Dongguan Best Travel Electronics Co Ltd v. Partnerships Unincorp Associations

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Dongguan Best Travel Electronics Co., Ltd. (China)
  • Defendant: The Partnerships and Unincorporated Associations Identified on Schedule A (Unspecified; alleged to operate from the People's Republic of China or other foreign jurisdictions)
  • Plaintiff’s Counsel: Avek IP, LLC
• Case Identification: 5:26-cv-00563, W.D. Tex., 01/30/2026
• Venue Allegations: Venue is based on allegations that Defendants operate interactive e-commerce stores that directly target and sell products to consumers in the Western District of Texas.
• Core Dispute: Plaintiff alleges that Defendants’ power converter products infringe a patent related to an overload prevention device for multi-country power converters.
• Technical Context: The technology concerns universal travel power adapters, which allow electronic devices to be used in countries with different electrical outlet standards, and incorporates a safety fuse to prevent circuit overloads.
• Key Procedural History: The complaint alleges that the patent-in-suit was assigned to the Plaintiff on January 9, 2026, establishing Plaintiff's standing to bring this action.

Case Timeline

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

U.S. Patent No. 12,199,387 - Overload prevention device for multi-country power converter

The Invention Explained

• Problem Addressed: The patent describes safety issues with conventional multi-country power converters, noting that exposed or easily removable fuses can create risks of electrical leakage and shock, particularly if mishandled by children. It also notes that such designs can occupy significant space, which is contrary to the goal of product miniaturization. ’387 Patent, col. 1:39-58
• The Patented Solution: The invention is an overload prevention device featuring a fuse tube housed within a detachable fuse holder. This holder is mounted within the converter’s main body and electrically connects the input pins (e.g., for US or UK standards) to the output socket via upper and lower conductive pieces that clamp onto the fuse. This integrated design aims to create a safer, more stable, and compact electrical path that protects the circuit from overloads while preventing incorrect user handling. ’387 Patent, Abstract; col. 2:1-38
• Technical Importance: The described approach sought to enhance the safety and packaging efficiency of universal travel adapters by securing the fuse within the device's internal structure. ’387 Patent, col. 1:59-66

Key Claims at a Glance

• The complaint asserts independent claim 1. Compl. ¶30
• The essential elements of independent claim 1 include:
  • An upper and lower cover forming a main body, a US-standard pin assembly, and a UK-standard pin assembly.
  • A fuse holder detachably mounted in the lower cover, with a fuse tube mounted in a mounting frame within the holder.
  • A lower conductive piece that clamps the lower part of the fuse tube and connects to the pin assemblies.
  • An upper conductive piece that clamps the upper part of the fuse tube and connects to the device’s socket hole.
  • A specific mechanical interface including a "mounting cover" and "mounting limit part" on the fuse holder, which mates with a "fuse tube insertion hole" and a "pulling-out avoidance groove" on the main body's lower cover.
• The complaint does not explicitly reserve the right to assert dependent claims.

III. The Accused Instrumentality

Product Identification

The complaint accuses "power converter products" (the "Infringing Products") sold by numerous e-commerce stores operated by the Defendants. Compl. ¶¶ 3-4

Functionality and Market Context

• The complaint alleges that Defendants make, use, offer for sale, sell, and/or import power converters that incorporate Plaintiff's patented technology. Compl. ¶3
• Plaintiff alleges it purchased and analyzed samples of the Infringing Products and found them to be "identical in all material aspects" and that they are "the same in all respects relevant to the '387 Patent." Compl. ¶8
• The complaint includes a representative figure from the '387 Patent, showing a multi-country power converter with a visible fuse compartment, to illustrate the type of product at issue. Compl. ¶12, p. 5
• The complaint asserts that Defendants operate as a "swarm of foreign counterfeiters" using anonymity to sell the Infringing Products to unknowing consumers via the internet. Compl. ¶8

IV. Analysis of Infringement Allegations

The complaint references a claim chart in "Schedule A-1" that allegedly maps the elements of the claims of the '387 Patent to the Infringing Products. Compl. ¶8 As this exhibit was not provided with the complaint, the infringement theory is summarized below in prose.

