CelluPlex LLC v. Panasonic Corp

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: CelluPlex LLC (NM)
  • Defendant: Panasonic Corporation (Japan)
  • Plaintiff’s Counsel: Rabicoff Law LLC
• Case Identification: 2:24-cv-00474, E.D. Tex., 06/26/2024
• Venue Allegations: Venue is alleged to be proper because the Defendant is a foreign corporation and has committed acts of patent infringement in the district.
• Core Dispute: Plaintiff alleges that certain unidentified Panasonic products infringe a patent related to an interface for connecting a cellular telephone to a wired telephone network.
• Technical Context: The technology concerns bridging wireless cellular networks with traditional wired telephone systems, allowing cellular calls to be managed through conventional landline or office phones.
• Key Procedural History: The complaint states that Plaintiff is the assignee of all rights to the patent-in-suit. No other procedural history is provided.

Case Timeline

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

• Patent Identification: U.S. Patent No. 7,177,664, "Bluetooth interface between cellular and wired telephone networks," issued on February 13, 2007.

The Invention Explained

• Problem Addressed: The patent describes a situation where cellular telephone users at their home or office might turn off their mobile devices to conserve battery, causing them to miss calls. It also notes the "inconvenience of fetching the cellular phone from a briefcase or a charging cradle" to use it when conventional wired phones are available (’664 Patent, col. 1:11-23).
• The Patented Solution: The invention is an "interconnect device" that forges a link between a cellular phone and a local wired telephone network, such as a home or office system (’664 Patent, Abstract). The device uses a short-range radio connection (preferably Bluetooth) to communicate with the user's cellular phone, and includes an interface that "emulates the behavior of a standard wired telephone trunk line to a central office" (’664 Patent, col. 2:16-18). This allows a user to place or receive calls from their cellular number using any standard wired telephone connected to the local network, effectively treating the cellular connection as another landline (’664 Patent, Fig. 1; col. 2:26-39).
• Technical Importance: The invention proposed a way to unify cellular and landline communications within a home or office, offering the convenience of a wired phone's ergonomics and features (e.g., multiple handsets, speakerphones) for cellular calls (’664 Patent, col. 2:35-39).

Key Claims at a Glance

• The complaint does not specify which claims are asserted, referring only to "Exemplary '664 Patent Claims" in a referenced exhibit not attached to the complaint (Compl. ¶13). Independent claim 1 is representative.
• Independent Claim 1: An interconnect device comprising, in combination:
  • a first short-range radio transceiver for exchanging voice and data signals with a second short-range radio transceiver in a cellular telephone
  • an interface connected between the wired network and the first transceiver for emulating a wired line connection
  • means for indicating the availability of an idle line
  • means for receiving a telephone number to be called from the wired telephone
  • means for transmitting the called number to the cellular telephone to initiate an outgoing call
  • means for handling an incoming call, including applying a ringing signal
  • means for establishing an audio transmission channel when the wired phone goes off-hook
  • means for disconnecting the channel when the wired phone goes on-hook

III. The Accused Instrumentality

• Product Identification: The complaint does not identify any specific accused product by name (Compl. ¶11). It refers to "Exemplary Defendant Products" that are purportedly identified in charts within an "Exhibit 2" (Compl. ¶13). This exhibit was not provided with the complaint.
• Functionality and Market Context: The complaint does not provide sufficient detail for analysis of the accused instrumentality's functionality or market context.

IV. Analysis of Infringement Allegations

The complaint alleges that "the Exemplary Defendant Products practice the technology claimed by the '664 Patent" and that claim charts comparing the claims to these products are included in Exhibit 2 (Compl. ¶13). As Exhibit 2 was not provided, a detailed analysis of the infringement allegations is not possible based on the filed complaint. The complaint's narrative infringement theory is conclusory, stating that the accused products "satisfy all elements of the Exemplary '664 Patent Claims" (Compl. ¶13).

No probative visual evidence provided in complaint.

