DCT
1:25-cv-23181
Voltstar Tech Inc v. Shenzhen Bai Ying Hui Technology Co Ltd
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Voltstar Technologies, Inc. (Illinois)
- Defendant: Shenzhen Bai Ying Hui Technology Co., Ltd. a/k/a Ailkin Direct (China)
- Plaintiff’s Counsel: Sriplaw, PLLC.
- Case Identification: 1:25-cv-23181, S.D. Fla., 07/16/2025
- Venue Allegations: Venue is alleged to be proper because the defendant is not a resident of the United States and may therefore be sued in any judicial district, and because the defendant has allegedly committed acts of infringement within the district.
- Core Dispute: Plaintiff alleges that Defendant’s line of USB wall chargers infringes a reissue patent related to the specific dimensional and functional characteristics of compact power adapters.
- Technical Context: The technology concerns AC-to-DC power adapters, ubiquitous for charging consumer electronics, with a focus on designs that are compact enough to avoid obstructing adjacent wall outlets.
- Key Procedural History: The patent-in-suit, U.S. Reissue Patent No. RE48,794 E, is a reissue of U.S. Patent No. 9,024,581. The complaint states the reissue narrowed a dimensional limitation in Claim 1, changing the required length from "equal to or less than 2.0 inches" to strictly "less than 2.0 inches" and adding a width limitation of "less than 1.75 inches." This narrowing of the claim scope may introduce questions regarding the doctrine of intervening rights. The complaint also notes that Plaintiff has entered into licensing agreements with third parties for its patent.
Case Timeline
| Date | Event |
|---|---|
| 2008-05-21 | '581 Patent Priority Date |
| 2015-05-05 | Original '581 Patent Issued |
| 2021-10-26 | '794 Reissue Patent Issued |
| 2025-07-16 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Reissue Patent No. RE48,794 E - "Charger Plug With Improved Package"
- Patent Identification: U.S. Reissue Patent No. RE48,794 E ("Charger Plug With Improved Package"), issued October 26, 2021.
The Invention Explained
- Problem Addressed: The patent's background section describes problems with prior art power adapters, which were often bulky and could block the use of adjacent electrical outlets (RE48,794 E Patent, col. 1:42-47). Further, manufacturing processes involving insert-molding electrical blades into plastic housings and manually soldering connections were described as costly, time-consuming, and prone to error (RE48,794 E Patent, col. 1:61-2:24).
- The Patented Solution: The invention claims a "reduced plug-size charger plug" designed to be compact and unobtrusive ('794 Patent, Abstract). The patented solution specifies precise dimensional limitations for the charger's housing to ensure it does not interfere with adjacent outlets ('794 Patent, col. 13:46-58). It also discloses alternative assembly methods, such as using slidably mounted blades and spring contacts, to obviate the need for insert molding and soldering, thereby simplifying manufacturing ('794 Patent, col. 4:13-26).
- Technical Importance: The invention addresses a clear market need for smaller, more convenient, and less expensive power adapters driven by the proliferation of portable electronic devices ('794 Patent, col. 1:21-28).
Key Claims at a Glance
- The complaint asserts infringement of at least Claim 1 of the '794 Patent (Compl. ¶29).
- Independent Claim 1 of the '794 Patent recites the following essential elements for a charger plug:
- A housing with first and second separate blade members secured within it.
- A DC connector for a removable power cord.
- A specific configuration where the charger housing has an outer profile and is sized with a longitudinal length less than 2.0 inches and a width less than 1.75 inches.
- A functional requirement that the outer profile has no interference with an adjacent receptacle of a power source when a similar charger is mounted in other available orientations.
- The complaint does not explicitly reserve the right to assert dependent claims, but infringement is alleged for "at least one of the claims" (Compl. ¶26).
III. The Accused Instrumentality
Product Identification
- The accused products are a line of "AILKIN" branded USB wall chargers sold on Amazon.com, identified in the complaint by several ASINs, such as B0734SN6VR and B07MH25GWV (Compl. ¶21).
Functionality and Market Context
- The accused products are AC-to-DC power adapters designed to be plugged into a standard wall outlet to supply charging power to electronic devices via USB ports (Compl. ¶22). The complaint alleges these chargers "employ a reduced plug-size" such that they do not block or interfere with adjacent outlets (Compl. ¶23). It further alleges that a power cord can be easily inserted and removed while the charger remains plugged into the wall (Compl. ¶24). No probative visual evidence provided in complaint.
IV. Analysis of Infringement Allegations
The complaint references a claim chart in an exhibit not provided with the filing. The following chart summarizes the infringement allegations for Claim 1 based on the narrative text of the complaint.
