ZTE (USA), Inc. v. Fractus, S.A.

1. Case Identification

• Case #: IPR2018-01457
• Patent #: 8,976,069
• Filed: August 3, 2018
• Petitioner(s): ZTE (USA), INC.
• Patent Owner(s): FRACTUS S.A.
• Challenged Claims: 1-3, 9, 15-17, 19-20, 24-25, 27-28, 30-36, 40, 46-48, 50-51, 55-56, 58-59, and 61-62

2. Patent Overview

• Title: Multilevel Antennas
• Brief Description: The ’069 patent relates to compact, multi-band antennas for portable communication devices. The invention uses a "multilevel" structure composed of multiple "geometric elements" (polygons) arranged to create empty spaces, which lengthen current paths to enable operation across multiple frequency bands while maintaining a small antenna size.

3. Grounds for Unpatentability

Ground 1: Obviousness over Grangeat - Claims 1-3, 9, 15-17, 19-20, 24-25, 27-28, 30-36, 40, 46-48, 50-51, 55-56, 58-59, and 61-62 are obvious over Grangeat under 35 U.S.C. §103.

• Prior Art Relied Upon: Grangeat (Patent 6,133,879).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Grangeat teaches a "multifrequency microstrip antenna" for portable telephones that discloses every limitation of the challenged claims. Independent claim 32, for example, requires an internal, multi-band antenna element configured for at least three frequency bands. Grangeat discloses a multi-band antenna for portable phones, and Petitioner asserted it would have been obvious to a person of ordinary skill in the art (POSITA) to use it as an internal antenna. Petitioner’s expert simulations allegedly demonstrated that the Grangeat antenna operates in at least three non-overlapping frequency bands. Further, Grangeat’s structure, comprising multiple radiating "zones" and "slots," was mapped to the ’069 patent's "plurality of geometric elements" that circumvent "empty spaces" to create winding current paths. The shared radiating zones in Grangeat correspond to the claimed feature that the antenna does not comprise separate single-band antennas.
  • Motivation for Obviousness Finding: As a single-reference ground, the motivation was based on the knowledge of a POSITA. Petitioner contended that a POSITA would have found it obvious to adapt the Grangeat antenna for use in a modern portable device. This included making it internal, a common practice for miniaturized antennas, and tuning it to operate in specific, known cellular frequency bands (e.g., 1850-1990 MHz) as a matter of simple design choice. It was also argued that incorporating curved elements to increase bandwidth, as recited in dependent claims, was a well-known technique.
  • Expectation of Success: A POSITA would have a reasonable expectation of success in implementing these modifications. Grangeat explicitly teaches an antenna for portable telephones, and techniques like adjusting slot sizes to tune frequencies are described in the reference, making the outcomes of such modifications predictable.

Ground 2: Obviousness over Misra I - Claims 1-3, 15-17, 27, 30-35, 46-48, 58, and 61-62 are obvious over Misra I under §103.

• Prior Art Relied Upon: Misra I ("Study of Impedance and Radiation Properties of a Concentric Microstrip Triangular ring Antenna...", IEEE Transactions, Apr. 1998).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner asserted that Misra I discloses a compact, multi-band concentric microstrip triangular ring antenna (CMTRA) that anticipates or renders obvious the challenged claims. The concentric triangular rings of the CMTRA were argued to constitute a "multilevel" structure of "geometric elements." Petitioner's simulations of the Misra I antenna allegedly confirmed it operates in at least three frequency bands, with substantially similar impedance and radiation patterns across those bands. The spaces between the concentric rings were identified as the claimed "empty spaces" that create winding current paths. Because Misra I is a microstrip patch antenna, Petitioner argued a POSITA would have known it requires a ground plane to which it is electromagnetically coupled.
  • Motivation for Obviousness Finding: A POSITA would be motivated to use the Misra I antenna in a portable device due to its disclosed advantages of small size and multi-band performance. Petitioner argued it would have been an obvious design choice to implement this antenna inside a portable communication device. Extending the design by adding more concentric rings to operate at five or more frequency bands was presented as a predictable modification that would not require undue experimentation.
  • Expectation of Success: A POSITA would have a high expectation of success because Misra I itself teaches the use of computer simulations (FDTD method) to analyze and model antenna performance, making any design modifications or extensions highly predictable.

4. Key Claim Construction Positions

• "antenna element having a multi-band behavior": Petitioner proposed this key term, used in all claims, be construed as "a structure for an antenna useable at multiple frequency bands with at least two levels of detail...wherein most (i.e., more than 75%) of the polygons...are clearly visible...and most (i.e., more than 75%) of the polygons...having an area of contact...that is less than 50% of the perimeter or area." This narrower construction, incorporating limitations from the specification, was central to Petitioner’s argument, as it then demonstrated how the prior art met these specific quantitative thresholds.
• "not a fractal type antenna": This limitation appears in claims 27, 45, and 58. Petitioner proposed it be construed as "an antenna that does not possess ideal fractal geometry." This construction was argued to be consistent with the ’069 patent’s specification, which states that true "fractal antennas are impossible," allowing Petitioner to argue that the prior art antennas, which are not ideal fractals, meet this limitation.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under §325(d) would be inappropriate. Although the Grangeat and Misra I references were listed in an Information Disclosure Statement (IDS) during prosecution, Petitioner contended that the Examiner never substantively analyzed them or applied them against the claims. The petition was argued to present new arguments, supported by new evidence in the form of expert declarations and detailed technical simulations, that were never before the Patent Office.

6. Relief Requested

• Petitioner requests institution of an inter partes review (IPR) and cancellation of claims 1-3, 9, 15-17, 19-20, 24-25, 27-28, 30-36, 40, 46-48, 50-51, 55-56, 58-59, and 61-62 of the ’069 patent as unpatentable.