Encoditech LLC v. ZIH Corp Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Encoditech LLC (Texas)
  • Defendant: ZIH Corp. (Delaware)
  • Plaintiff’s Counsel: Stamoulis & Weinblatt LLC; Rabicoff Law LLC
• Case Identification: 1:19-cv-01443, D. Del., 07/31/2019
• Venue Allegations: Plaintiff alleges venue is proper in the District of Delaware because Defendant ZIH Corp. is a Delaware corporation and has allegedly committed acts of patent infringement in the district.
• Core Dispute: Plaintiff alleges that Defendant’s Zebra-brand ultra-rugged scanners infringe a patent related to establishing direct, secure wireless communications between mobile devices.
• Technical Context: The technology concerns infrastructure-less digital communication protocols, enabling devices to connect directly without relying on a central network like a cellular system.
• Key Procedural History: The complaint notes that a certificate of correction for the asserted patent was filed on May 23, 2017. This correction materially amended the scope of at least one asserted claim, which will be a central factor in claim construction and infringement analysis.

Case Timeline

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

U.S. Patent No. 6,321,095, "Wireless Communications Approach," issued Nov. 20, 2001

The Invention Explained

• Problem Addressed: The patent identifies drawbacks in then-existing wireless technologies. Traditional two-way radios are described as often lacking privacy and operating in a half-duplex mode (only one person can talk at a time), while digital cellular systems require costly infrastructure and are often unavailable in remote locations (’095 Patent, col. 1:22-49, col. 2:1-5).
• The Patented Solution: The invention proposes a system for mobile stations to establish a direct, digital communication link without needing intermediary base stations (’095 Patent, Abstract). The system uses a composite protocol (e.g., FDMA/TDMA) where one device can act as a "pseudo base station" (PBS) for a given session, managing the allocation of communication slots and enabling secure, multi-participant conversations (’095 Patent, col. 2:30-41; col. 6:54-67). This approach aims to combine the free-roaming mobility of two-way radios with the security and advanced features of digital cellular service (’095 Patent, col. 4:56-62).
• Technical Importance: The described technology provides a framework for secure, ad-hoc wireless networks, which is valuable for applications where dedicated infrastructure is impractical or unavailable, such as in logistics, public safety, or remote industrial environments (’095 Patent, col. 1:17-21).

Key Claims at a Glance

• The complaint asserts "at least exemplary claim 7" (’095 Patent, Compl. ¶17).
• A Certificate of Correction filed in 2017 effectively rewrote claim 7, converting it into a self-contained independent claim. The essential elements of the corrected claim 7 are:
  • A wireless communication system comprising a first mobile station and a second mobile station.
  • The first mobile station is configured to:
    • select a portion of an RF band for communication.
    • transmit a request signal directly to the second mobile station.
    • establish a direct communication link in response to receiving an acknowledge signal.
    • receive a public encryption key from the second mobile station.
    • generate a message containing a common encryption key (Ckey).
    • encrypt that message using the public key and provide it to the second mobile station for decryption to extract the Ckey.
  • Messages exchanged thereafter are encrypted using the Ckey.
  • The second mobile station is configured to transmit the acknowledge signal in response to the first request signal.
• The complaint does not explicitly reserve the right to assert dependent claims.

III. The Accused Instrumentality

Product Identification

• The complaint identifies "at least the Zebra DS3608-ER/DS3678-ER Ultra-Rugged Scanner" as the "Exemplary ZIH Products" (Compl. ¶17).

Functionality and Market Context

• The complaint does not provide specific details on the technical operation of the accused scanners (Compl. ¶17). It alleges generally that these products are made, used, sold, and imported by the Defendant and are used internally by Defendant's employees (Compl. ¶17-18). The complaint does not describe the products' commercial importance or market position.

No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

The complaint references claim charts in an "Exhibit 3" that was not provided with the filing; therefore, a claim chart summary cannot be created (Compl. ¶21-22). The infringement theory is presented in conclusory terms, stating that the accused products "practice the technology claimed" and "satisfy all elements" of the asserted claims (Compl. ¶21). The core of the allegation is that the accused Zebra scanners directly infringe claim 7 by establishing direct, secure wireless communications.

• Identified Points of Contention:
  • Scope Questions: A primary question will be whether the term "mobile station", as defined and used in the patent, can be construed to read on an industrial barcode scanner system. The patent’s background and description focus heavily on voice communication devices like handsets and two-way radios, which may create a dispute over the intended scope of the claims (’095 Patent, col. 1:22-29, col. 4:1-3).
  • Technical Questions: The asserted claim 7 recites a highly specific, multi-step method for establishing a secure channel using a public/private key exchange to share a separate "common encryption key (Ckey)" for ongoing communication (’095 Patent, col. 23:1-24:24, as corrected). A central evidentiary issue will be whether the accused scanners perform this exact cryptographic protocol. The complaint does not provide any factual allegations to support that the accused products perform this specific function.

V. Key Claim Terms for Construction

• The Term: "mobile station"

• Context and Importance: The applicability of the patent to the accused scanners hinges on the scope of this term. Defendant may argue the term is limited to the voice-centric devices discussed in the specification, while Plaintiff will likely advocate for a broader definition covering any mobile wireless device. Practitioners may focus on this term because its construction could be dispositive of infringement.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The specification provides an exemplary, non-limiting definition: "the term 'mobile station' refers to a mobile communication device, for example a handset" (’095 Patent, col. 4:1-3). The use of "for example" may support a construction that is not limited to voice handsets.
  • Evidence for a Narrower Interpretation: The "Background of the Invention" section exclusively discusses "two-way radios and cellular telephone systems" for voice communication, potentially suggesting the problem being solved and the invention itself were conceived of in this narrower context (’095 Patent, col. 1:22-24).

• The Term: "direct communication link"

• Context and Importance: This term is critical for determining whether the architecture of the accused scanner system infringes. The dispute may center on whether communication routed through a local base station or cradle, but not a public carrier network, qualifies as "direct."

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The patent repeatedly contrasts its "direct" approach with systems requiring the "physical infrastructure of digital cellular telephone systems," which consist of a network of base stations covering a wide area (’095 Patent, col. 4:59-62). This could support a reading where any communication not traversing a wide-area cellular network is "direct."
  • Evidence for a Narrower Interpretation: The patent’s abstract describes establishing "a direct, digital communication link between mobile stations," and Figure 1 depicts link 106 connecting two mobile stations with no intermediary hardware shown (’095 Patent, Abstract; Fig. 1). This could support a narrower construction requiring a true peer-to-peer connection.

VI. Other Allegations

• Willful Infringement: The complaint alleges that the filing of the lawsuit itself provides Defendant with "notice and actual knowledge" of the patent (’095 Patent, Compl. ¶19). It further alleges that any continued infringing activity by the Defendant after this date is willful (’095 Patent, Compl. ¶20). The complaint does not allege any pre-suit knowledge on the part of the Defendant.

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

• A core issue will be one of definitional scope: can the term "mobile station", which is described in the patent primarily in the context of voice-centric handsets, be construed to cover the accused industrial scanner system? The outcome of this claim construction dispute could determine the applicability of the patent to the accused technology.
• The case will also present a key evidentiary question of operational function: the complaint makes conclusory allegations of infringement without providing technical details. A central issue for the court will be whether discovery produces evidence that the accused scanners actually perform the highly specific, multi-step cryptographic protocol for establishing a shared common key, as explicitly required by the corrected version of asserted claim 7.