ZTE USA Inc v. Fractus SA

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 Antennae
• Brief Description: The ’069 patent discloses multilevel antennae composed of electromagnetically coupled geometric elements (polygons) that form a larger structure. This design provides multi-band behavior, allowing the antenna to operate in multiple frequency bands while enabling a reduction in overall 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.

• Prior Art Relied Upon: Grangeat (Patent 6,133,879).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Grangeat, which discloses a “multifrequency microstrip antenna” for portable telephones, teaches all limitations of the challenged claims. Specifically, the antenna in Grangeat’s Figure 5 comprises a multilevel structure with multiple conductive zones (the claimed “geometric elements”) that define slots, creating empty spaces. Petitioner asserted, supported by expert simulations, that these slots lengthen current paths, enabling operation in at least three distinct frequency bands. For independent claim 32, Petitioner contended that Grangeat’s antenna has the required "multi-band behavior," with winding current paths that circumvent the empty spaces and common geometric elements traversed by the current at different frequencies. The limitation of being "concealed within a portable communication device" was argued to be an obvious design choice for a small antenna explicitly intended for such devices.
  • Motivation to Combine: This is a single-reference ground based on obviousness. Petitioner argued a person of ordinary skill in the art (POSITA) would be motivated to make minor, obvious modifications to Grangeat's design for its intended purpose. A POSITA would use the small-size antenna internally within a portable device and would modify the disclosed slots to tune performance for known cellular frequency bands as a matter of simple design choice, not invention.
  • Expectation of Success: A POSITA would have a high expectation of success in implementing Grangeat's antenna as an internal, multi-band antenna, as this involves applying known antenna design principles to a structure disclosed for that exact purpose.

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.

• Prior Art Relied Upon: Misra I (IEEE Transactions on Antennas and Propagations, Apr. 1998).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Misra I, which discloses a "concentric microstrip triangular ring antenna" (CMTRA) with a "multiple band effect," renders the claims obvious. The structure in Misra I is inherently multilevel, with the concentric rings forming different levels of detail and the trapezoidal legs of each ring constituting the "geometric elements." These rings define empty spaces that cause current to follow winding paths. Petitioner’s expert simulations allegedly confirmed that the CMTRA operates in at least three frequency bands. Petitioner asserted that Misra I’s disclosure of the antenna’s small size and good radioelectric characteristics would make its incorporation into a portable device a predictable solution for a POSITA.
  • Motivation to Combine: As a single-reference ground, the argument focused on the motivation to adapt Misra I. A POSITA would be motivated to use the Misra I antenna in a portable device to leverage its primary disclosed advantages: increased bandwidth and small size. Petitioner further argued that extending the design from three rings to five to achieve five-band operation would be an obvious and predictable modification for a skilled artisan.
  • Expectation of Success: A POSITA would have a reasonable expectation of success because Misra I provides the fundamental design and teaches using computer simulations (FDTD method) to analyze and optimize its performance, a standard practice in the field.

4. Key Claim Construction Positions

• "antenna element having a multi-band behavior": Petitioner proposed a detailed construction requiring that "most (i.e., more than 75%) of the polygons (polyhedrons) are clearly visible and individually distinguishable and most (i.e., more than 75%) of the polygons (polyhedrons) having an area of contact...that is less than 50% of the perimeter or area." This narrow construction, which distinguished the invention from space-filling or fractal designs, was central to mapping the specific geometric arrangements of Grangeat and Misra I to the claims.
• "not a fractal type antenna": Petitioner argued this term should be construed as "an antenna that does not possess ideal fractal geometry." This construction allowed Petitioner to argue that the geometrically complex prior art antennas fell outside the scope of what the patent disclaimed as "fractal."

5. Key Technical Contentions (Beyond Claim Construction)

• Use of Electromagnetic Simulation: A central technical contention across all grounds was the use of modern electromagnetic simulation software to model the prior art antenna designs described in Grangeat and Misra I. Petitioner argued, via an expert declaration, that these simulations definitively proved the prior art structures inherently possessed the claimed performance characteristics—such as operation at three distinct frequencies with specific impedance levels (VSWR) and radiation patterns—which were not explicitly quantified in the original prior art documents.

6. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under 35 U.S.C. §325(d) would be inappropriate. While Grangeat and Misra I were cited in an Information Disclosure Statement (IDS) during the original prosecution, Petitioner asserted there was no evidence that the examiner substantively considered or applied these references against the claims. The petition also presented new expert testimony and detailed technical simulations that were not before the examiner, creating a new record that warranted the Board's consideration.

7. 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 as unpatentable.