Comarco Wireless Systems LLC v. Panasonic Corp Of North America

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Comarco Wireless Systems LLC (Texas)
  • Defendant: Panasonic Corporation of North America (Delaware)
  • Plaintiff’s Counsel: Direction IP Law
• Case Identification: 2:25-cv-00425, E.D. Tex., 04/21/2025
• Venue Allegations: Plaintiff alleges venue is proper in the Eastern District of Texas because Defendant maintains regular and established places of business within the district.
• Core Dispute: Plaintiff alleges that Defendant’s chargers and portable electronic devices that support USB charging infringe three patents related to power supply systems that intelligently negotiate appropriate power levels.
• Technical Context: The technology concerns systems where a power supply and a portable electronic device communicate via signaling over a data connection to determine the power characteristics of the supply, enabling safe and efficient charging.
• Key Procedural History: The complaint alleges that Plaintiff provided Defendant with notice of infringement for all three patents-in-suit via a letter, including claim charts, on July 21, 2022, which forms the basis for the willfulness allegations.

Case Timeline

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

U.S. Patent No. 9,413,187 - "Power Supply System Providing Power and Analog Data Signal for Use by Portable Electronic Device to Control Battery Charging"

The Invention Explained

• Problem Addressed: The patent’s background describes the problem of safely charging portable electronic devices from various DC power sources, such as automobile and airplane outlets, which provide different voltages. A mismatch could prevent a device from charging or, in a worst-case scenario, cause a battery to overheat and catch fire, a particular danger on an airplane (Compl. ¶10; ’187 Patent, col. 1:37-2:6).
• The Patented Solution: The invention is a power supply system with data circuitry that engages in a two-way "handshake" with a portable device. The device sends a first signal to the power supply, and in response, the supply’s data circuitry provides a second, analog signal back to the device. This second signal has a "parameter level" (e.g., its current level) that indicates the potential power output of the supply, allowing the device to control battery charging accordingly (’187 Patent, col. 6:8-15, Abstract).
• Technical Importance: This approach allows a single, intelligent power adapter to be used safely with a variety of power sources and devices by enabling the end device to make an informed decision about whether and how to charge its battery (Compl. ¶11).

Key Claims at a Glance

• The complaint asserts independent claim 8.
• Essential elements of claim 8 include:
  • A power supply system external to a portable electronic device.
  • Power circuitry to provide DC power.
  • Data circuitry to receive a first signal from the device and provide a second signal to the device.
  • A connector on a cable end with four conductors for detachably mating with the device, transferring: (1) DC power, (2) ground reference, (3) the first signal from the device to the data circuitry, and (4) the second signal from the data circuitry to the device.
  • The data circuitry provides the second signal in response to the first signal, where the second signal is an analog signal with a parameter level indicating the power supply's potential power output.
• The complaint also asserts dependent claim 9 (Compl. ¶17).

U.S. Patent No. 10,855,087 - "Power Supply Systems"

The Invention Explained

• Problem Addressed: Similar to the ’187 Patent, this patent addresses the need for a power supply system that can intelligently communicate its capabilities to a portable electronic device to ensure safe charging (’087 Patent, col. 1:44-2:6).
• The Patented Solution: The ’087 Patent claims a power supply system with power and data circuitry coupled to a device via a four-conductor connector. The data circuitry receives a "first signal" from the device and, in coordination with that signal, provides a "second signal" back to the device. This second signal has a "parameter level" that the portable device can use to control the charging of its battery based on the power being provided (’087 Patent, Abstract). The configuration allows the device to assess the power source and adjust its charging behavior.
• Technical Importance: This system provides a flexible framework for power negotiation between a charger and a device, accommodating different power sources and device requirements through a defined signaling protocol (Compl. ¶11).

Key Claims at a Glance

• The complaint asserts independent claim 1.
• Essential elements of claim 1 include:
  • A power supply system with power circuitry and data circuitry.
  • The circuitry is configured to be coupled to a portable device via a connector with four conductors.
  • The data circuitry is configured to receive a first signal from the device and provide a second signal to the device.
  • The connector is configured to transfer: (1) DC power, (2) ground, (3) the first signal to the data circuitry, and (4) the second signal to the device.
  • The data circuitry, in coordination with the first signal, provides the second signal having a parameter level usable by the device to control battery charging.
• The complaint also asserts dependent claims 5-7, 11, and 15-17 (Compl. ¶44).

U.S. Patent No. 10,951,042 - "Power Supply Systems"

The Invention Explained

• Technology Synopsis: The ’042 Patent claims the other side of the transaction: a portable electronic device itself. The device contains a rechargeable battery, power circuitry to receive DC power, and data circuitry configured to provide a first signal to an external power supply and receive a second signal back. The second signal has a parameter level that the device’s data circuitry uses to control battery charging (’042 Patent, Abstract).

