Voltstar Tech Inc v. Shenzhen Huafengda Plastic Products Co Ltd

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Voltstar Technologies, Inc. (Illinois)
  • Defendant: Shenzhen Huafengda Plastic Products Co. Ltd., A/K/A Luoatip (China)
  • Plaintiff’s Counsel: SRIPLAW
• Case Identification: 1:25-cv-23421, S.D. Fla., 07/30/2025
• Venue Allegations: Venue is alleged to be proper because the defendant is not a resident of the United States and has committed acts of infringement within the district.
• Core Dispute: Plaintiff alleges that Defendant’s USB wall chargers infringe a reissue patent related to the dimensional and non-interference characteristics of compact charger plugs.
• Technical Context: The technology concerns the design of small AC-to-DC power adapters, commonly used for consumer electronics, that are compact enough not to obstruct adjacent electrical outlets.
• Key Procedural History: The patent-in-suit, RE48794, is a reissue of U.S. Patent No. 9,024,581. The complaint notes that the reissue process amended original Claim 1 by adding a specific width limitation and removing language that allowed the length to be "equal to" 2.0 inches, thereby narrowing the claim's dimensional scope. The complaint also asserts that Plaintiff has previously licensed the patent to third parties.

Case Timeline

Date	Event
2008-05-21	Priority Date for U.S. Patent No. 9,024,581
2015-05-05	U.S. Patent No. 9,024,581 Issues
2021-10-26	U.S. Reissue Patent No. RE48,794 E Issues
2025-07-30	Complaint Filed

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

U.S. Reissue Patent No. RE48,794 E - "Charger Plug With Improved Package"

The Invention Explained

• Problem Addressed: The patent's background describes issues with prior art charger plugs, which were often bulky. This bulk could cause a plug to interfere with the use of adjacent receptacles on a wall outlet or power strip. Furthermore, plugs that protruded excessively from the wall were inconvenient and susceptible to being struck or dislodged. (’794 Patent, col. 1:42-59). The patent also notes that common manufacturing processes, such as insert-molding electrical blades and hand-soldering them to internal circuit boards, were costly, time-consuming, and required extra space within the housing. (’794 Patent, col. 2:11-41).
• The Patented Solution: The invention claims to solve these problems through a charger with a specifically dimensioned housing and a simplified internal construction. The design features separate, slidably mounted blades that connect to the internal circuitry via spring contacts, which can obviate the need for soldering and reduce the overall package size. (’794 Patent, Abstract; col. 4:29-43). The external dimensions are claimed to be sufficiently small in both length and width to prevent the charger from blocking adjacent outlets. (’794 Patent, col. 13:42-48).
• Technical Importance: This design approach sought to reduce manufacturing costs and complexity while creating smaller, more convenient, and aesthetically pleasing chargers for the growing market of portable electronic devices. (’794 Patent, col. 2:42-50).

Key Claims at a Glance

• The complaint asserts independent Claim 1. (Compl. ¶29).
• The essential elements of Claim 1 include:
  • A charger plug for converting 120V input power to DC output power.
  • A housing containing separate blade members with prong portions to connect to a power source and a DC connector to connect to a device via a power cord.
  • The housing has a specific size, comprising a longitudinal length of less than 2.0 inches and a width of the housing's "outer profile" of less than 1.75 inches.
  • The housing's "outer profile" has "no interference with an adjacent receptacle" when a similar charger is plugged into other available orientations.
• The complaint does not explicitly reserve the right to assert dependent claims.

III. The Accused Instrumentality

Product Identification

The accused products are a series of "LUOATIP" branded chargers sold on Amazon.com, including the "USB Wall Charger, LUOATIP 3-Pack 2.1A 5V Dual Port Cube Power Adapter" and several "USB C Charger Block" products. (Compl. ¶21, pp. 5-6).

Functionality and Market Context

The complaint describes the accused products as chargers that connect between an AC power source (e.g., a wall outlet) and a DC-powered device (e.g., a mobile phone) to provide charging power. (Compl. ¶22). It alleges the products feature a "reduced plug-size" design intended to prevent the blocking of adjacent outlets, a key feature highlighted in the patent-in-suit. (Compl. ¶23).

IV. Analysis of Infringement Allegations

The complaint references a claim chart in its Exhibit 3, which was not publicly filed with the initial complaint. The narrative infringement theory presented in the complaint is summarized below.

