DCT
1:23-cv-09529
Voltstar Tech Inc v. SM Tek Group Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Voltstar Technologies, Inc. (Illinois)
- Defendant: SM Tek Group Inc. (New York)
- Plaintiff’s Counsel: Sriplaw PLLC
- Case Identification: 1:23-cv-09529, E.D.N.Y., 12/28/2023
- Venue Allegations: Venue is alleged based on Defendant’s commission of infringing acts and its regular and established place of business within the district.
- Core Dispute: Plaintiff alleges that Defendant’s Bluestone USB Wall Charger infringes a reissue patent related to the dimensional and functional characteristics of compact electrical charger plugs.
- Technical Context: The technology concerns the design and packaging of AC-to-DC power adapters, commonly used for charging portable electronic devices, where compact size and non-interference with adjacent wall outlets are key market features.
- Key Procedural History: The patent-in-suit, U.S. Patent No. RE48,794, is a reissue of U.S. Patent No. 9,024,581. The complaint notes that the reissue amended Claim 1 to add a specific width limitation ("less than 1.75 inches") and to narrow a length limitation from "equal to or less than 2.0 inches" to strictly "less than 2.0 inches," a change that will likely be central to the infringement and damages analyses.
Case Timeline
| Date | Event |
|---|---|
| 2008-05-21 | Earliest Priority Date ('581 Patent) |
| 2015-05-05 | Issue Date of U.S. Patent No. 9,024,581 (Original Patent) |
| 2021-10-26 | Issue Date of U.S. Patent No. RE48,794 E (Reissue Patent) |
| 2023-12-28 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Reissue Patent No. RE48,794 E - "Charger Plug with Improved Package," issued October 26, 2021
The Invention Explained
- Problem Addressed: The patent describes issues with prior art charger plugs, such as their bulkiness, which often causes them to block adjacent wall outlets. (RE48,794 E Patent, col. 1:41-48). It also identifies the manufacturing complexity and cost associated with "insert molding" electrical blades into the plastic housing and the space required for internal soldering. (RE48,794 E Patent, col. 2:1-31).
- The Patented Solution: The invention claims to solve these problems through a specific charger design that features a compact housing with defined dimensional limits and a construction that avoids interference with adjacent outlets. (RE48,794 E Patent, Abstract; col. 14:46-59). The design facilitates easier assembly by, in some embodiments, using slidably mounted blades and spring contacts instead of solder, which reduces the overall package size. (RE48,794 E Patent, col. 4:11-17, Fig. 3).
- Technical Importance: The technical approach addresses a persistent consumer issue and manufacturing challenge in the market for portable electronics accessories: creating smaller, more convenient chargers without compromising functionality or driving up production costs. (RE48,794 E Patent, col. 1:12-18).
Key Claims at a Glance
- The complaint asserts infringement of at least independent Claim 1. (Compl. ¶26).
- Independent Claim 1 Essential Elements:
- A charger plug for connecting to a power source to convert 120V input to DC output for a rechargeable device.
- A housing containing the plug.
- First and second separate blade members with prong portions extending from a front wall of the housing.
- A DC connector with an aperture to receive a power cord plug.
- The housing has a face area, an outer profile, and a rear end.
- The plug is configured for a standard wall outlet.
- The housing is sized with a longitudinal length less than 2.0 inches and a width of the housing outer profile being less than 1.75 inches.
- The outer profile has no interference with an adjacent receptacle of the power source.
- The complaint does not explicitly reserve the right to assert dependent claims.
III. The Accused Instrumentality
Product Identification
- The "Bluestone USB Wall Charger." (Compl. ¶17).
Functionality and Market Context
- The accused product is a charger that connects an AC wall outlet to a device, such as a mobile phone, to provide DC power for recharging a battery. (Compl. ¶18).
- The complaint alleges the Bluestone Wall Charger employs a "reduced plug-size charger plug" designed so that it "does not block or interfere with the use of adjacent outlets." (Compl. ¶19). A photograph of the accused product shows a small, white, rectangular charger with two AC prongs. (Compl. ¶17). The complaint also alleges the charger’s size and shape allow for easy insertion and removal of a power cord while the charger remains plugged into an outlet. (Compl. ¶20).
