issues
2024-10-01 Alleged Infringement Begins (approx.)
2024-10-18 Alleged Date of Knowledge for Willfulness
2024-11-26 U.S. Patent No. 12,151,182 Issues
2025-10-24 Complaint Filed

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

U.S. Patent No. 11,766,622 - MAGNETIC SUCTION BUILDING BLOCK

  • Patent Identification: U.S. Patent No. 11,766,622, "MAGNETIC SUCTION BUILDING BLOCK," issued September 26, 2023 (Compl. ¶22).

The Invention Explained

  • Problem Addressed: The patent's background section describes a limitation in existing magnetic building blocks, which typically have "single stacking angles" that only allow blocks to be connected along the same axis (ʼ622 Patent, col. 1:19-22). This limitation restricts the types of structures that can be built and reduces the toy's creative potential (ʼ622 Patent, col. 1:22-28).
  • The Patented Solution: The invention is a magnetic block with an internal structure that places rotatable magnets within compartments at the "crossed corners" where the block's side walls meet (ʼ622 Patent, col. 1:47-51). This configuration, supported by an internal "installation bracket," allows the magnets to freely orient their north and south poles to attract magnets in other blocks, enabling stable connections at various angles, described as "misplaced modeling" (ʼ622 Patent, col. 5:4-16; Fig. 9).
  • Technical Importance: This design purports to greatly enrich the building modes and playing methods compared to on-axis stacking, thereby increasing a child's interest in building more complex and creative models (ʼ622 Patent, col. 1:39-44).

Key Claims at a Glance

  • The complaint asserts independent Claim 1 and dependent Claim 4 (Compl. ¶31).
  • The essential elements of independent Claim 1 include:
    • A square building block main body with six side walls.
    • Four "internal wall groups" that form four "compartments" at the block's joints.
    • An "installation bracket" comprising a central "connecting shaft," four "stop columns," and four "connection portions."
    • The stop columns and side walls define eight "compartment units."
    • Eight rotatable "magnet units," one in each compartment unit, each with a north and south pole.

U.S. Patent No. 12,151,182 - MAGNETIC SUCTION BUILDING BLOCK

  • Patent Identification: U.S. Patent No. 12,151,182, "MAGNETIC SUCTION BUILDING BLOCK," issued November 26, 2024 (Compl. ¶23).

The Invention Explained

  • Problem Addressed: As a continuation-in-part, the '182 Patent addresses the same problem as its parent: the "single stacking angles" of conventional magnetic blocks that limit creative play ('182 Patent, col. 1:22-29).
  • The Patented Solution: The '182 Patent claims a similar block structure but describes the internal mechanism differently. Instead of an "installation bracket," Claim 1 recites four "supporting poles" located within the corner compartments ('182 Patent, Claim 1). Each supporting pole holds two magnet units, one at each of its "opposite ends," which are capable of rotating within the compartment to facilitate magnetic attraction with other blocks ('182 Patent, Claim 1).
  • Technical Importance: The stated goal remains the same: to "implement the design and building of the misplaced shapes" and enrich the playing method beyond simple on-axis stacking ('182 Patent, col. 7:23-25).

Key Claims at a Glance

  • The complaint asserts independent Claim 1 and dependent Claim 7 (Compl. ¶43).
  • The essential elements of independent Claim 1 include:
    • A square building block main body with six side walls.
    • Four "internal wall groups" that define four "compartments."
    • Four "supporting poles," each located within one of the compartments.
    • Four groups of magnet units, with each group comprising two magnet units located at "two opposite ends of a corresponding support pole."
    • Each magnet unit is capable of rotating and has a north and south pole.

III. The Accused Instrumentality

Product Identification

The accused instrumentalities are "magnetic building block" toys sold by Defendant under the name "DOLLARSIGN LIMITED" through an Amazon storefront (Compl. ¶6, ¶16). The complaint identifies a number of specific Amazon Standard Identification Numbers (ASINs) for the accused products (Compl. ¶16).

Functionality and Market Context

The complaint alleges that the accused products are "unauthorized imitations" that incorporate the patented inventions (Compl. ¶6, ¶10). The functionality is described as a "blatant copying of the patented structures," specifically targeting the "distinctive internal configuration and magnetic assembly methods" claimed in the Asserted Patents (Compl. ¶8). The complaint alleges these products are sold and offered for sale to consumers throughout the United States, including in the Eastern District of Texas (Compl. ¶7, ¶15). No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

The complaint references claim charts for both the ’622 Patent (Exhibit 6) and the ’182 Patent (Exhibit 7) but does not include these exhibits in the filing (Compl. ¶31, ¶43). In their absence, the infringement theory is based on the narrative allegations in the complaint.

