Comarco Wireless Systems LLC v. HP Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Comarco Wireless Systems LLC (Texas)
  • Defendant: HP, Inc. (Delaware)
  • Plaintiff’s Counsel: Direction IP Law
• Case Identification: 2:25-cv-00420, E.D. Tex., 04/18/2025
• Venue Allegations: Plaintiff alleges venue is proper in the Eastern District of Texas because Defendant maintains a place of business in the district and has allegedly committed acts of infringement there.
• Core Dispute: Plaintiff alleges that chargers sold with Defendant’s laptops and mobile workstations infringe three patents related to power supply systems that communicate with a portable device to determine and deliver an appropriate power level.
• Technical Context: The technology addresses the need for intelligent power adapters that can safely charge a variety of portable electronic devices from different power sources by negotiating the correct power output, a key function in modern universal charging standards.
• Key Procedural History: Plaintiff alleges it sent Defendant a notice letter with claim charts on September 15, 2023, asserting infringement of the patents-in-suit, which may form the basis for its allegations of willful infringement.

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"

• Patent Identification: U.S. Patent No. 9,413,187, issued August 9, 2016.

The Invention Explained

• Problem Addressed: The patent's background describes the technical problem of a user connecting a portable device to different types of DC power sources, such as an automobile outlet versus an airplane "EMPOWER" outlet, which provide different voltages. Using the wrong physical connector or a flawed connector could send an incorrect signal to the device, potentially causing it to recharge its battery when it shouldn't, leading to overheating or damage (Compl. ¶10; ’187 Patent, col. 2:38-51).
• The Patented Solution: The invention is an external power supply system that determines the appropriate power level to deliver through a "handshake" process with the portable device (Compl. ¶11). The system uses a four-conductor connector to transfer DC power, ground, a first signal from the device to the power supply, and a second, analog signal back to the device. This second analog signal has a "parameter level" that indicates the "potential power output level" of the supply, allowing the device to control its battery charging accordingly (’187 Patent, Abstract; col. 4:26-47).
• Technical Importance: This approach enables a universal power adapter to intelligently and safely charge various devices from multiple power sources by communicating its specific capabilities to the device being charged (Compl. ¶11).

Key Claims at a Glance

• The complaint asserts independent claim 8 and dependent claim 9 (Compl. ¶17).
• The essential elements of independent 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" with four conductors for transferring DC power, ground, the first signal, and the second signal.
  • Wherein the data circuitry provides the second signal in response to the first, with the second signal being an "analog signal having a parameter level" that indicates the power supply's "potential power output level".

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

• Patent Identification: U.S. Patent No. 10,855,087, issued December 1, 2020.

The Invention Explained

• Problem Addressed: The patent addresses the same technical problem as the ’187 Patent: the risk of battery damage when portable devices are charged from various DC sources without a reliable way to communicate power capabilities between the source and the device (’087 Patent, col. 2:1-10).
• The Patented Solution: The invention is a power supply system with power and data circuitry that communicates with a portable device over a four-conductor connection. The system receives a first signal from the device and, in response, provides a second signal back to it (’087 Patent, Abstract). The key claimed function of this second signal is that it has a "parament [sic] level that is usable by the portable electronic device in connection with control of charging a rechargeable battery" based on the power provided (’087 Patent, col. 11:18-24).
• Technical Importance: This system provides a method for a power supply to communicate its properties to a connected device, enabling safer and more efficient charging across different platforms (Compl. ¶11).

Key Claims at a Glance

• The complaint asserts independent claim 1 and dependent claims 5-7, 11, and 15-17 (Compl. ¶44).
• The essential elements of independent claim 1 include:
  • A power supply system comprising "power circuitry" and "data circuitry".
  • The data circuitry is configured to receive a first signal from and provide a second signal to a portable electronic device.
  • The circuitry is coupled to the device via a connector with four conductors.
  • The conductors transfer DC power, ground, the first signal, and the second signal.
  • Wherein the data circuitry provides the second signal having a "parament level that is usable" by the device to control charging based on the provided DC power.

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

• Patent Identification: U.S. Patent No. 10,951,042, issued March 16, 2021.
• Technology Synopsis: This patent claims the invention from the perspective of the portable electronic device rather than the external power supply. It describes a portable device with a rechargeable battery and circuitry configured to provide a first signal to a power supply and receive a second signal from the supply, where the second signal has a parameter level used by the device's data circuitry to control battery charging (Compl. ¶82).
• Asserted Claims: Independent claim 1 and dependent claims 5-6, 11, and 15-16 are asserted (Compl. ¶81).
• Accused Features: The complaint accuses HP's portable electronic devices (e.g., HP EliteBook, ZBook) of infringement. It alleges that these devices contain the claimed rechargeable battery and circuitry for controlling charging based on signals exchanged with a power supply, particularly one compliant with the USB Battery Charging 1.2 standard (Compl. ¶¶ 83-84).

III. The Accused Instrumentality

Product Identification

• The complaint names a wide array of HP laptops and mobile workstations, including models from the HP EliteBook, ZBook, and ProBook lines. The allegations target both the external power chargers sold with these devices and, for the ’042 patent, the portable electronic devices themselves (Compl. ¶¶ 17, 44, 81).