RE48,794 E Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A charger plug... comprising: first and second separate blade members secured within the housing... | The accused products are chargers that are plugged into a source of AC power, such as a wall outlet. | ¶22, 23 | col. 13:26-30 |
| the charger plug including a DC connector having an aperture adapted to removably receive a corresponding power cord plug end... | The complaint alleges a power cord can be easily inserted into and removed from the chargers. | ¶24 | col. 13:31-34 |
| i) being sized so that the charger plug housing comprises a longitudinal length... is less than 2.0 inches, a width of the housing outer profile being less than 1.75 inches... | The chargers allegedly "employ a reduced plug-size charger plug." The complaint does not provide specific measurements for the accused products. | ¶23 | col. 13:46-52 |
| ii) the outer profile having no interference with an adjacent receptacle of the power source... when a like charger plug is mounted in all available orientations... | The complaint alleges that "the chargers do not block or interfere with the use of adjacent outlets." | ¶23 | col. 13:53-58 |
- Identified Points of Contention:
- Factual Question: The complaint makes a conclusory allegation that the accused chargers have a "reduced plug-size" but offers no specific measurements to demonstrate they meet the explicit dimensional limitations of Claim 1(i) (length < 2.0 inches, width < 1.75 inches). A primary point of dispute will be whether discovery and expert analysis confirm that the accused products satisfy these precise numerical requirements.
- Scope Question: Claim 1(ii) requires "no interference with an adjacent receptacle... in all available orientations." The interpretation of this negative limitation will be critical. The court may need to determine whether "no interference" means an absolute lack of physical contact or the absence of any obstruction that would prevent the practical use of the adjacent outlet.
V. Key Claim Terms for Construction
The Term: "outer profile"
- Context and Importance: This term appears in both key limitations of Claim 1, defining the boundaries for the dimensional measurements (length and width) and the assessment of interference. Its construction will determine what physical features of the charger are included in the infringement analysis. Practitioners may focus on this term because its ambiguity could significantly expand or contract the scope of the claim.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification refers generally to the "plug body" and the "perimeter of the front wall," which could support an interpretation that includes the entire external surface of the charger housing ('794 Patent, col. 13:38-41).
- Evidence for a Narrower Interpretation: A defendant might argue that "outer profile" should be limited to the main body of the housing, as depicted in the patent's figures (e.g., FIG. 1, 10), and should exclude minor features like tapered edges or the cord connector area.
The Term: "no interference"
- Context and Importance: This functional term sets the performance standard for the non-obviousness feature of the invention. Whether the accused products infringe will depend heavily on whether their physical presence constitutes "interference."
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: Plaintiff may argue for a literal interpretation where any physical contact with the space required to use an adjacent outlet constitutes "interference," relying on the plain and absolute language of the claim.
- Evidence for a Narrower Interpretation: A defendant may argue that the term should be construed in light of the problem described in the patent's background, which is the hindrance of the "use of an adjacent receptacle" ('794 Patent, col. 1:45-47). This could support a narrower definition where "interference" only occurs if an adjacent outlet is rendered unusable for a standard plug.
VI. Other Allegations
- Indirect Infringement: The complaint does not include a count for indirect infringement and focuses its allegations on direct infringement under 35 U.S.C. § 271(a) (Compl. ¶28, Count I Heading).
- Willful Infringement: The complaint alleges on "information and belief" that the defendant had "actual or constructive knowledge" of the plaintiff's patent rights (Compl. ¶20). It requests a finding of willful infringement and treble damages in its prayer for relief (Compl. Prayer ¶C). The complaint does not, however, plead specific facts to support pre-suit knowledge of the patent.
VII. Analyst’s Conclusion: Key Questions for the Case
- A central evidentiary question will be one of factual compliance: does the evidence, once developed, show that the accused AILKIN chargers meet the precise numerical dimension requirements of Claim 1 (length less than 2.0 inches, width less than 1.75 inches)? The complaint's allegations on this point are currently unsubstantiated by specific facts.
- A core issue for claim construction will be the scope of functionality: how should the court define the term "no interference"? The resolution of whether this requires an absolute absence of physical contact or merely the preservation of practical use of an adjacent outlet will be determinative for infringement.
- A key procedural and damages question will arise from the reissue status of the patent: did the narrowing amendments made during reissue create intervening rights for the defendant under 35 U.S.C. § 252? The court may need to decide if the defendant's conduct prior to the reissue date (October 26, 2021) is shielded from damages, a dispute foreshadowed by the plaintiff's assertion that the reissued claims are "substantially identical" to the original.