Asserted Claims and Accused Features

• Asserted Claims: Independent claim 1 and dependent claims 5-6, 11, and 15-16 (Compl. ¶81).
• Accused Features: The complaint accuses Panasonic’s portable electronic devices (e.g., LUMIX cameras, Toughbook computers) of infringing the ’042 Patent by implementing the claimed device-side charging control system when connected to a USB power supply (Compl. ¶¶81, 83).

III. The Accused Instrumentality

Product Identification

• The accused instrumentalities are Panasonic chargers ("Accused Chargers") sold with various cameras (e.g., LUMIX DC-GH8) and ruggedized computers (e.g., Toughbook 55), as well as the portable electronic devices themselves (Compl. ¶¶17, 44, 81).

Functionality and Market Context

• The complaint alleges that the Accused Chargers and Devices implement standardized USB charging protocols, including Battery Charging (BC) 1.2, USB Power Delivery (PD), and Qualcomm Quick Charge (QC) (Compl. ¶¶19, 25, 32, 68).
• The infringement theory centers on the allegation that these industry-standard protocols perform the same functions claimed in the patents. For example, under the BC 1.2 "Primary Detection" method, a portable device applies a voltage to a charger's D+ data line ("first signal"), and the charger responds by connecting the D+ and D- lines through a resistor, creating a voltage on the D- line ("second signal") that informs the device that it is connected to a dedicated charging port (Compl. ¶¶21, 23). The complaint includes a circuit diagram from the USB BC 1.2 specification illustrating this primary detection process (Compl. p. 17).

IV. Analysis of Infringement Allegations

U.S. Patent No. 9,413,187 Infringement Allegations

U.S. Patent No. 10,855,087 Infringement Allegations

Identified Points of Contention

• Scope Questions: A central question may be whether the claimed "analog signal having a parameter level to indicate... the potential power output level" can be construed to read on the binary-like signaling of the USB BC 1.2 standard, where a specific voltage on the D- line indicates that the port is a "Dedicated Charging Port" rather than conveying a range of potential power levels.
• Technical Questions: The complaint frequently asserts infringement under the doctrine of equivalents, stating that the accused D- signal is a "modified signal originating in the portable electronic device" (Compl. ¶21, ¶23). This suggests an anticipated defense that the accused chargers do not "provide" a second signal in response to the first, but merely modify the first signal by passing it through a resistor. The analysis may turn on whether this technical distinction creates a functional difference from what is claimed.

V. Key Claim Terms for Construction

• The Term: "analog signal having a parameter level" (’187 Patent, cl. 8); "second signal having a parameter level" (’087 Patent, cl. 1)
• Context and Importance: This term is the core of the claimed invention's "handshake." The infringement case depends on mapping this term to the voltage levels on the D- and D+ pins as defined in standards like USB BC 1.2. Practitioners may focus on whether a voltage that signals one of a few discrete states (e.g., standard port vs. charging port) meets the definition of an "analog signal" with a "parameter level" that indicates "potential power output level," or if the claims require a more continuously variable signal.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The specification of the parent ’187 patent states the parameter level can be, for example, a "current level" (’187 Patent, col. 6:31-32), which does not explicitly limit the term to only current or exclude other parameters like voltage. The use of "e.g." suggests this is an exemplary, not exhaustive, definition.
  • Evidence for a Narrower Interpretation: The embodiments described in the patents often focus on differentiating between two types of power sources (automobile vs. airplane) based on a voltage comparison (’187 Patent, col. 7:51-8:1). This context could be used to argue that the "parameter level" was intended to convey information about the source type rather than a granular "potential power output level," potentially narrowing the claim's scope.

VI. Other Allegations

• Indirect Infringement: The complaint alleges both induced and contributory infringement. The inducement theory is based on Defendant allegedly advertising and providing instructions for its products, thereby encouraging customers to use them in an infringing manner (e.g., Compl. ¶¶39-40, 77, 106).
• Willful Infringement: Willfulness is alleged based on Defendant’s purported actual knowledge of the patents-in-suit as of July 21, 2022, the date of a notice letter that allegedly included claim charts. The complaint alleges that Defendant continued its infringing conduct despite knowing of an unjustifiably high risk of infringement (e.g., Compl. ¶¶42, 79, 108).

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

• A core issue will be one of definitional scope: can claim terms like "analog signal having a parameter level," which originated in the context of custom power adapters, be construed to cover the standardized, discrete voltage-level signaling employed by modern USB charging protocols like BC 1.2? The outcome may depend on whether the function performed by the accused USB signaling is legally equivalent to that described in the patents.
• A key technical question will be one of signal origination: does an accused charger that connects the D+ and D- lines through a resistor, thereby creating a new voltage on the D- line, "provide a second signal" as claimed, or does it merely modify the first signal from the portable device? The complaint’s repeated reliance on the doctrine of equivalents for this element suggests this will be a central point of technical and legal dispute.
• An evidentiary question will be one of industry practice: how will the widespread adoption and standardization of the accused USB protocols (BC 1.2, Power Delivery, Quick Charge) influence the analyses of infringement and, potentially, damages or validity? The case juxtaposes bespoke patented technology against ubiquitous industry standards that allegedly practice the same invention.