Functionality and Market Context

• The infringement allegations center on the functionality of the accused chargers and devices when operating under established industry charging standards, including USB Battery Charging (BC) 1.2, USB Power Delivery, and Qualcomm Quick Charge (Compl. ¶¶ 19, 25, 32). The core accused functionality is the "Primary Detection" method described in the USB BC 1.2 specification, where a device and charger use the D+ and D- data lines to negotiate and establish a charging state (Compl. ¶¶ 21, 48, 85). The complaint includes a diagram from a USB specification illustrating the power capabilities associated with different USB standards, including the 7.5W power level for USB BC 1.2 (Compl. p. 38). The accused products represent major commercial product lines for HP.

IV. Analysis of Infringement Allegations

9,413,187 Infringement Allegations

Identified Points of Contention

• Technical Questions: The complaint's theory for the "second signal" repeatedly relies on the doctrine of equivalents, characterizing the D- signal as a "modified signal originating in the portable electronic device" (Compl. ¶21, ¶40). A central question will be whether the accused functionality—shorting the D+ and D- lines through a resistor—constitutes "providing" a second signal as claimed, or if the D- signal is merely a voltage-dropped version of the first signal that never truly originates from the power supply's circuitry.
• Scope Questions: The infringement analysis will likely focus on whether the term "data circuitry" can be construed to cover a passive resistor used for port detection, as alleged by Plaintiff. A diagram in the complaint shows the circuitry for the USB BC 1.2 Primary Detection method, which will be central to this technical and legal dispute (Compl. p. 39).

10,855,087 Infringement Allegations

Identified Points of Contention

• Scope Questions: As with the ’187 patent, the core dispute may be whether the simple resistor-based detection in the USB BC 1.2 standard meets the claim limitation of "data circuitry... configured... to provide the second signal." The complaint presents a table from a USB specification summarizing power options, including the "Legacy charging" of USB BC 1.2, which will be scrutinized to determine if its operation matches the claim language (Compl. p. 200).
• Legal Questions: Independent claim 1 contains the term "parament level," which appears to be a typographical error for "parameter level." While often corrected by courts, this could become a minor point of contention in claim construction.

V. Key Claim Terms for Construction

• The Term: "data circuitry... to provide a second signal" (from ’187 Patent, Claim 8; ’087 Patent, Claim 1)

  • Context and Importance: This term is critical because Plaintiff’s infringement theory alleges that a passive resistor shorting the D+ and D- lines in the accused chargers constitutes data circuitry that "provides" the resulting D- signal. The complaint's repeated invocation of the doctrine of equivalents for this element suggests this will be a primary focus of dispute (Compl. ¶¶ 21, 52). Practitioners may focus on this term because its construction will determine whether the accused USB BC 1.2 functionality can literally infringe.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The specification discloses that the "analog circuitry may contain passive or active components" (’187 Patent, col. 4:32-33), which may support Plaintiff's view that a simple passive component like a resistor can constitute the claimed circuitry.
    • Evidence for a Narrower Interpretation: The detailed description and figures illustrate embodiments where "Control circuitry" actively generates signals to program the power output (’087 Patent, Fig. 3, item 370; col. 4:5-15). A defendant may argue that "provide" implies active generation or origination within the circuitry, not the passive modification of a signal originating from the portable device itself.

• The Term: "analog signal having a parameter level to indicate ... the potential power output level" (’187 Patent, Claim 8)

  • Context and Importance: The infringement argument hinges on the voltage on the D- pin qualifying as this claimed signal. The question is whether this voltage level, which is a consequence of a short, actively "indicates" the power supply's capability or is simply a state that the device interprets.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The patent abstract broadly describes the function as providing an "output signal... usable by the PED in connection with control of charging," which could encompass any signal that enables such control (’087 Patent, Abstract).
    • Evidence for a Narrower Interpretation: The specification describes a system where the signal can be used to "set the magnitude of Vout and limit the amount of current," suggesting a more direct and instructive signal than a simple voltage drop that merely identifies a port type (’187 Patent, col. 4:38-42).

VI. Other Allegations

• Indirect Infringement: The complaint alleges inducement and contributory infringement against HP. The factual basis is HP's alleged advertising, sale, and provision of instructions for the accused chargers and laptops, with the knowledge that customers would use them in an infringing manner (Compl. ¶¶ 39-41, 76-78).
• Willful Infringement: Willfulness is alleged based on pre-suit knowledge. The complaint states that HP received a letter and claim charts detailing the alleged infringement on September 15, 2023, and continued its infringing activities despite knowing of an "unjustifiably high risk of infringement" (Compl. ¶¶ 42, 79, 108).

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

• A core issue will be one of technical and definitional scope: can the claim term "data circuitry... to provide a second signal", which is described in the patents in the context of active control circuits, be construed to cover the passive resistor-based port detection mechanism of the accused USB BC 1.2 standard? The complaint's reliance on the doctrine of equivalents suggests this is the central point of contention.
• A key evidentiary question will be one of functional operation: does the voltage drop on the D- data line in the accused products perform the same function as the claimed "analog signal having a parameter level to indicate... the potential power output level"? The case may turn on whether this voltage merely allows the device to detect a port type or whether it truly "indicates" a specific power level from the supply itself, as the claims may require.
• The allegation of willfulness will depend on the sufficiency of the September 15, 2023 notice letter. The court will examine whether the provided claim charts gave HP actual, specific knowledge of its alleged infringement, making its subsequent conduct objectively reckless.