Modulus Systems LLC v. KAGA FEI Co., Ltd.

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Modulus Systems LLC (Delaware)
  • Defendant: KAGA FEI CO., Ltd. (Japan)
  • Plaintiff’s Counsel: KENT & RISLEY LLC
• Case Identification: 2:23-cv-00240, E.D. Tex., 05/27/2023
• Venue Allegations: Venue is asserted on the basis that the defendant is a foreign corporation.
• Core Dispute: Plaintiff alleges that Defendant infringes a patent related to the physical design and operating methods of configurable radio frequency (RF) modules.
• Technical Context: The technology concerns compact, multi-mode RF modules used in wireless devices, designed to operate reliably in the crowded 2.4 GHz frequency band by minimizing physical size and mitigating interference from protocols like Wi-Fi.
• Key Procedural History: The complaint alleges that Plaintiff provided Defendant with notice of infringement via a letter dated May 18, 2023, nine days prior to filing the lawsuit.

Case Timeline

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

U.S. Patent No. 8,610,573 - Radio Frequency Module and Methods of Transmitting/Receiving Data, issued December 17, 2013

The Invention Explained

• Problem Addressed: The patent’s background section identifies several technical challenges with prior art RF modules: (1) physical size limitations, as matching/filtering components were typically placed in a linear alignment with the antenna, making miniaturization difficult ('573 Patent, col. 1:29-34); (2) interference from ubiquitous Wi-Fi systems in the 2.4 GHz band, which often required complex, power-intensive "handshaking" protocols that limited communication to single point-to-point links ('573 Patent, col. 1:40-54); and (3) limited configurability, often requiring expert knowledge to adapt modules for different tasks ('573 Patent, col. 1:35-39).
• The Patented Solution: The invention claims to solve these problems through a novel physical layout and new transmission methods. Structurally, it describes a compact module where a chip antenna is placed on the circuit board outside of a radio frequency shield, running parallel to a matching/filtering network located inside the shield. This arrangement, connected by a feed point, creates what the patent calls a "generally U-shape configuration" that allows the shield and antenna to function together as a larger, more effective antenna in a smaller footprint ('573 Patent, col. 2:8-18, col. 6:35-43). The patent also discloses methods for transmitting data on frequencies situated between standard Wi-Fi channels to avoid interference ('573 Patent, col. 2:18-22).
• Technical Importance: This approach sought to enable the development of smaller, more power-efficient, and more versatile wireless devices capable of reliable point-to-multipoint communication in increasingly congested radio environments ('573 Patent, col. 1:52-61).

Key Claims at a Glance

• The complaint asserts "one or more claims" of the ’573 Patent but does not specify which claims are asserted in the complaint body (Compl. ¶9). The patent contains two independent claims, an apparatus claim (Claim 1) and a method claim (Claim 11).
• Independent Claim 1 (Apparatus) includes the following essential elements:
  • A base member (e.g., a printed circuit board).
  • A transceiver assembly on the board, which includes a transceiver and a matching/filtering network.
  • The matching/filtering network comprises a "plurality of passive series connected electrical components in a linear arrangement."
  • A ground plane on the board's surface.
  • A radio frequency shield coupled to the ground plane and covering the transceiver assembly.
  • A chip antenna located on the board's surface "outside of the shield" and extending "generally parallel" with the matching/filtering network.
  • A radio feed point connecting the antenna and network, where the antenna, network, and feed point together form a "generally U-shape."
• The complaint does not explicitly reserve the right to assert dependent claims.

III. The Accused Instrumentality

Product Identification

• The complaint does not name specific accused products in its main body. It refers to "Exemplary Defendant Products" that are identified in a chart incorporated as Exhibit B (Compl. ¶9). This exhibit was not filed with the public version of the complaint.

Functionality and Market Context

• The complaint does not provide sufficient detail for analysis of the accused products' functionality or market context.

IV. Analysis of Infringement Allegations

The complaint alleges that the "Exemplary Defendant Products" satisfy all elements of an "Exemplary '573 Patent Claim" as detailed in a claim chart attached as Exhibit B (Compl. ¶10). However, Exhibit B was not filed with the complaint. Therefore, the specific mapping of accused product features to claim elements is not available for analysis from the provided documents. The complaint does not provide sufficient detail for analysis of potential points of contention.

No probative visual evidence provided in complaint.

V. Key Claim Terms for Construction

The Term: "generally U-shape configuration" (from Claim 1)

• Context and Importance: This term describes the novel physical layout of the antenna, feed point, and matching/filtering network, which is a central feature of the claimed invention. The construction of this geometric and relational term will be critical to determining whether the physical layout of the accused products falls within the scope of the claim.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The patent does not provide a precise mathematical or geometric definition for "generally U-shape," instead using a descriptive term ('573 Patent, col. 2:16-18). This may support a construction that is not strictly limited to the exact angles or proportions shown in the drawings.
  • Evidence for a Narrower Interpretation: A party could argue the term is defined by the embodiments shown in the figures, such as Figure 3, which depicts a specific spatial relationship where the antenna (15) and matching/filtering network (62) are parallel and connected by the feed point (75) ('573 Patent, Fig. 3). The specification links this shape directly to the parallel arrangement of the antenna and the network ('573 Patent, col. 11:51-60).

The Term: "outside of the shield" (from Claim 1)

• Context and Importance: This term defines the location of the chip antenna relative to the radio frequency shield. As the claimed invention's compactness and performance rely on the interplay between the shielded and unshielded components, the boundary of the "shield" is a key aspect of infringement analysis.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: This could be construed simply as any location not physically enclosed by the walls of the shield (22) ('573 Patent, col. 4:25-29).
  • Evidence for a Narrower Interpretation: The specification states that the shield and antenna "effectively function together as a single antenna structure" ('573 Patent, col. 6:38-40). This functional relationship could be used to argue for a more nuanced definition of "outside," potentially excluding arrangements where the antenna is partially integrated with or positioned directly underneath an overhang of the shield, even if not fully enclosed.

VI. Other Allegations

Indirect Infringement

• The complaint alleges inducement of infringement, stating that Defendant encourages infringement by "distributing product literature and website materials" and by inducing "distributors, end users, and others to offer, sell, or use its products in the customary and intended manner" (Compl. ¶9).

Willful Infringement

• The complaint alleges that Defendant had knowledge of the ’573 patent at least as of May 18, 2023, due to a notice letter (Compl. ¶8). It further makes a conclusory allegation that Defendant "knows" its actions infringe the patent, which may form a basis for willfulness based on conduct after receiving that notice (Compl. ¶9).

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

• A core issue will be one of definitional scope: can the descriptive term "generally U-shape configuration", which is central to Claim 1, be construed to read on the physical layout of the Defendant's RF modules? The outcome will likely depend on the degree of similarity between the accused products and the patent's disclosed embodiments.
• A second key question will be evidentiary: given the bare-bones nature of the complaint and the absence of a public claim chart, the case will turn on whether Plaintiff can produce sufficient technical evidence during discovery to map the specific components and layout of the accused products to each limitation of the asserted claims.
• Finally, a significant question for damages will be willfulness: what actions, if any, did the Defendant take after receiving the alleged notice letter on May 18, 2023? The defendant's conduct during the period between notice and potential resolution will be central to the court's willfulness analysis.