The complaint alleges that the accused LUOATIP chargers directly infringe at least Claim 1 of the ’794 Patent. The core of the infringement theory rests on the external form factor and functionality of the accused products. The complaint asserts that the chargers are used to connect an AC power source to a rechargeable device, satisfying the preamble of the claim. (Compl. ¶22). It further alleges that the "reduced plug-size" and shape of the accused chargers ensure they "do not block or interfere with the use of adjacent outlets," which maps directly to the functional limitation in element 1(ii) of the asserted claim. (Compl. ¶23). The complaint also alleges the chargers are sized and shaped for convenient use, allowing a power cord to be inserted and removed without unplugging the charger from the wall. (Compl. ¶24).

No probative visual evidence provided in complaint.

• Identified Points of Contention:
  • Evidentiary Questions: A primary question will be whether Plaintiff can produce evidence that the accused products meet the precise dimensional limitations of Claim 1(i): a longitudinal length "less than 2.0 inches" and a "width of the housing outer profile being less than 1.75 inches." The complaint makes qualitative allegations about the products' "reduced plug-size" but provides no quantitative measurements to substantiate infringement of these specific claim elements.
  • Scope Questions: The infringement analysis for element 1(ii) will depend on the definition of "no interference with an adjacent receptacle." This raises the question of what constitutes "interference" (e.g., any physical overlap versus functional obstruction) and what type of "adjacent receptacle" and competing plug are used as the standard for comparison.

V. Key Claim Terms for Construction

• The Term: "outer profile"

• Context and Importance: This term appears in both dimensional and functional limitations of Claim 1. Its definition is critical for determining what part of the housing is measured to meet the "less than 1.75 inches" width requirement and what physical boundary must avoid "interference with an adjacent receptacle." Practitioners may focus on this term because its construction will define the precise geometric shape against which infringement is measured.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: A party could argue for the plain and ordinary meaning, suggesting the "outer profile" encompasses the maximum physical extents of the housing in any given plane, including any protrusions.
  • Evidence for a Narrower Interpretation: Claim 1 itself describes the "outer profile" as being "defined by a perimeter of the front wall and defined by a plug body extending rearward." (’794 Patent, col. 14:37-40). A party could argue this language limits the profile to the shape extruded directly from the front face, potentially excluding features like tapered rear sections or flanges from the measurement.

• The Term: "no interference with an adjacent receptacle"

• Context and Importance: This functional limitation is central to the patent's stated purpose. Its construction will determine the performance standard for infringement. The key dispute will likely be the rigor of the "no interference" standard and the conditions under which it is tested.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The patent’s background explicitly identifies the problem of a plug providing "little or no interference with use of an adjacent receptacle" as a key challenge. (’794 Patent, col. 1:45-48). This could support an interpretation that requires a complete lack of physical or functional obstruction of a standard adjacent outlet.
  • Evidence for a Narrower Interpretation: The claim language qualifies this limitation by stating it applies "when a like charger plug is mounted in all available orientations in any of the other receptacles." (’794 Patent, col. 14:50-54). A party could argue the test for interference is limited to scenarios involving another identical charger, not necessarily any possible plug that could be used in the adjacent socket.

VI. Other Allegations

• Willful Infringement: The complaint alleges that Defendant had "actual or constructive knowledge of Plaintiff's intellectual property rights" and asks the court to find the infringement was "willful, wanton, and deliberate," seeking a corresponding enhancement of damages. (Compl. ¶20; Prayer for Relief ¶C).

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

1. A central issue will be one of factual proof: Can the Plaintiff provide admissible evidence, such as expert measurements, demonstrating that the accused LUOATIP chargers satisfy the specific numerical limitations of Claim 1 (length < 2.0", width < 1.75")? The complaint currently lacks this quantitative detail.
2. The case will likely involve a significant dispute over claim construction: How will the court define the "outer profile" of the housing for measurement, and what is the scope of the functional requirement for "no interference with an adjacent receptacle"? The resolution of these terms will set the boundaries for the infringement analysis.
3. A key legal question will concern the impact of the patent's reissue history: The court will have to consider how the narrowing amendments made during reissue—specifically the addition of the width limitation to Claim 1—affect claim construction and whether they give rise to intervening rights that could shield the Defendant from damages for some of its accused sales.