DCT
2:24-cv-08737
Voltstar Tech Inc v. Belkin Intl Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Voltstar Technologies, Inc. (Illinois) v. Belkin International, Inc. (Delaware)
- Plaintiff’s Counsel: Sriplaw, PLLC.
- Case Identification: 2:24-cv-08737, C.D. Cal., 10/10/2024
- Venue Allegations: Venue is based on allegations that Defendant has committed acts of infringement and maintains a regular and established place of business within the Central District of California.
- Core Dispute: Plaintiff alleges that Defendant’s wall chargers and wireless charging pads infringe three patents related to compact charger design and energy-saving technology that reduces "phantom load" power consumption.
- Technical Context: The patents address two common issues in the consumer electronics charger market: the physical size of charger plugs and their tendency to block adjacent wall outlets, and the wasted energy consumed by chargers when not actively charging a device.
- Key Procedural History: The complaint identifies U.S. Patent No. RE48,794 as a reissue of U.S. Patent No. 9,024,581, noting a claim amendment to narrow the dimensional limitations of the charger housing. The complaint also notes that U.S. Patent No. 7,960,648 is a continuation of U.S. Patent No. 7,910,833. The patents-in-suit have a significant post-grant history not mentioned in the complaint; the '833 Patent has been subject to a disclaimer, an inter partes reexamination, and an inter partes review, resulting in the cancellation and amendment of numerous claims. The '648 Patent was also subject to an inter partes reexamination that cancelled and amended claims. This history will substantially impact the scope of the surviving asserted claims.
Case Timeline
| Date | Event |
|---|---|
| 2008-05-21 | Priority Date for '794 Patent (via original '581 Patent) |
| 2008-05-27 | Priority Date for '833 and '648 Patents |
| 2011-03-22 | U.S. Patent No. 7,910,833 Issues |
| 2011-06-14 | U.S. Patent No. 7,960,648 Issues |
| 2015-05-05 | U.S. Patent No. 9,024,581 (parent of '794) Issues |
| 2021-10-26 | U.S. Reissue Patent No. RE48,794 E Issues |
| 2024-10-10 | 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. (Compl. ¶7).
The Invention Explained
- Problem Addressed: The patent's background section describes problems with prior art charger plugs, including their physical size causing them to interfere with adjacent electrical outlets, their manufacturing complexity and cost associated with insert-molding and hand-soldering of components, and their inconvenient length. (Compl. ¶11; '794 Patent, col. 1:41-54, col. 2:11-24).
- The Patented Solution: The invention is a charger plug with specific, compact dimensional limitations designed to prevent interference with adjacent outlets. (Compl. ¶12). To achieve this compact size, the patent discloses a novel assembly method using slidable blades that connect to the internal printed circuit board (PCB) via solder-less spring contacts, which simplifies manufacturing and reduces the overall package size. ('794 Patent, Abstract; col. 3:13-24).
- Technical Importance: This design addresses the market demand for smaller, less obtrusive, and more convenient power adapters for the growing number of portable consumer electronic devices. (Compl. ¶11).
Key Claims at a Glance
- The complaint asserts infringement of at least Claim 1. (Compl. ¶40).
- Independent Claim 1 requires, in essence:
- A charger plug for converting 120V input to DC output, comprising a housing, blade members, and a DC connector.
- The housing has a specific size limitation: a longitudinal length less than 2.0 inches and a width less than 1.75 inches.
- The housing's outer profile must have "no interference with an adjacent receptacle of the power source" when plugged in.
- The configuration allows the power cord to be conveniently connected and disconnected while the charger remains plugged into the wall.
- The complaint does not explicitly reserve the right to assert dependent claims.
U.S. Patent No. 7,910,833 - "Energy-Saving Power Adapter/Charger"
- Patent Identification: U.S. Patent No. 7,910,833, "Energy-Saving Power Adapter/Charger," issued March 22, 2011. (Compl. ¶14).
The Invention Explained
- Problem Addressed: The patent targets "phantom load," which is the residual power consumed by power adapters when they are plugged into an outlet but the connected electronic device is either fully charged, turned off, or disconnected. (Compl. ¶17; '833 Patent, col. 2:1-4).
- The Patented Solution: The invention is a power device containing circuitry that automatically cuts power to the charger's main components when it detects that the electronic device is no longer drawing a significant load. ('833 Patent, Abstract). The patent describes using a "load sensing portion" that monitors pulses from the charger's transformer to determine the power draw and then switches the device to a "zero-energy" or "off" state. ('833 Patent, col. 9:15-39).
- Technical Importance: This technology aims to reduce widespread energy waste and lower electricity costs for consumers by eliminating a common source of inefficient power consumption. (Compl. ¶17; '833 Patent, col. 2:5-13).