IV. Analysis of Infringement Allegations
The complaint references a claim chart exhibit that is not provided. The following table summarizes the infringement theory based on the narrative allegations in the complaint.
RE48,794 E Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a charger plug...to convert 120V input power received from the power source to DC output power | The Bluestone Wall Charger is described as a charger connecting an AC power source (wall outlet) to a device to provide DC power. (Compl. ¶18). | ¶18 | col. 14:20-24 |
| being sized so that the charger plug housing comprises a longitudinal length extending between the front wall and the rear end and the longitudinal length is less than 2.0 inches, a width of the housing outer profile being less than 1.75 inches... | The complaint alleges the Bluestone Wall Charger has a longitudinal length of "approximately 1.672 inches" and a width of "approximately 1.629 inches." (Compl. ¶23). A visual is provided of the accused product. (Compl. ¶17). | ¶23 | col. 14:46-52 |
| the outer profile having no interference with an adjacent receptacle of the power source... | The complaint alleges that the Bluestone Wall Charger "does not block or interfere with the use of adjacent outlets." (Compl. ¶19). | ¶19 | col. 14:53-55 |
Identified Points of Contention
- Scope Questions: A central question will be whether the specific dimensional measurements of the accused product ("approximately 1.672 inches" and "approximately 1.629 inches") are definitively proven and fall within the claim scope of "less than 2.0 inches" and "less than 1.75 inches," respectively. The use of "approximately" in the complaint suggests that precise measurement may become a point of factual dispute.
- Technical Questions: The claim requires the "outer profile" to have "no interference" with an adjacent receptacle. The parties may dispute what constitutes "interference" and how the specific shape and dimensions of the accused product's "outer profile" meet this functional limitation across all standard receptacle configurations. The complaint does not provide evidence beyond a conclusory statement and a single photograph to support this functional claim.
V. Key Claim Terms for Construction
- The Term: "a width of the housing outer profile being less than 1.75 inches"
- Context and Importance: This limitation was added during reissue, narrowing the original claim and forming a core basis of the infringement allegation. Practitioners may focus on this term because its precise measurement methodology is not defined in the claim, which could lead to disputes over how and where on the "outer profile" the "width" should be measured, especially on a product with curved or tapered sides. (Compl. ¶12).
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The claim language itself does not specify a measurement protocol, which could support an argument that any reasonable measurement of the product's maximum width should suffice. The specification generally discusses reducing "vertical and lateral dimensions" without defining a precise measurement axis. (RE48,794 E Patent, col. 1:42-44).
- Evidence for a Narrower Interpretation: The patent figures, such as Fig. 1 and Fig. 15, depict a specific housing shape. A defendant may argue that the term "width" should be interpreted in the context of the specific orientation and geometry shown in these embodiments, potentially excluding certain measurement points on an differently shaped accused product. The specification also gives an exemplary width of "approximately 1.35 inches," which could be used to argue the claim is directed to a specific range far below the 1.75-inch limit. (RE48,794 E Patent, col. 14:5-6).
VI. Other Allegations
The complaint does not contain sufficient detail for analysis of indirect infringement or willful infringement. While the prayer for relief requests a finding of willfulness, the factual allegations in the body of the complaint do not specify a basis for this claim, such as pre- or post-suit knowledge. (Compl. ¶C, p. 7).
VII. Analyst’s Conclusion: Key Questions for the Case
- A central issue will be one of claim scope and measurement: Given that the key dimensional limitations were added during reissue, the case may turn on how the court construes the term "width of the housing outer profile" and what evidence is required to prove that the accused product, with its specific geometry, meets the "less than 1.75 inches" limitation.
- A key evidentiary question will be one of functional performance: Can the plaintiff provide sufficient factual evidence, beyond conclusory allegations, to demonstrate that the accused charger’s "outer profile" causes "no interference" with adjacent receptacles in all standard configurations, as required by the plain language of Claim 1?
- A significant legal question will concern the impact of the reissue: Because the asserted claim was narrowed during reissue, the court will need to address whether Defendant's alleged infringement began only after the reissue date, or if the claims are "substantially identical" to the original patent's claims, which would allow for the recovery of damages for past infringement and potentially limit a defense of intervening rights. (Compl. ¶13).