Denso Corp v. Netlatch LLC

1. Case Identification

• Case #: IPR2015-00473
• Patent #: 5,530,431
• Filed: December 19, 2014
• Petitioner(s): Denso Corp
• Patent Owner(s): Netlatch LLC (and/or Peter F. Wingard and/or the Bankruptcy Estate of Peter F. Wingard, and/or The Wingard Co.)
• Challenged Claims: 14, 17, 18, 27, 31, and 33

2. Patent Overview

• Title: ANTI-THEFT DEVICE FOR PROTECTING ELECTRONIC EQUIPMENT
• Brief Description: The ’431 patent discloses a method and apparatus for protecting portable electronic equipment (e.g., TVs, VCRs, computers) from theft. The system functions as an electronic "key and lock" where an external "emitter" impresses a unique security code onto the household power line, and a "detector" integrated into the equipment's power supply prevents the equipment from powering up unless it receives the correct code.

3. Grounds for Unpatentability

Ground 1: Anticipation over Simcock - Claims 14, 17, 27, and 31 are anticipated by Simcock under 35 U.S.C. §102(b).

• Prior Art Relied Upon: Simcock (GB 2 229 025).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Simcock, which was not before the Examiner, discloses every limitation of the challenged independent claims. Simcock describes a system for safeguarding electrical apparatus using a transmitter that sends a unique, predetermined, multi-digit security code over the mains power wiring. The transmission occurs "selectively" upon power-up, not continuously. An integrated receiver (the claimed "detector") in the equipment receives the code and enables operation only if the code matches a stored identification number, thus permitting the equipment to be "powered up." Simcock also discloses a portable "power key" in the form of a magnetic card or other data carrier that is insertable into a reader in the transmitter, anticipating the limitations of claim 31.

Ground 2: Obviousness over Simcock in view of Soma - Claims 31 and 33 are obvious over Simcock in view of Soma under 35 U.S.C. §103.

• Prior Art Relied Upon: Simcock (GB 2 229 025) and Soma (Patent 4,734,896).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground asserted that even if Simcock does not explicitly teach every element of claims 31 and 33, the combination with Soma renders them obvious. Soma discloses a burglar-proofing device for a car stereo where a controller card is inserted into a receiving hold in the apparatus. The combination addresses adapting Simcock's transmitter to be directly plugged into the protected equipment, as recited in dependent claim 33.
  • Motivation to Combine: Petitioner contended that a person of ordinary skill in the art (POSITA) would combine Simcock and Soma because they address the same problem of preventing theft of electronic devices. A POSITA would have been motivated to adapt Simcock's power key and transmitter to be insertable directly into the protected equipment, as taught by Soma’s controller card, to create a more integrated and portable security device.
  • Expectation of Success: A POSITA would have had a high expectation of success because the combination involves adapting known, interchangeable electrical components (transmitters, memory, casings) using standard design principles to achieve a predictable result.

Ground 3: Obviousness over Skedung in view of Soma - Claims 14, 17, 18, 27, 31, and 33 are obvious over Skedung in view of Soma under 35 U.S.C. §103.

• Prior Art Relied Upon: Skedung (WO 93/14550) and Soma (Patent 4,734,896).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Skedung teaches a code-protected anti-theft system for electronic appliances with a transmitter and receiver, and Soma provides the missing elements related to a removable power key and plug-in transmitter. Skedung discloses a transmitter that sends an opening code (O-code) over the mains voltage to a receiver integrated into the appliance, which enables power. Skedung's receiver includes a "special rectifier" and "tyristors" (thyristors) for switching power, meeting the "means for switching" limitation of claim 18. Soma's teaching of an insertable controller card with its own memory makes the concept of a removable "power key" (claim 31) and a plug-in transmitter (claim 33) obvious additions to Skedung's system.
  • Motivation to Combine: A POSITA would combine these references to enhance the portability and security of Skedung’s system. Skedung identified the benefit of a portable transmitter, and Soma provided a known method for implementing portability via an insertable card. Furthermore, Soma’s use of volatile memory would have been an obvious solution to prevent a thief from learning the code, a problem inherent in Skedung's design.
  • Expectation of Success: The combination was argued to be a predictable integration of well-known, garden-variety electrical components and memory systems to create a more robust and user-friendly anti-theft device.

4. Key Claim Construction Positions

Petitioner asserted that several claim terms required specific constructions based on the specification and prosecution history, which were central to its unpatentability arguments.

• "selectively" (claim 14): Petitioner argued this term must be construed as "non-continuously." This construction was based on prosecution history estoppel, where the applicant added the term to distinguish over prior art (Bisak) that allegedly transmitted its code continuously.
• "detector" (claim 14) and "emitter" (claim 14): Petitioner argued that the patentee acted as his own lexicographer to distinguish between components operating over household wiring versus wirelessly. A "detector" was defined as a component integrated into the equipment to receive a code over household wiring, and an "emitter" was defined as a component that transmits a code over household wiring. This construction was critical to map the wired power-line communication systems of the prior art.
• "means for switching..." (claim 18): This was construed as a means-plus-function limitation under 35 U.S.C. §112(6). The corresponding structure disclosed in the ’431 patent was identified as the "SCR 324" (a silicon-controlled rectifier, or thyristor) and its equivalents. This specific structural identification allowed Petitioner to map the limitation to the "tyristors" disclosed in the Skedung reference.
• Other means-plus-function terms (claims 14, 17): Petitioner provided detailed constructions for numerous means-plus-function terms (e.g., "transmitter means," "receiver means," "memory means"), identifying specific corresponding structures in the specification, such as "emitter logic and a Code Transmission Circuit" for the "transmitter means."

5. Relief Requested

• Petitioner requested the institution of an inter partes review and the cancellation of claims 14, 17, 18, 27, 31, and 33 of the ’431 patent as unpatentable.