Plaintiff alleges that Defendant directly infringes the Asserted Patents, either literally or under the doctrine of equivalents, by making, using, selling, offering to sell, and/or importing the accused magnetic building blocks (Compl. ¶26, ¶38). The core of the infringement allegation is that the accused products replicate the unique internal structures claimed in the patents, which enable multi-axis, "misplaced" connections between blocks (Compl. ¶8). Without the claim charts, the specific mapping of accused product components to claim limitations is not detailed in the complaint.

V. Key Claim Terms for Construction

  • For the ’622 Patent:

    • The Term: "installation bracket" (Claim 1)
    • Context and Importance: This term defines the entire internal assembly that positions the rotatable magnets. The infringement analysis will depend on whether the accused products contain a structure that meets the definition of an "installation bracket," which the claim further defines as comprising a "connecting shaft," "stop columns," and "connection portions." Practitioners may focus on whether this term is limited to the specific embodiment shown in the patent's figures or if it can be construed more broadly to cover other internal magnet-holding structures.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: The specification states the function of the bracket is to "stop the magnet," which could support construing the term to cover any structure that performs this function (ʼ622 Patent, col. 2:60-62).
      • Evidence for a Narrower Interpretation: The detailed description and Figure 2 illustrate a very specific structure for the installation bracket (7), including a central connecting shaft (71) and four radiating stop columns (711-714) (ʼ622 Patent, col. 8:50-57). A defendant may argue the claim is limited to this disclosed configuration.

  • For the ’182 Patent:

    • The Term: "supporting pole" (Claim 1)
    • Context and Importance: This term is central to Claim 1 of the ’182 Patent, as it describes the element within each compartment that holds the magnet units at its "opposite ends." The outcome of the infringement analysis for this patent may hinge on what structures qualify as a "supporting pole." Notably, the term "supporting pole" does not appear in the patent's written description, which is substantially similar to that of the parent '622 patent.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: A party may argue the term should be given its plain and ordinary meaning—any rod-like structure that supports the magnets as claimed. The claim itself provides context, requiring it to be in a compartment and hold two magnet units at opposite ends.
      • Evidence for a Narrower Interpretation: The absence of the term "supporting pole" from the specification raises the question of whether the specification provides adequate written description for this claim element. A defendant may argue that this lack of explicit support renders the term indefinite or requires it to be narrowly construed by reference to the structures that are disclosed, such as the "stop columns" from the parent patent.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges that Defendant actively induces infringement by "manufacturers, shippers, distributors, and retailers" and contributes to infringement by selling and offering to sell the products in the United States (Compl. ¶28-29, ¶40-41). The factual basis alleged for inducement is that Defendant "intentionally causes, urges, or encourages" these third parties to infringe (Compl. ¶32, ¶44).
  • Willful Infringement: Willfulness is alleged based on Defendant’s purported knowledge of the Asserted Patents. The complaint specifically alleges that Defendant knew of or was willfully blind to the patents "since at least October 18, 2024, as CHEN marked the patent number on the product's manual" (Compl. ¶32, ¶44). This allegation points to pre-suit knowledge based on constructive notice via patent marking.

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

  • Claim Construction and Written Description: A primary legal battle will likely concern claim construction, particularly for the key structural terms "installation bracket" ('622 Patent) and "supporting pole" ('182 Patent). The complete absence of the term "supporting pole" from the '182 patent's specification may create a significant dispute over claim definiteness and written description, raising the question of whether the claim is adequately supported by the disclosure.
  • Evidentiary Proof of Infringement: The complaint relies on conclusory allegations of "blatant copying" of internal structures. A key evidentiary question will be whether Plaintiff can produce technical evidence—such as teardowns, imaging of the accused products, or expert analysis—to prove that the unseen internal mechanisms of Defendant’s products practice the specific, multi-part limitations of the asserted claims.
  • Jurisdiction and Enforceability: The complaint asserts that Defendant is a foreign entity that has "deliberately concealed its identity" and provided a false business address (Compl. ¶9, ¶17). This raises a practical question of procedure and enforcement: will Plaintiff be able to successfully establish personal jurisdiction, effect service, and ultimately enforce any judgment against a foreign entity whose identity and location are allegedly obscured?