PTAB

IPR2022-01376

Zebra Technologies Corp v. Lone Star SCM Systems Ltd

Log In
Key Events
Petition
petition Intelligence

1. Case Identification

2. Patent Overview

  • Title: Interrogation System and Method
  • Brief Description: The ’717 patent describes an interrogation system for discerning the presence of objects, particularly radio frequency identification (RFID) and metal objects. The system uses an antenna and processing subsystem to detect signals from objects as they move relative to the antenna.

3. Grounds for Unpatentability

Ground 1: Anticipation of Claims 1, 3-4, 8-16, 19, and 20 by Garber

  • Prior Art Relied Upon: Garber (Patent 6,232,870).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Garber, which discloses a handheld RFID device for library inventory management, teaches every limitation of the challenged claims. Garber’s system comprises an antenna and a processor (“control and processing subsystem”) configured to receive signals from multiple RFID tags (“first object and a second object”) simultaneously when they are in close, unobstructed proximity. Garber explicitly teaches identifying multiple items on a library cart in a single pass and notes that tags can be shielded, implying the system works with unshielded tags. The system is also used to identify items as they move through a detection zone relative to the antenna. Dependent claims related to providing object location, user interfaces, communication with external servers, and transmit antennas were also alleged to be disclosed in Garber's detailed description of its handheld device's capabilities.

Ground 2: Obviousness of Claim 2 over Garber in view of Werb

  • Prior Art Relied Upon: Garber (Patent 6,232,870), Werb (WO 01/06401).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground addresses dependent claim 2, which adds a "position sensor" to the system in claim 1 to provide object location. Petitioner asserted that while Garber’s system provides location data based on reading location tags, Werb expressly teaches the use of a position sensor (e.g., GPS or an inertial navigation system) onboard a mobile RFID tag reader. Werb’s system uses data from this sensor to calculate the relative and/or absolute positions of the reader and the tagged assets.
    • Motivation to Combine: Petitioner contended that Garber and Werb are analogous art, both concerning RFID interrogation systems. A person of ordinary skill in the art (POSITA) would combine Werb’s position sensor with Garber’s handheld device to improve item location tracking. Werb explicitly motivates this combination by teaching the use of inertial sensors for indoor environments where GPS is unavailable, such as the library setting described in Garber.
    • Expectation of Success: A POSITA would have a reasonable expectation of success because the components, including RFID readers and inertial sensors, were well-known and their integration to improve location tracking was a predictable application of known technologies.

Ground 3: Obviousness of Claims 6, 7, 17, and 18 over Garber in view of Andersen

  • Prior Art Relied Upon: Garber (Patent 6,232,870), Andersen (Patent 7,151,979).

  • Core Argument for this Ground:

    • Prior Art Mapping: This ground addresses claims requiring specific signal processing techniques, namely "multiscan, coherent signal processing" and an "adaptive integrating filter." Petitioner argued that Andersen teaches using a Kalman filter—a known type of adaptive integrating filter—to process multiple scanned signals from a single object. This technique is used to refine signal data and improve accuracy by mitigating multipath errors, which aligns with the claimed processing limitations.
    • Motivation to Combine: A POSITA would be motivated to incorporate Andersen’s filtering techniques into Garber’s handheld system to enhance detection accuracy. The library environment of Garber, with shelves and other obstacles, is prone to the exact multipath errors that Andersen’s Kalman filter is designed to correct. The combination would predictably improve the performance of Garber’s device.
    • Expectation of Success: Applying a known software filter like a Kalman filter to an RFID system to improve signal quality was a straightforward and well-understood engineering task, leading to a high expectation of success.

  • Additional Grounds: Petitioner asserted additional obviousness challenges based on combinations of Garber, Werb, Andersen, Martinez (Patent 7,039,359), and Arndt (Patent 6,559,645). These grounds were presented as alternatives, contingent on the Board construing certain claim terms as means-plus-function limitations, with Martinez and Arndt providing the requisite structural components for the claimed functions.

4. Key Claim Construction Positions

  • "sensing subsystem configured to...": Petitioner argued this term, recited in claim 3, is a means-plus-function limitation under 35 U.S.C. §112, ¶6 because "subsystem" is a nonce word lacking a sufficiently definite structure.
    • Proposed Function: "providing said first signal and said second signal having a signature representing said first object and said second object, respectively, from said antenna to said control and processing subsystem."
    • Proposed Structure: An "RFID sensing subsystem" and a "metal sensing subsystem," and their equivalents, as described in the ’717 patent specification. This construction was central to Petitioner's arguments, as it required the subsystem to be capable of detecting both RFID and metal signatures.

5. Arguments Regarding Discretionary Denial

  • Petitioner argued that the Board should not discretionarily deny institution under the Fintiv factors. It contended that the parallel district court litigation was in its earliest stages, with no answer filed or invalidity contentions served. Petitioner noted that a pending motion to transfer venue, if granted, would push the trial date to well after the Final Written Decision (FWD) deadline. Furthermore, Petitioner asserted the unpatentability challenges were compelling and relied on prior art references not previously considered by the USPTO, weighing strongly in favor of institution.

6. Relief Requested

  • Petitioner requests institution of inter partes review (IPR) and cancellation of claims 1-4 and 6-20 of the ’717 patent as unpatentable.