• Identified Points of Contention: Given the technology, any future infringement analysis would likely raise several key questions:
  • Scope Questions: A central question may be whether modern cordless phone systems that link to cell phones (e.g., via Bluetooth) meet the limitation of an "interface connected between said wired network and said first short-range transceiver" (’664 Patent, col. 10:52-54). The defense may argue that integrated systems do not have a distinct "interface" connecting to a separate "wired network" in the manner contemplated by the patent.
  • Technical Questions: A key technical question will be whether the accused products perform the functions recited in the claim's "means-plus-function" limitations, such as "means for emulating a wired line connection" (’664 Patent, col. 10:54-57). The analysis would depend on whether the accused products' internal software and hardware architecture is structurally equivalent to the structures disclosed in the patent's specification for performing those functions.

V. Key Claim Terms for Construction

• The Term: "emulating a wired line connection from said wired telephone to a telephone central office" (’664 Patent, col. 10:54-57).

  • Context and Importance: This functional language is at the core of the invention. The scope of "emulating" will be critical. The patent was filed when distinct cellular and landline systems were the norm. How this term applies to modern, potentially more integrated systems that may not connect to a traditional "central office" will likely be a central point of dispute.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The specification describes the interface as emulating "the behavior of a standard wired telephone trunk line" (’664 Patent, col. 2:16-18), suggesting the term could cover any device that makes a cellular connection behave like a traditional landline to the user, regardless of the underlying technical implementation.
    • Evidence for a Narrower Interpretation: The specification describes specific behaviors being emulated, such as providing a dial tone, detecting an off-hook condition, and responding to DTMF tones (’664 Patent, col. 4:32-34; Fig. 4). A party could argue the term is limited to devices that replicate these specific signals and states, as opposed to devices that achieve a similar user experience through different technical means.

• The Term: "wired telephone network" (’664 Patent, col. 10:49-50).

  • Context and Importance: Practitioners may focus on this term because modern home telephone systems may differ from the "two-line wiring" or "PBX" systems explicitly depicted in the patent (’664 Patent, Figs. 1, 2). The definition will determine whether the claim reads on systems where a cordless phone base station communicates wirelessly with its own handsets, even if that base station also connects to a cellular phone.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The claim language itself is general. The specification states the network may be a "PBX, a key telephone system, or a variety of other existing wired telephone network facilities," suggesting the term is not limited to the specific examples shown (’664 Patent, col. 2:22-24).
    • Evidence for a Narrower Interpretation: The patent’s figures consistently show networks comprising multiple, physically wired telephone sets connected in parallel or to a Private Branch Exchange (PBX) (’664 Patent, Figs. 1, 2, 5). An argument could be made that the term requires a physical, multi-phone wired infrastructure, and would not cover a single cordless phone base station that links to a cell phone but only communicates wirelessly with its own dedicated handsets.

VI. Other Allegations

• Indirect Infringement: The complaint does not contain any allegations of indirect infringement.
• Willful Infringement: The body of the complaint does not allege willful infringement or provide facts related to pre-suit knowledge. However, the prayer for relief requests a judgment that the case be declared "exceptional" and for an award of attorneys' fees, which is often associated with findings of willful infringement or litigation misconduct (Compl. ¶15.E.i).

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

1. Evidentiary Sufficiency: The primary question arising from the complaint as filed is one of evidentiary support: can the Plaintiff amend its pleading or otherwise provide the specific product identifications and infringement contentions (purportedly in the missing Exhibit 2) necessary to move the case forward and define the scope of the dispute?

2. Definitional Scope: A core substantive issue will be one of technological translation: can the claim terms from a 2003-vintage patent, such as "wired telephone network" and "emulating a wired line connection," be construed to cover the architecture of modern cordless phone systems that feature cellular integration, or is there a fundamental mismatch between the claimed technology and the accused products?

3. Claim Viability: The infringement analysis will turn on the viability of the means-plus-function limitations in Claim 1. The central question for the court will be whether the accused products contain structures that are the same as or equivalent to the specific algorithms and hardware configurations disclosed in the '664 patent for performing the claimed functions, such as handling calls and generating tones.