The complaint alleges that the Defendants have directly infringed, and continue to infringe, at least Claim 1 of the '387 Patent by making, using, selling, or importing the Infringing Products in the United States. Compl. ¶30 The core of the infringement allegation rests on the assertion that Plaintiff purchased and analyzed the accused products and determined they were "identical in all material aspects." Compl. ¶8 The verification by Plaintiff’s CEO further states that the analysis depicted in the (missing) Schedule A-1 is accurate. Verification ¶3 The narrative theory is therefore one of literal infringement, where the accused power converters are alleged to be direct copies that practice every structural and functional limitation of Claim 1 of the ’387 Patent.

• Identified Points of Contention:
  • Evidentiary Question: A central question will be whether discovery can substantiate the conclusory allegation that the products sold by each distinct Defendant are, in fact, "identical" and practice every limitation of Claim 1. The infringement case hinges entirely on evidence that is referenced but not provided in the complaint.
  • Technical Question: Assuming the products are structurally similar to the patent's embodiments, a point of contention may arise regarding whether the accused devices meet the highly specific mechanical limitations of Claim 1. For instance, does the accused fuse holder possess a "mounting cover" with a "mounting limit part" and a "pull-out guide surface" that interacts with a corresponding "fuse tube insertion hole" and "pulling-out avoidance groove" on the main body, as explicitly required by the claim language?

V. Key Claim Terms for Construction

• The Term: "fuse holder detachably mounted in the lower cover"

• Context and Importance: This term defines the physical relationship between the fuse assembly and the main body of the converter. The "detachable" nature is critical to the invention's claimed safety and usability features. Practitioners may focus on this term because its construction will determine whether a product with a hinged fuse door, as opposed to a fully removable cartridge, falls within the scope of the claim.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The specification describes the process of "pull[ing] out the fuse tube 6 and the fuse holder 5 from the power converter," which may support an interpretation that "detachable" means fully separable from the main body. ’387 Patent, col. 7:19-22
  • Evidence for a Narrower Interpretation: The figures and claims detail a specific sliding mechanism where the holder is "mounted in the lower cover" and features a "mounting cover" and "mounting limit part," suggesting a specific type of detachable engagement rather than any form of non-permanent attachment. ’387 Patent, col. 11:7-16; Fig. 6

• The Term: "lower conductive piece"

• Context and Importance: This term, along with the "upper conductive piece," defines the complete electrical circuit through the fuse. Infringement requires the accused products to contain components that map to these claimed "pieces," including their recited clamping and connection functions. Practitioners may focus on this term because its scope will determine if the claim is limited to the specific "integrally formed type structure" shown or if it can read on a wider range of conductive assemblies.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The term itself is functionally broad and could be argued to encompass any single or multi-part conductive element that connects the pin assemblies to the fuse.
  • Evidence for a Narrower Interpretation: The specification describes the "lower conductive piece 7" as an "integrally formed type structure" and details its specific parts, including a "connection piece 72," a "US-standard clamping part 73," and a "UK-standard clamping part 74." This may support an argument that the term is limited to a single, unitary component with these specific features. ’387 Patent, col. 6:18-32

VI. Other Allegations

• Indirect Infringement: The complaint makes a passing reference to indirect infringement Compl. ¶29, but Count I is for direct infringement under 35 U.S.C. § 271(a). The complaint does not plead specific facts to support the knowledge and intent elements required for claims of induced or contributory infringement.
• Willful Infringement: The complaint alleges that Defendants' infringement "is and has been willful," based on the allegation that they have acted "knowingly and willfully." Compl. ¶¶ 24-25, 29 The complaint does not provide a factual basis for this knowledge, such as pre-suit notice or a finding of copying beyond the allegation that the products are identical.

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

• Procedural Viability and Joinder: A threshold issue for the court will be procedural: can Plaintiff properly join numerous, separately operated, and anonymous e-commerce entities as a "swarm" of defendants in a single action under 35 U.S.C. § 299? The case may depend on Plaintiff’s ability to prove that the accused products are "the same" and that the infringement arises from a "series of transactions or occurrences," as the complaint argues is established by the Defendants' allegedly coordinated activities.
• Evidentiary Sufficiency: A core substantive question will be one of evidence: can Plaintiff prove, on a defendant-by-defendant basis, that the accused power converters meet every specific structural limitation of Claim 1? Given the claim’s detailed recitation of mechanical features like the "pulling-out avoidance groove" and "pull-out guide surface," the case will likely turn on a rigorous, element-by-element comparison for which the complaint currently provides only conclusory allegations.