Modulus Systems LLC v. Zebra Tech Corp

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Modulus Systems LLC (Delaware)
  • Defendant: Zebra Technologies Corporation (Delaware)
  • Plaintiff’s Counsel: KENT & RISLEY LLC
• Case Identification: 6:23-cv-00335, W.D. Tex., 05/09/2023
• Venue Allegations: Plaintiff alleges venue is proper because Defendant maintains a regular and established place of business in the district and has committed alleged acts of patent infringement there.
• Core Dispute: Plaintiff alleges that certain of Defendant’s products infringe two patents related to antenna assemblies with integrated radio frequency (RF) modules.
• Technical Context: The technology involves integrating RF electronics directly into an antenna's housing to minimize signal loss, improve performance, and reduce the complexity of wireless devices.
• Key Procedural History: The complaint alleges that Plaintiff provided Defendant with notice of infringement via a letter dated April 14, 2023, less than one month before filing the suit. The two patents-in-suit share a priority application, with U.S. Patent No. 8,410,990 being a continuation-in-part of the application that issued as U.S. Patent No. 8,866,696.

Case Timeline

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

U.S. Patent No. 8,410,990 - Antenna with Integrated RF Module (issued Apr. 2, 2013)

The Invention Explained

• Problem Addressed: The patent describes the issue of signal loss, cost, and complexity associated with using coaxial cables to connect an external antenna to an internal RF module in wireless devices. It also notes that fully internal antennas can suffer from signal degradation due to obstruction (the "hand effect") and are incompatible with metal enclosures (’990 Patent, col. 1:12-51).
• The Patented Solution: The invention is an antenna assembly where the RF module is integrated into the same housing as the antenna itself. A key feature is a conductive sleeve surrounding the module that serves as a ground plane and shield, which, in combination with a specially configured spacer, creates a "radio frequency energy choke effect" to isolate the antenna and improve performance (’990 Patent, Abstract; col. 2:1-6).
• Technical Importance: This integrated design aims to create a more efficient and robust antenna by minimizing the distance and power loss between the RF processing electronics and the radiating antenna element (’990 Patent, col. 5:17-21).

Key Claims at a Glance

• The complaint asserts infringement of at least one "Exemplary '990 Patent Claim" but does not identify a specific claim number (Compl. ¶13). Independent claim 1 is representative and includes the following primary elements:
  • An antenna housing and an antenna located within it.
  • A radio frequency (RF) module located within the housing and connected to the antenna.
  • At least one electrical conductor for carrying processed signals.
  • A mounting base for connecting the assembly to an enclosure.
  • A conductive sleeve surrounding the RF module to provide a ground plane and shield.
  • A spacer located between the housing and the mounting base for "providing a radio frequency energy choke effect."

U.S. Patent No. 8,866,696 - Antenna with Integrated RF Module (issued Oct. 21, 2014)

The Invention Explained

• Problem Addressed: Similar to its related patent, the '696 Patent addresses the performance and cost disadvantages of separating antennas from RF modules with loss-inducing cables (’696 Patent, col. 1:5-42).
• The Patented Solution: The invention describes an antenna assembly that integrates the RF module (mounted on a printed circuit board, or PCB) with the antenna inside a single housing. This integrated unit connects to a main device using a "non-coaxial cable assembly" designed to carry processed, "non-radio frequency signals" (such as logic-level or audio signals) over long distances without the significant loss characteristic of RF signals (’696 Patent, Abstract; col. 2:4-25; col. 8:29-44).
• Technical Importance: This approach allows the sensitive RF components to be co-located with the antenna for maximum efficiency, while permitting the integrated unit to be placed far from the main device using inexpensive, standard, non-coaxial wiring (’696 Patent, col. 6:25-42).

Key Claims at a Glance

• The complaint asserts infringement of at least one "Exemplary '696 Patent Claim" without specifying a claim number (Compl. ¶21). Independent claim 1 is representative and includes the following primary elements:
  • An antenna housing containing an RF module (with a PCB) and an antenna.
  • A conductive sleeve surrounding the PCB and RF device, connected to the PCB to provide a ground plane.
  • A conductive mounting base connected to the housing and the sleeve to extend the ground plane.
  • A "non-coaxial cable assembly" extending through the mounting base, including wires for power and a wire "operable to conduct non-radio frequency signals... without significant signal loss."

III. The Accused Instrumentality

Product Identification

The complaint does not identify the accused products by name in the main body of the document. It refers to them as "Exemplary Defendant Products" that are allegedly identified in Exhibits C and D (Compl. ¶13, ¶21). These exhibits were not filed with the complaint.