Key Claims at a Glance
- The complaint asserts infringement of at least Claims 24, 33, and 36. Claim 24 is the independent claim. (Compl. ¶45).
- Independent Claim 24 (as amended during reexamination) requires, in essence:
- A power device with input/output portions and power conversion circuitry.
- Switching circuitry to activate the power circuitry to an "on" state.
- A "load sensing portion" that is operable to "sense one or more pulses" to determine the power load.
- Crucially, the load sensing portion determines the load by "measuring the frequency of the pulses."
- The complaint does not explicitly reserve the right to assert dependent claims but lists dependent claims 33 and 36.
U.S. Patent No. 7,960,648 - "Energy Saving Cable Assemblies"
- Patent Identification: U.S. Patent No. 7,960,648, "Energy Saving Cable Assemblies," issued June 14, 2011. (Compl. ¶18).
- Technology Synopsis: As a continuation of the '833 Patent, the '648 patent is also directed at reducing "phantom" load. (Compl. ¶21). It discloses a cable assembly with a switch, which may be located remotely from the main charger body (e.g., near the connector), that allows the user or an automatic circuit to disconnect the electrical device from power draw. ('648 Patent, Abstract).
- Asserted Claims: The complaint asserts infringement of at least Claims 31, 32, and 39. Claim 31 is independent. (Compl. ¶50).
- Accused Features: The Belkin Wireless Charger is accused of infringing by allegedly utilizing "internal monitoring and switch circuitry features" claimed by the patent. (Compl. ¶35).
III. The Accused Instrumentality
Product Identification
- Belkin BoostCharge USB-C Wall Charger 20W ("Belkin Wall Charger") (Compl. ¶22).
- Belkin BoostCharge Wireless Charging Dual Pads 10W ("Belkin Wireless Charger") (Compl. ¶29).
Functionality and Market Context
- The Belkin Wall Charger is a compact power adapter that plugs into a standard AC wall outlet to charge devices like mobile phones via a USB-C cable. The complaint alleges it employs a "reduced plug-size" design so that it does not block or interfere with the use of adjacent outlets. (Compl. ¶24). The complaint provides a photograph of the Belkin Wall Charger plugged into a wall outlet, illustrating its compact size relative to the outlet. (Compl. p. 6).
- The Belkin Wireless Charger is a Qi-compliant wireless charging pad that powers devices via electromagnetic induction. (Compl. ¶30, ¶33). The complaint alleges it contains "internal monitoring circuitry" with a "novel load sensing portion" to detect when a device is fully charged and to control the flow of current, thereby determining an "off" state for the device. (Compl. ¶34). The complaint provides photographs of the Belkin Wireless Charger, including its retail packaging and the device itself. (Compl. p. 7).
IV. Analysis of Infringement Allegations
RE48,794 E Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a charger plug... including a housing... a DC connector... and first and second separate blade members secured within the housing... | The Belkin Wall Charger is a charger that connects between an AC power source and a device to be charged. It has a housing, blades for an outlet, and a USB-C port (DC connector). | ¶23 | col. 13:17-36 |
| i) being sized so that the charger plug housing comprises a longitudinal length... less than 2.0 inches, a width of the housing outer profile being less than 1.75 inches, and | The Belkin Wall Charger has a longitudinal length of approximately 1.296 inches and a width of approximately 1.256 inches. | ¶28 | col. 14:1-5 |
| ii) the outer profile having no interference with an adjacent receptacle of the power source... | The Belkin Wall Charger "does not block or interfere with the use of adjacent outlets." | ¶24 | col. 14:6-12 |
| so that when space is limited... the power cord plug end may be conveniently received by the DC connector... and can be conveniently removed... while leaving the charger plug connected... | The size and shape of the Belkin Wall Charger are such that a power cord can be easily inserted and removed while the charger is plugged in. | ¶25 | col. 14:9-15 |
- Identified Points of Contention:
- Factual Question: The infringement analysis for the '794 patent will likely depend on factual evidence. A key question is whether the defendant's measurements of the Belkin Wall Charger's dimensions align with the plaintiff's allegations and fall within the claimed ranges.
- Scope Question: A point of contention may arise over the functional language "no interference with an adjacent receptacle... in all available orientations." The court may need to determine the scope of this phrase, for instance, what constitutes "interference" (e.g., any physical overlap versus preventing the use of a standard plug) and what range of "orientations" (e.g., standard duplex outlets, power strips) is covered by the claim.
