Wifidelity LLC v. Navigine Corp

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: WiFidelity LLC (New Mexico)
  • Defendant: Navigine Corporation (Germany)
  • Plaintiff’s Counsel: Rabicoff Law LLC
• Case Identification: 2:25-cv-01140, E.D. Tex., 11/19/2025
• Venue Allegations: Venue is alleged to be proper because the Defendant is a foreign corporation and has allegedly committed acts of patent infringement in the district.
• Core Dispute: Plaintiff alleges that Defendant infringes a patent related to systems and methods for precisely locating and tracking wireless terminals within a defined three-dimensional space.
• Technical Context: The technology at issue enables high-precision indoor positioning by using an array of receivers to calculate a wireless device's location based on signal time-of-arrival, a key capability for indoor navigation, asset tracking, and location-based services.
• Key Procedural History: The complaint does not reference any prior litigation, licensing history, or other significant procedural events.

Case Timeline

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

U.S. Patent No. 9,002,376 - Systems and methods for gathering information about discrete wireless terminals

• Patent Identification: U.S. Patent No. 9,002,376, "Systems and methods for gathering information about discrete wireless terminals," issued April 7, 2015.

The Invention Explained

• Problem Addressed: The patent describes the limitations of prior art methods for locating wireless devices and controlling their use in specific areas (’376 Patent, col. 1:21-col. 2:65). Existing radio direction finding was imprecise, especially indoors where multipath signal reflections cause errors, and signal-strength boundaries were poorly defined (’376 Patent, col. 1:36-44, 48-52). Furthermore, attempts to create "quiet zones" in places like theaters were either ineffective (asking users to turn off devices) or illegal ("jamming" devices) (’376 Patent, col. 2:39-56).
• The Patented Solution: The invention proposes a system using an array of four or more synchronized receivers that define a three-dimensional volume, termed a "defined local space" or "DLS" (’376 Patent, col. 6:35-49). When a wireless terminal (e.g., a cell phone) transmits a signal within this space, each receiver records the signal's arrival time (’376 Patent, col. 6:50-55). A central processor then uses these relative time of arrival (RTOA) measurements to calculate the terminal's precise physical location within the DLS, allowing for accurate tracking and the creation of virtual boundaries for monitoring or control (’376 Patent, Abstract; col. 6:30-35). This process is illustrated in figures such as Fig. 2a, which shows receivers (160) defining a DLS (150) and detecting signals (140) from terminals (130) to determine their position.
• Technical Importance: This approach provided a method for passive, high-precision tracking of standard wireless devices in complex environments like building interiors, without requiring special hardware on the devices themselves.

Key Claims at a Glance

The complaint does not specify which claims are asserted, instead referring to "Exemplary '376 Patent Claims" identified in an unprovided Exhibit 2 (Compl. ¶11). For the purpose of analysis, independent claim 1 is representative:

• determining positioning of a plurality of receivers capturing a first wireless signal emitted from the wireless terminal;
• determining a plurality of defined local spaces (DLSs), each DLS defining a volume among four receivers of the plurality of receivers;
• determining a plurality of points within each DLS, including spatially relating each point to the positioning of the four receivers defining the corresponding DLS;
• determining a four travel times for each point, each travel time representing time needed for wireless signals to travel from the corresponding point to a corresponding one of the four receivers defining the corresponding DLS;
• determining a first plurality of first arrival times, each first arrival time representing time for the first wireless signal to reach each of the plurality of receivers;
• determining the wireless terminal to be positioned within a first DLS of the plurality of DLSs, the first DLS being associated with the point having travel times most closely correlated with the first arrival times.
  (’376 Patent, col. 13:21-44). The complaint does not explicitly reserve the right to assert dependent claims but refers generally to "one or more claims" (Compl. ¶11).

III. The Accused Instrumentality

Product Identification

The complaint does not name any specific accused products or services (Compl. ¶11). It refers to them as "Exemplary Defendant Products" and states they are identified in charts incorporated by reference as Exhibit 2, which was not provided with the complaint (Compl. ¶11, ¶16).

Functionality and Market Context

The complaint does not provide sufficient detail for analysis of the accused instrumentality's functionality. It makes a conclusory allegation that the products "practice the technology claimed by the '376 Patent" and "satisfy all elements" of the exemplary claims, again deferring all technical details to the unprovided Exhibit 2 (Compl. ¶16).

