HP Inc v. Neodron Ltd

1. Case Identification

• Case #: IPR2020-00459
• Patent #: 8,946,574
• Filed: February 15, 2020
• Petitioner(s): HP Inc., Microsoft Corporation, Dell Inc., Dell Products LP, Lenovo (United States) Inc., and Motorola Mobility LLC.
• Patent Owner(s): Neodron Ltd.
• Challenged Claims: 1-4, 6-11, 13-15

2. Patent Overview

• Title: Two Layer Sensor Stack
• Brief Description: The ’574 patent describes touch sensors for display devices, commonly known as touchscreens. The technology involves a mutual-capacitance sensor configuration with two layers of overlapping electrodes on opposite sides of a substrate, with a key disputed feature being the placement of a second cover sheet between the substrate and the display.

3. Grounds for Unpatentability

Ground 1: Obviousness over Hsu and Mozdzyn - Claims 1-4, 6-11, and 13-15

• Prior Art Relied Upon: Hsu (Patent 7,030,860) and Mozdzyn (Application # 2011/0007011).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Hsu taught a complete multi-layer capacitive touch sensor stack, including a substrate with transparent conductor layers on opposite sides, a first cover sheet, a second cover sheet, and adhesive layers, which could be placed over a display. However, Hsu disclosed electrodes made of materials like Indium Tin Oxide (ITO). Mozdzyn was cited for its teaching of using a conductive metal mesh (e.g., copper, gold) for the electrodes to reduce electrical resistance and improve performance without sacrificing optical quality. Petitioner asserted that substituting Hsu's ITO electrodes with Mozdzyn's metal mesh electrodes would arrive at the claimed invention.
  • Motivation to Combine: A POSITA would combine Hsu and Mozdzyn to gain the benefits taught by Mozdzyn—improved electrical performance and reduced scan times—for the known touchscreen structure disclosed by Hsu.
  • Expectation of Success: A POSITA would have a reasonable expectation of success because both references describe similar capacitive touch screens, and Mozdzyn expressly teaches improving such systems by using metal mesh electrodes.

Ground 2: Obviousness over Hsu and Chang - Claims 1-3, 7-10, and 14-15

• Prior Art Relied Upon: Hsu (Patent 7,030,860) and Chang (Application # 2009/0002337).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground presented a similar argument to Ground 1, with Hsu providing the base touchscreen structure. Chang was introduced as teaching the use of mesh electrodes (a "screen-like shape") to solve the problem of high sheet resistance in conventional ITO-based touch panels, a problem inherent in Hsu’s design. Petitioner contended that Chang’s disclosure of screen-like metal conductors to reduce resistance provided the motivation to modify Hsu’s solid ITO electrodes into the claimed conductive mesh.
  • Motivation to Combine: A POSITA would combine the teachings to overcome the known high-resistance limitations of the ITO electrodes used in Hsu’s system by applying the mesh solution taught by Chang, thereby improving coordinate detection and enabling larger touch panels.
  • Expectation of Success: Success was expected because both Hsu and Chang describe similarly arranged electrodes made of similar materials (ITO, silver, gold), and Chang teaches that its mesh structure can be achieved by simply changing the shape of the electrode using well-known techniques like vapor deposition.

Ground 3: Obviousness over Hsu, Chang, and Frey - Claims 4, 6, 11, and 13

• Prior Art Relied Upon: Hsu (Patent 7,030,860), Chang (Application # 2009/0002337), and Frey (Application # 2009/0219257).

• Core Argument for this Ground:

  • Prior Art Mapping: This ground built upon the combination of Hsu and Chang to address dependent claims reciting specific quantitative limitations. Specifically, claims 4 and 11 require that mesh segments cover approximately 5% of the sensor's active area, and claims 6 and 13 require an optical transmissivity of approximately 90%. While Hsu and Chang provided the mesh electrode structure, Frey was cited for explicitly teaching these precise values. Frey taught that for transparent sensors, an area fraction shadowed by the conductor of less than 5% was desirable and provided an example achieving approximately 91% visible light transmittance.
  • Motivation to Combine: A POSITA, having already combined Hsu and Chang, would consult a reference like Frey to optimize the sensor’s transparency and performance for use with an underlying display. Frey’s teachings on achieving high viewability provided the explicit motivation to select the claimed 5% coverage and 90% transmissivity values.
  • Expectation of Success: The combination was asserted to be a predictable optimization of known design parameters for transparent touch sensors.

• Additional Grounds: Petitioner asserted an additional obviousness challenge against claims 1-4, 6-11, and 13-15 over Hsu in view of Philipp (Application # 2010/0123670). This ground was analogous to Ground 1, arguing for the substitution of Hsu’s ITO electrodes with the fine-line metal mesh electrodes taught by Philipp to improve performance and manufacturing yields.

4. Key Claim Construction Positions

• "cover sheet" (claims 1, 8, 15): Petitioner argued this term was not defined in the specification beyond a "transparent covering sheet" and should be construed broadly as a "sheet that covers something."
• "mesh" (claims 1, 8, 15): Petitioner proposed this term be construed as a "set of wires that surround open spaces in a net or network," consistent with dictionary definitions and the patent's figures.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that the Board should decline to exercise discretionary denial under 35 U.S.C. §325(d) because the petition raised new arguments based on prior art that was not before the examiner during prosecution.
• It was emphasized that none of the primary or secondary references for Grounds 1-3 (Hsu, Mozdzyn, Philipp, Chang) were considered by the examiner. The arguments presented in the petition were therefore substantially different from those previously considered by the PTO.

6. Relief Requested

• Petitioner requested institution of an inter partes review and cancellation of claims 1-4, 6-11, and 13-15 of the ’574 patent as unpatentable.