7,910,833 Infringement Allegations
| Claim Element (from Independent Claim 24) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A power device for supplying power to an electronic device... comprising... power circuitry for converting the input power... and for determining an "off" state... | The Belkin Wireless Charger is a charger that connects to AC power and charges a mobile device. It contains internal circuitry that controls the flow of current and determines an "off" state. | ¶30, ¶34 | col. 13:30-38 |
| switching circuitry operable to electrically activate the power circuitry to the "on" state | The accused product's internal circuitry includes switches that control the flow of current based on the charge-status of the mobile device. | ¶34 | col. 13:39-40 |
| a load sensing portion operable to sense one or more pulses and determine the power or load being drawn... by measuring the frequency of the pulses. | The Belkin Wireless Charger's internal circuitry "senses the frequency of pulses rather than sensing the magnitude of a voltage and/or current, to determine the load being drawn, and to determine an 'off' state for the device." | ¶34 | col. 13:41-44 |
- Identified Points of Contention:
- Technical Question: The central dispute will be highly technical: does the accused Qi-standard wireless charger actually determine its load state by "measuring the frequency of the pulses," as specifically required by the claim? Or does it use a different method permissible under the Qi standard, such as monitoring voltage, current magnitude, or data packets, which may not read on the claim language?
- Evidentiary Question: Plaintiff will need to produce evidence, likely through reverse engineering and expert testimony, demonstrating that the specific operational mode of the Belkin Wireless Charger matches the narrow technical mechanism described in the patent and required by the claim.
V. Key Claim Terms for Construction
For the '794 Patent
- The Term: "no interference with an adjacent receptacle" (from Claim 1)
- Context and Importance: This functional language is central to the infringement analysis. The definition of "interference" will determine whether the accused product's physical footprint, which the complaint alleges is non-interfering, actually meets the claim limitation.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent background discusses the general problem of plugs that "block or interfere with the use of adjacent outlets," which may support an interpretation that "no interference" means simply that a standard, second plug can be successfully inserted and used in the adjacent socket. (Compl. ¶11; '794 Patent, col. 1:45-49).
- Evidence for a Narrower Interpretation: A defendant might argue that the term requires complete clearance from the adjacent receptacle's faceplate area, not just functional non-blocking. The patent's focus on specific dimensional reductions could be used to argue that the term implies more than just accommodating another plug. (e.g., '794 Patent, Fig. 1).
For the '833 Patent
- The Term: "a load sensing portion... determin[ing] the... load... by measuring the frequency of the pulses" (from Claim 24)
- Context and Importance: This term defines the core technical mechanism of the invention. Whether the accused product infringes will likely depend entirely on how its load-detection technology is characterized relative to this language. Practitioners may focus on this term because the Qi wireless charging standard involves complex communication protocols, and it is a significant open question whether its operation can be fairly described as "measuring the frequency of pulses."
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification states the load sensing device "senses the pulse width and recognizes how slow or fast the pulse is repeated to determine the load." ('833 Patent, col. 9:36-39). Plaintiff may argue this supports a broad reading where any detection of the rate of a repeating signal qualifies as measuring frequency.
- Evidence for a Narrower Interpretation: The patent figures and description show a specific circuit for monitoring pulses from a transformer's secondary winding to drive an auto-shutoff switch. ('833 Patent, Fig. 11). A defendant could argue the term is limited to this specific type of analog pulse-counting and does not cover the digital communication and control packets used in the Qi standard.
VI. Other Allegations
- Indirect Infringement: The complaint does not plead any counts for indirect infringement (i.e., induced or contributory infringement).
- Willful Infringement: The prayer for relief includes a request for a finding that Defendant's infringement was "willful, wanton, and deliberate," which could lead to enhanced damages. (Compl. p. 11, ¶C). The body of the complaint, however, does not allege specific facts to support this claim, such as pre-suit knowledge of the patents.
VII. Analyst’s Conclusion: Key Questions for the Case
- Technical Operation vs. Claim Language: A key evidentiary question will be one of functional operation: does the accused Belkin Wireless Charger, which operates under the Qi wireless charging standard, utilize a load-sensing mechanism that can be technically and legally defined as "measuring the frequency of the pulses" as narrowly required by Claim 24 of the '833 patent?
- Factual Measurement vs. Claim Scope: The dispute over the Belkin Wall Charger will likely be a fact-intensive inquiry: do the charger's precise, measured physical dimensions fall within the length and width limitations of Claim 1 of the '794 patent, and does its design satisfy the functional requirement of "no interference" with adjacent outlets under all required orientations?
- Impact of Post-Grant History: A critical underlying issue, unmentioned in the complaint, will be the extensive post-grant proceedings for the '833 and '648 patents. The resulting claim cancellations, disclaimers, and amendments have significantly narrowed the scope of the asserted claims, and this prosecution history will be central to claim construction and may provide Defendant with strong arguments for non-infringement or invalidity.