IV. Analysis of Infringement Allegations

The complaint’s infringement allegations are made by incorporating by reference claim charts contained in an unprovided Exhibit 2 (Compl. ¶16, ¶17). The body of the complaint does not contain a narrative infringement theory or map any specific product features to the patent’s claim elements. Therefore, a claim chart summary cannot be constructed from the provided documents.

No probative visual evidence provided in complaint.

Identified Points of Contention

Based on the technology of the ’376 Patent and the general nature of the allegations, the dispute may focus on the following questions:

• Scope Questions: How does the accused system's location-determination algorithm function? The patent claims a specific method of defining "points" within a DLS, calculating theoretical "travel times" for each point, and identifying the point whose travel times are "most closely correlated" with the measured arrival times. A key question will be whether the accused system's algorithm falls within this claimed method or uses a mathematically distinct approach to multilateration.
• Technical Questions: What is the "first wireless signal" captured and used for location by the accused system? The patent specification contemplates intercepting administrative signals transmitted between a device and a cellular network (’376 Patent, col. 4:51-54, col. 5:16-23). The infringement analysis may turn on whether the accused system uses these types of signals or relies on other signals, such as Wi-Fi or Bluetooth transmissions, and whether such signals meet the claim limitations.

V. Key Claim Terms for Construction

"defined local spaces (DLSs)"

• Context and Importance: This term is foundational to the patent, defining the environment in which the invention operates. Its construction will determine the scope of physical spaces covered by the claims.
  • Intrinsic Evidence for a Broader Interpretation: The claim language itself defines a DLS as a "volume among four receivers," which could support a broad, purely geometric interpretation not tied to a specific purpose (’376 Patent, col. 13:27-28).
  • Intrinsic Evidence for a Narrower Interpretation: The specification provides numerous examples of DLSs tailored to specific applications, such as retail store zones, aircraft cabins, and the area around a driver's seat (’376 Patent, Figs. 15, 21, 23). This may support an interpretation that a DLS must be a space defined for a particular monitoring or control function.

"point having travel times most closely correlated with the first arrival times"

• Context and Importance: This phrase describes the core of the claimed location-calculation algorithm. Whether the accused system's method is covered by this language will be a central issue of infringement. Practitioners may focus on this term because a narrow construction could enable a defendant to design a non-infringing alternative algorithm.
  • Intrinsic Evidence for a Broader Interpretation: A party could argue this language should be read broadly to encompass any algorithm that finds the best fit between measured time-of-arrival data and a physical model of the space, regardless of the specific mathematical technique.
  • Intrinsic Evidence for a Narrower Interpretation: The language suggests a discrete, multi-step process: (1) defining a plurality of "points" in a space, (2) calculating theoretical "travel times" for each, and (3) performing a "correlation." A party could argue this does not read on algorithms that solve for position more directly, for example, by calculating the intersection of hyperboloids without a discrete "correlation" step against pre-defined points.

VI. Other Allegations

Indirect Infringement

The complaint alleges induced infringement, stating that the Defendant distributes "product literature and website materials" that instruct end users on how to use its products in a manner that infringes the ’376 Patent (Compl. ¶14). The complaint references an unprovided Exhibit 2 for the content of these materials (Compl. ¶14).

Willful Infringement

While the complaint does not use the word "willful," it alleges that the Defendant obtained "actual knowledge" of its infringement upon service of the complaint and associated claim charts (Compl. ¶13). It further alleges that despite this knowledge, the Defendant has continued its infringing activities (Compl. ¶14). This forms a basis for post-suit willful infringement.

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

• A core issue will be one of algorithmic scope: does the asserted patent claim a specific method of calculating location by correlating measured times against a grid of pre-defined "points," or can the claims be construed to cover a broader class of multilateration algorithms that may be used in the accused system?
• A key evidentiary question will be one of technical implementation: what specific wireless signals does the accused system rely on for positioning (e.g., cellular, Wi-Fi, Bluetooth), and does the system's architecture, including its receivers and processor, operate in a manner that meets the structural and functional limitations of the asserted claims?
• A critical procedural issue in the case's early stages will be the sufficiency of the complaint itself, which defers all substantive factual allegations regarding the identity and operation of the accused products, as well as the theory of infringement, to an unprovided external exhibit.