Lenovo United States Inc v. Neodron Ltd

1. Case Identification

• Case #: IPR2020-00729
• Patent #: 8,102,286
• Filed: March 19, 2020
• Petitioner(s): Lenovo (United States) Inc., Dell Technologies Inc., and HP Inc.
• Patent Owner(s): Neodron Ltd.
• Challenged Claims: 1-24

2. Patent Overview

• Title: Capacitive Keyboard with Non-Locking Reduced Keying Ambiguity
• Brief Description: The ’286 patent discloses a method for resolving key-selection ambiguity on capacitive touch keyboards when a user's finger may overlap multiple keys. The system uses a "non-locking" approach where a key selection is biased in favor of the currently active key, preventing undesirable rapid switching (dithering) by requiring a new key's signal to surpass the active key's signal by a select amount before a switch occurs.

3. Grounds for Unpatentability

Ground 1: Claims 1-5, 7-17, and 19-24 are obvious over Jahier in view of Senk.

• Prior Art Relied Upon: Jahier (Patent 5,525,980) and Senk (Patent 5,760,715).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Jahier discloses the core method of the ’286 patent. Jahier teaches a capacitive keyboard with a state machine that preselects a key with the greatest signal strength. It further teaches that a new key can become preselected only if its signal exceeds the currently preselected key's signal by a certain amount (the difference between the preselected key's signal and a "High Threshold"). This establishes the claimed "biasing" in favor of the currently active key. Senk addresses the same multi-touch ambiguity problem and discloses a method of suppressing signals from non-selected keys by temporarily adjusting their reference values, thereby "locking out" other keys to prevent dithering.
  • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine Jahier and Senk as both address the same problem of resolving multi-key touch ambiguity on capacitive keyboards. A POSITA would have been motivated to incorporate Senk’s technique of decreasing the sensor values of inactive keys into Jahier's system to enhance the existing bias. This would create a more stable system, reducing the likelihood of rapid, undesirable switching when multiple keys have similar signal strengths.
  • Expectation of Success: A POSITA would have a reasonable expectation of success in combining these systems, as it involved applying a known technique (Senk’s signal suppression) to improve a known system (Jahier’s key selection logic) for a predictable increase in stability.

Ground 2: Claims 1-5, 7-9, 12-17, 19-20, and 23-24 are obvious over Jahier and Senk in view of QT60161.

• Prior Art Relied Upon: Jahier (Patent 5,525,980), Senk (Patent 5,760,715), and QT60161 (Quantum Research Group 16 Key QMatrix Keypanel Sensor IC Datasheet).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground builds on the combination of Jahier and Senk. Petitioner asserted that QT60161, a datasheet for a commercial capacitive touch controller IC, provides explicit teachings for limitations not fully addressed by Jahier and Senk. Specifically, QT60161 discloses using a "hysteresis" level for deactivating a key, where the signal must cross a different threshold to deactivate than it did to activate (addressing claims 5, 13, 17, 24). It also explicitly discloses a "detection integrator counter" that increments with each sample and requires a condition to persist for a user-defined number of cycles before a key press is confirmed (addressing counter limitations in claims 1-5, 7-9, 12, 14-17, 19-20, 23).
  • Motivation to Combine: A POSITA designing the system of Jahier/Senk would be motivated to use a commercially available controller IC like that described in QT60161 for implementation. Such an IC provides a practical, off-the-shelf solution that incorporates well-known features like hysteresis and integrator counters to improve noise rejection and prevent false detections, directly aligning with the goals of the primary references.

Ground 3: Claims 6 and 18 are obvious over Jahier, Senk, and QT60161 in view of West.

• Prior Art Relied Upon: Jahier (Patent 5,525,980), Senk (Patent 5,760,715), QT60161 (datasheet), and West (Patent 5,831,597).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground adds West to the previous combination to specifically address the "guard ring" limitation recited in dependent claims 6 and 18. West discloses a capacitive touch pad that includes a "guard ring pad" surrounding the sensor pads. The guard ring detects the proximity of a larger object (e.g., a mouse or a user's head) and suppresses the output from the individual sensor pads to prevent erroneous touch indications.
  • Motivation to Combine: A POSITA would be motivated to add the guard ring from West to the keyboard system of the other references to solve the known problem of erroneous inputs caused by unintended proximity. West’s guard ring provides a recognized and effective solution for an additional layer of input validation, which would be a simple and logical improvement to the base system.

4. Key Claim Construction Positions

• "Key": Petitioner proposed construing "key" consistent with the specification's definition as "a touchable portion of a mechanical to electrical transducing device that is non-bistable in nature," specifically excluding conventional mechanical switches.
• "control logic operatively coupled to...": Petitioner argued that this limitation in independent claims 1 and 9 should be construed as a means-plus-function limitation under pre-AIA 35 U.S.C. §112(6). This construction requires identifying corresponding structure in the specification, which Petitioner asserted is a "microprocessor or microcontroller" programmed to execute the logical operations shown in Figures 5A/5B, including using counters. This construction imposes additional structural limitations that Petitioner argued were met by the prior art combinations.

5. Key Technical Contentions (Beyond Claim Construction)

• Priority Date Entitlement: Petitioner contended that the ’286 patent is not entitled to its claimed 2002 priority date. The core inventive concept—the "non-locking" key ambiguity reduction system that operates by "biasing" key selection—was allegedly first disclosed in a provisional application filed on December 21, 2005. Petitioner argued this later date is the proper effective filing date, which is critical for the patentability analysis as it establishes that references like the QT60161 datasheet (published February 2002) qualify as prior art.

6. Relief Requested

• Petitioner requests institution of an inter partes review and cancellation of claims 1-24 of Patent 8,102,286 as unpatentable under 35 U.S.C. §103.