CommPlex Systems LLC v. Acer Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: CommPlex Systems LLC (New Mexico)
  • Defendant: Acer Inc. (Taiwan)
  • Plaintiff’s Counsel: Rabicoff Law LLC
• Case Identification: 2:25-cv-00336, E.D. Tex., 04/04/2025
• Venue Allegations: Plaintiff alleges venue is proper because Defendant has an established place of business within the Eastern District of Texas and has committed acts of alleged infringement in the District.
• Core Dispute: Plaintiff alleges that certain unidentified products made and sold by Defendant infringe a patent related to communication systems that use multiple orthogonal frequencies to transmit digital data.
• Technical Context: The lawsuit concerns methods for high-efficiency digital data transmission, a foundational technology in modern wireless and wired communication devices.
• Key Procedural History: The complaint does not mention any prior litigation, licensing history, or administrative proceedings involving the patent-in-suit. The claim for willfulness is predicated on knowledge gained from the service of the complaint itself.

Case Timeline

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

U.S. Patent No. 7,864,900, "Communication system for sending and receiving digital data," issued Jan. 4, 2011

The Invention Explained

• Problem Addressed: The patent's background section describes challenges with conventional Frequency Shift Keying (FSK) communication, where inaccuracies in determining a signal's center frequency can lead to data transmission errors, particularly in narrow-band systems (’900 Patent, col. 2:60-64). The patent notes a need for a system that can efficiently transmit data using multiple orthogonal frequencies to improve performance (’900 Patent, col. 1:40-44).
• The Patented Solution: The invention proposes a communication system employing a "Multiple Orthogonal locked frequencies Narrow Band Frequency Shift Keying (Mary-NBFSK) system" (’900 Patent, col. 4:9-12). Instead of a simple binary FSK (where two frequencies represent a 0 or 1), this system uses a larger set of available orthogonal frequencies and transmits a specific combination of them simultaneously to represent a larger block of data, thereby increasing the "code density and data rate per Hz of bandwidth" (’900 Patent, col. 7:62-65). A key aspect is the use of a "look up table" to map data bits to specific frequency combinations (’900 Patent, col. 6:39-43).
• Technical Importance: This approach aims to achieve higher data rates within a given bandwidth and with greater reliability compared to simpler, parallel FSK systems, which is a persistent goal in radio frequency communications (’900 Patent, col. 4:19-22).

Key Claims at a Glance

• The complaint asserts "one or more claims," including "exemplary claims" identified in an attached exhibit (Compl. ¶11). Independent claim 1 is the broadest claim of the patent.
• Independent Claim 1 requires:
  • A communication system with a transmitter and a receiver.
  • A "general binary coded Orthogonal Frequency-Division Multiplexing carrier scheme" between the transmitter and receiver to increase code density and data rate.
  • A "plurality of narrow band carrier frequencies" that are orthogonal and transmitted in a binary code to represent data.
  • The narrow band frequencies must have a separation "of the order of 0.1 MHz" and provide a bandwidth "of the order of 3.2 MHz for 32 carriers," allowing transmission of "at least 6 Mbps in a 2 of 32 Orthogonal Frequency-Division Multiplexing" configuration.
• The complaint does not explicitly reserve the right to assert dependent claims, but its general pleading style suggests this possibility.

III. The Accused Instrumentality

Product Identification

The complaint does not name any specific accused products. It refers generally to "Defendant products identified in the charts" which it calls the "Exemplary Defendant Products" (Compl. ¶11). These charts are part of an exhibit that was not included with the complaint document.

Functionality and Market Context

The complaint alleges that Defendant makes, uses, sells, and imports these "Exemplary Defendant Products" (Compl. ¶11). It further alleges that Defendant provides "product literature and website materials" that instruct end users on how to use these products in an infringing manner (Compl. ¶14). The complaint does not provide sufficient detail for analysis of the accused products' technical functionality or market context.

IV. Analysis of Infringement Allegations

The complaint’s substantive infringement allegations are contained entirely within "Exhibit 2," which it incorporates by reference (Compl. ¶16-17). As this exhibit was not provided, a detailed element-by-element analysis is not possible based on the complaint alone. The narrative allegations state that the "Exemplary Defendant Products" infringe "literally or by the doctrine of equivalents" by practicing the technology claimed by the '900 Patent and that these products "satisfy all elements of the Exemplary '900 Patent Claims" (Compl. ¶11, ¶16). No probative visual evidence provided in complaint.

Identified Points of Contention

• Scope Questions: A central question will be whether the accused products, once identified, implement what can be properly characterized as an "Orthogonal Frequency-Division Multiplexing carrier scheme" as required by claim 1. The defense may argue its technology is distinct from the specific scheme described in the patent.
• Technical Questions: What evidence does the Plaintiff possess to demonstrate that the accused products meet the specific numerical limitations of claim 1, such as the carrier separation ("of the order of 0.1 MHz"), total bandwidth ("of the order of 3.2 MHz"), and data rate ("at least 6 Mbps")? The complaint itself provides no such evidence.

V. Key Claim Terms for Construction

• The Term: "Orthogonal Frequency-Division Multiplexing carrier scheme"
• Context and Importance: This term appears in claim 1 and describes the core architecture of the invention. Its construction will be critical, as the infringement case depends on mapping this term onto the functionality of the accused products. Practitioners may focus on this term because its precise technical meaning could be disputed, potentially distinguishing the patented method from other multiplexing techniques used by the defendant.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The patent equates this scheme with its "Multiple Orthogonal locked frequencies Narrow Band Frequency Shift Keying (Mary-NBFSK) system," suggesting the term could cover a range of systems that use multiple locked orthogonal frequencies to encode data, not just systems formally labeled "OFDM" in the industry (’900 Patent, col. 4:9-12).
  • Evidence for a Narrower Interpretation: The claim itself ties the scheme to specific performance metrics (e.g., "transmit at least 6 Mbps in a 2 of 32" configuration), which could be used to argue that the term is limited to systems capable of meeting these exact parameters (’900 Patent, col. 9:8-10).

VI. Other Allegations

Indirect Infringement

The complaint alleges induced infringement, stating that Defendant distributes "product literature and website materials inducing end users and others to use its products in the customary and intended manner that infringes the '900 Patent" (Compl. ¶14).

Willful Infringement

The complaint alleges that service of the complaint itself provides "actual knowledge of infringement" and that Defendant's continued activities thereafter constitute willful infringement (Compl. ¶13-14). This is a post-suit willfulness allegation.

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

1. A primary issue will be one of identification and evidence: Given the complaint's reliance on an external, unprovided exhibit, a threshold question is which specific Acer products are accused of infringement and what technical evidence Plaintiff will produce to show these products meet the detailed numerical and functional limitations of the asserted claims, particularly the frequency separation and data rate parameters of claim 1.

2. The case will likely involve a significant dispute over claim scope: Can the term "Orthogonal Frequency-Division Multiplexing carrier scheme," as defined and used within the '900 Patent, be construed to read on the communication protocols used in Defendant’s modern commercial products, or will Defendant be able to distinguish its technology as falling outside the patent's specific implementation?