DCT

1:25-cv-01481

NetMomentum LLC v. Impinj Inc

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Key Events
Complaint

I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 1:25-cv-01481, D. Del., 12/08/2025
  • Venue Allegations: Venue is asserted based on Defendant's incorporation in Delaware and its maintenance of an established place of business in the district.
  • Core Dispute: Plaintiff alleges that Defendant’s radio-frequency identification (RFID) products infringe a patent related to "semi-transparent" RFID tag antennas designed to be readable when stacked or in close proximity.
  • Technical Context: The technology addresses a key limitation in RFID systems, where tags in a dense configuration can block or interfere with each other, preventing reliable inventory tracking and identification.
  • Key Procedural History: The complaint does not mention any prior litigation, Inter Partes Review (IPR) proceedings, or licensing history related to the patent-in-suit.

Case Timeline

Date Event
2005-05-06 ’726 Patent Application Filing Date
2010-05-11 ’726 Patent Issue Date
2025-12-08 Complaint Filing Date

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

  • Patent Identification: U.S. Patent No. 7,714,726, "Semi-transparent RFID tags," issued May 11, 2010.

The Invention Explained

  • Problem Addressed: The patent's background section describes how conventional RFID tags interact strongly with surrounding radio frequency (RF) fields. When such tags are stacked closely together (e.g., on poker chips, currency, or documents), the outer tags can act as a "Faraday shield," blocking energy from reaching the inner tags and preventing them from being read (Compl. Ex. 1, ’726 Patent, col. 1:26-42).
  • The Patented Solution: The invention is an RF device with a "semi-transparent" antenna. This antenna is designed to gather only some of the incoming RF energy—enough for the tag's circuit to function—while allowing most of the energy to pass through to other tags in a stack. This is achieved by designing an antenna that "minimally affects the electromagnetic RF fields surrounding the antenna" (’726 Patent, Abstract; col. 1:62-col. 2:2). The specification discloses that this can be accomplished using materials with high sheet resistivity and designing the device to have a high total impedance (’726 Patent, col. 3:7-10; col. 5:26-34).
  • Technical Importance: This approach sought to solve what the patent describes as a conventional wisdom that it was "impossible to read a stack of tagged items," thereby enabling reliable RFID tracking in dense storage applications (’726 Patent, col. 1:40-42).

Key Claims at a Glance

  • The complaint alleges infringement of "one or more claims" but does not specify which claims are asserted, instead referring to an unattached exhibit (Compl. ¶11, ¶13). Independent claim 1 is representative of the core invention.
  • Independent Claim 1:
    • A Radio Frequency (RF) device, comprising:
    • a circuit; and
    • an antenna coupled to the circuit,
    • wherein the antenna minimally affects electromagnetic RF fields surrounding the antenna even in the vicinity of the antenna.

III. The Accused Instrumentality

The complaint does not identify any accused products by name. It refers to "Exemplary Defendant Products" that are purportedly identified in claim charts in an "Exhibit 2" (Compl. ¶11, ¶13). However, Exhibit 2 was not filed with the complaint. Consequently, the complaint provides no specific details regarding the functionality, features, or market context of the accused instrumentalities.

IV. Analysis of Infringement Allegations

The complaint references claim charts in an unattached exhibit to support its infringement allegations but does not provide them (Compl. ¶13-14). The narrative infringement theory is limited to the conclusory statement that the "Exemplary Defendant Products practice the technology claimed by the '726 Patent" and "satisfy all elements of the Exemplary '726 Patent Claims" (Compl. ¶13). No probative visual evidence provided in complaint.

  • Identified Points of Contention: Based on the language of the patent and the general nature of the dispute, several points of contention are likely to emerge.
    • Scope Questions: A central dispute may arise over the proper construction of the functional limitation "minimally affects electromagnetic RF fields." The question will be whether this term should be interpreted broadly based on its plain meaning or limited by the specific quantitative examples and physical characteristics disclosed in the patent's specification (e.g., allowing "at least about 50%" of RF energy to pass through, or possessing a specific sheet resistivity).
    • Technical Questions: The infringement analysis will likely depend heavily on technical evidence. A key question will be what type of testing, simulation, or expert analysis is sufficient to prove that an accused antenna meets the functional "minimally affects" limitation. This suggests the case may turn on a battle of experts regarding the RF properties of the accused devices rather than a direct comparison of physical structures.

V. Key Claim Terms for Construction

  • The Term: "minimally affects electromagnetic RF fields" (from Claim 1)
  • Context and Importance: This functional language is the core limitation of the patent's broadest independent claim and distinguishes the invention from the prior art. The outcome of the case will likely hinge on how the court defines the scope of this term.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: Proponents of a broader scope may argue that the term should be given its plain and ordinary meaning, covering any antenna that has a demonstrably small impact on surrounding RF fields, without being tied to a specific structure or mechanism for achieving that result.
    • Evidence for a Narrower Interpretation: The specification provides quantitative context that may support a narrower construction. For instance, it states that "minimally affects" means "at least about 50%, and preferably greater than about 90%, of the RF energy striking the antenna and in the vicinity of the antenna is useable by another RF device" (’726 Patent, col. 5:18-22). The specification also links this functionality to physical properties, such as a sheet resistivity "greater than about 1 Ω/sq" and a total device impedance "greater than about 1000Ω" (’726 Patent, col. 5:27-32).

VI. Other Allegations

  • Indirect Infringement: The complaint contains a single count for "Direct Infringement" and does not allege facts to support claims for either induced or contributory infringement (Compl. p. 2).
  • Willful Infringement: The complaint does not contain allegations of pre-suit knowledge of the ’726 Patent or other facts that would typically support a claim for willful infringement. The prayer for relief requests damages under 35 U.S.C. § 284, which governs enhanced damages, and asks that the case be declared "exceptional" under § 285, but the body of the complaint does not plead a factual basis for willfulness (Compl. p. 4).

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

  1. A core issue will be one of definitional scope: How will the court construe the central functional limitation "minimally affects electromagnetic RF fields"? Will the construction be a qualitative standard, or will it be tied to the quantitative benchmarks (e.g., ">50% energy pass-through, specific sheet resistivity values") disclosed in the patent's specification?
  2. A key evidentiary question will be one of technical proof: As the complaint does not identify accused products or their specific operation, a central question for discovery and trial will be what factual evidence—such as laboratory measurements, RF simulations, or expert testimony—is required to establish that the accused Impinj products in fact meet the functional requirements of the asserted claims.