Functionality and Market Context

The complaint does not provide any details regarding the specific functionality, operation, or market context of the accused products.

IV. Analysis of Infringement Allegations

The complaint alleges that infringement is detailed in claim charts attached as Exhibits C and D, but these exhibits are not included in the public filing (Compl. ¶18, ¶26). The complaint itself offers only conclusory statements that the "Exemplary Defendant Products practice the technology claimed" and "satisfy all elements" of an exemplary claim from each patent (Compl. ¶17, ¶25). As such, the complaint does not provide sufficient detail for a meaningful analysis of the infringement allegations.

No probative visual evidence provided in complaint.

Identified Points of Contention

Based on the patent claims, the dispute may center on the following questions:

• Functional Questions ('990 Patent): Does any component in the accused products function as a "spacer... for providing a radio frequency energy choke effect" as required by claim 1 of the '990 Patent? The existence and function of this "choke effect" may be a central point of technical disagreement.
• Technical Questions ('696 Patent): Do the accused products utilize a "non-coaxial cable assembly" to transmit "non-radio frequency signals" from an integrated antenna module? The analysis will likely focus on the physical nature of the cable and the technical characteristics of the signals it carries.

V. Key Claim Terms for Construction

• Term 1 ('990 Patent): "a spacer... for providing a radio frequency energy choke effect"

  • Context and Importance: This is a functional limitation that is central to the novelty of the invention described in the '990 Patent. Infringement will depend on whether a feature of the accused product meets both the structural ("spacer") and functional ("providing a... choke effect") requirements of this term.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The specification suggests the function is achieved by creating a "discontinuity in the flow of RF energy" via a "step S1" between the conductive sleeve and the wire bundle (’990 Patent, col. 9:15-21). This could support an argument that any structure creating such a dimensional step serves as a "spacer."
    • Evidence for a Narrower Interpretation: The patent depicts the spacer (206) as a discrete component with a specific length (L3) related to the antenna's wavelength (’990 Patent, Fig. 18; col. 9:4-6). This could support an argument that the term is limited to a distinct, physically separate component with specific dimensional properties, not just any non-conductive region or gap.

• Term 2 ('696 Patent): "non-coaxial cable assembly... operable to conduct non-radio frequency signals"

  • Context and Importance: This term distinguishes the invention from prior art that uses specialized RF coaxial cables. The definitions of "non-coaxial" and "non-radio frequency signals" will be critical to determining the scope of the claim.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The specification lists "logic level, analog, audio, and video signals" as examples of "non-radio frequency signals," suggesting the term covers a wide range of processed data (’696 Patent, col. 6:30-34). This could support a broad reading covering many standard multi-wire cables.
    • Evidence for a Narrower Interpretation: Parties may dispute what constitutes a "non-radio frequency signal," especially in the context of high-speed digital data that has RF characteristics. A defendant could argue the term requires signals to be fully baseband, without any high-frequency components, potentially narrowing the claim's reach.

VI. Other Allegations

• Indirect Infringement: The complaint alleges induced infringement for both patents. It asserts that Defendant, with knowledge of the patents (at least since April 14, 2023), distributes "product literature and website materials" that instruct and encourage customers to use the accused products in an infringing manner (Compl. ¶16, ¶24).
• Willful Infringement: The complaint alleges Defendant had "Actual Knowledge" of its infringement of both patents from a letter dated April 14, 2023. It further alleges that Defendant's infringement continued after receiving this notice, which forms the basis for a claim of post-filing willfulness (Compl. ¶14-15, ¶22-23).

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

1. An Evidentiary Question: As the complaint's infringement allegations rely entirely on non-public exhibits, the primary question is evidentiary: What specific products are accused, and what factual evidence will the plaintiff produce to show that those products contain the specific structural and functional elements of the patent claims?
2. A Question of Functional Definition: The case for the '990 patent may turn on claim construction of a functional limitation: Can the phrase "providing a radio frequency energy choke effect" be met by any structure that creates an RF discontinuity, or is it limited to a discrete, physically distinct "spacer" with dimensions tied to the antenna's operating frequency, as depicted in the patent's embodiments?
3. A Question of Technical Scope: For the '696 patent, a central issue will be the scope of "non-radio frequency signals." The court's interpretation will be critical: does this term encompass modern high-speed digital signals, which have RF properties, or is it restricted to lower-frequency analog or logic-level signals, thereby limiting the types of accused products that can infringe?