Apple Inc v. Neodron Ltd

1. Case Identification

• Case #: IPR2020-00778
• Patent #: 7,821,425
• Filed: April 16, 2020
• Petitioner(s): Apple Inc. and Microsoft Corporation
• Patent Owner(s): Neodron, Ltd.
• Challenged Claims: 1-40

2. Patent Overview

• Title: Methods and Devices for Non-Locking Key Ambiguity Reduction
• Brief Description: The ’425 patent describes methods and devices for reducing keying ambiguity on capacitive touch surfaces. The system selects a user-intended key based on comparative signal strengths and employs a "non-locking" approach that biases the determination in favor of a currently selected key to prevent undesirable rapid switching ("dithering") as a user's finger moves across keys.

3. Grounds for Unpatentability

Ground 1: Claims 1-2, 5-10, 14-19, 24-25, 29-37, and 39-40 are obvious over Jahier in view of the knowledge of a POSITA.

• Prior Art Relied Upon: Jahier (Patent 5,525,980)
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Jahier teaches the core limitations of the ’425 patent. Jahier discloses a capacitive keyboard that cyclically measures capacitance to determine key selection. To manage conflicts when multiple keys are activated, Jahier's controller preselects the key with the greatest signal difference above a low threshold. On subsequent cycles, a second key can only displace the preselected key if its signal exceeds both the preselected key's signal and a separate high threshold. Petitioner asserted this two-threshold system constitutes the "biasing" of the comparison in favor of the previously selected key, as recited in independent claims 1, 7, 16, 25, and 33.
  • Motivation to Combine (for §103 grounds): The combination is with the general knowledge of a POSITA. Petitioner contended that Jahier is analogous art as it is in the same field of endeavor (capacitive input devices) and solves the same problem (ambiguity in key selection). Any minor differences, such as implementing hysteresis or counters, were argued to be within the routine knowledge of a POSITA to solve known instability issues.
  • Expectation of Success: A POSITA would have an expectation of success in applying Jahier’s teachings because it directly addresses the same problems of ambiguity and conflict resolution in capacitive keyboards.

Ground 2: Claims 5, 14, 23, 26-28, 30, and 36 are obvious over Jahier in view of QT60161.

• Prior Art Relied Upon: Jahier (Patent 5,525,980) and QT60161 (a Quantum Research Group datasheet).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground built upon the teachings of Jahier and added QT60161 to address claims requiring counters and hysteresis. QT60161, a datasheet for a capacitive keypad sensor IC, explicitly discloses a "detection integrator" counter associated with each key. This counter increments with each detection sample until a user-defined limit is reached to confirm a touch, thereby filtering noise. QT60161 also teaches programmable hysteresis levels to prevent output chatter when a signal hovers near the detection threshold.
  • Motivation to Combine: A POSITA would combine the teachings of QT60161 with Jahier's system to improve its robustness. Petitioner argued that adding a detection integrator counter and a distinct hysteresis level are well-known techniques to suppress false detections from environmental noise and increase measurement reliability, which are stated goals of QT60161.
  • Expectation of Success: A POSITA would have a reasonable expectation of success because implementing these features would involve minor, well-understood software modifications to employ a known concept (detection integration) into Jahier's existing comparative measurement system.

Ground 3: Claims 4, 12-13, and 21-22 are obvious over Jahier in view of Houston.

• Prior Art Relied Upon: Jahier (Patent 5,525,980) and Houston (Patent 6,696,985).

• Core Argument for this Ground:

  • Prior Art Mapping: This ground addressed claims reciting specific methods of biasing, such as increasing the signal strength of the selected key or decreasing the signal strength of other keys. While Jahier provided the foundational biased comparison, Houston was cited for its explicit teaching of a weighting algorithm for a capacitive keyboard. Houston assigns greater weight to signals in the center of a contact pattern and less weight to peripheral signals to resolve ambiguity.
  • Motivation to Combine: Petitioner argued a POSITA would be motivated to apply Houston's weighting algorithm to Jahier's system to predictably enhance the bias effect. Applying a "greater weight" (i.e., increasing the signal strength) to the preselected key, or a "lesser weight" (decreasing signal strength) to other keys, are two sides of the same coin to achieve a more robust bias, which is the exact problem Houston addresses.
  • Expectation of Success: Success would be expected as it would require a skilled artisan to apply simple, known software modifications (a weighting algorithm) to the selection controller to enhance an existing function.

• Additional Grounds: Petitioner asserted an additional challenge to claims 4, 12-13, and 21-22 based on Jahier in view of Senk (Patent 5,760,715), which taught adjusting a key's threshold value to effectively change its signal value. Petitioner also challenged claims 3, 11, 20, and 38 as obvious over Jahier in view of West (Patent 5,831,597), arguing West’s teaching of a "guard ring" to prevent erroneous touch indications would have been an obvious feature to add to Jahier’s keyboard.

4. Key Claim Construction Positions

• "Key": Petitioner noted that in a prior related investigation, the parties agreed that "key" means "a touchable portion of a mechanical to electrical transducing device that is nonbistable in nature," specifically excluding conventional mechanical switches. Petitioner argued that Jahier's capacitive sensors meet this construction.
• "Controller": For claims 1, 25, and 33, Petitioner anticipated a means-plus-function interpretation under §112(6). Petitioner argued that even under such a construction, the controller combination disclosed in Jahier (selection controller, validation controller, and decoding logic) is structurally equivalent to the microprocessor/microcontroller structure disclosed in the ’425 patent for performing the recited biasing functions.

5. Key Technical Contentions (Beyond Claim Construction)

• Priority Date Entitlement: Petitioner dedicated significant argument to establishing that the ’425 patent is not entitled to its claimed 2002 priority date. It was argued that the core "non-locking" and "biasing" concepts, which are recited in every independent claim, were new matter first introduced in a provisional application filed on December 21, 2005. This later priority date is critical as it makes several key prior art references, including QT60161, available under §102(b).

6. Relief Requested

• Petitioner requests the institution of an inter partes review and the cancellation of claims 1-40 of the ’425 patent as unpatentable.