PTAB

IPR2015-00534

Biotronik Inc v. Atlas IP LLC

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1. Case Identification

2. Patent Overview

  • Title: Medium Access Control Protocol for Wireless Network
  • Brief Description: The ’734 patent discloses a medium access control (MAC) protocol for managing communications in a wireless network. The protocol uses a central "hub" to establish and control a repeating "communication cycle" with multiple "remotes," transmitting scheduling information that allows the battery-powered remotes to power down their radios when inactive to conserve energy.

3. Grounds for Unpatentability

Ground 1: Anticipation of Claims 6, 14, and 21 over Natarajan 1992

  • Prior Art Relied Upon: Natarajan 1992 (an IEEE P802.11/92-39 working group paper entitled "Medium Access Control Protocol for Wireless LANs (An Update)").
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Natarajan 1992, a publicly distributed paper, discloses every limitation of independent claims 6, 14, and 21. The paper describes a MAC protocol where an "access point" (the claimed hub) coordinates with "mobile units" (the claimed remotes) using a repeating "frame" (the claimed communication cycle). The access point broadcasts headers (AH, BH, CH) containing timing and allocation information, establishing intervals for inbound and outbound traffic. This scheduling information allows remotes to determine precisely when to power on their transmitters and receivers, enabling them to power down at all other times to conserve battery life, thus allegedly meeting all claim elements.

Ground 2: Obviousness of Claim 11 over Natarajan 1992 in view of Bella

  • Prior Art Relied Upon: Natarajan 1992, Bella (Patent 4,542,499).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner asserted that claim 11 differs from the base claims by adding limitations that require the hub to monitor a remote's transmissions and revoke its transmission opportunity if the remote is inactive for a predetermined period. While Natarajan 1992 taught a system with reserved, repeating time slots for isochronous data, cancellation of a reservation required an explicit request from the remote. Bella, which addresses network traffic management, was cited for its explicit teaching of monitoring reserved time slots and automatically cancelling the reservation if the slot goes unused. Petitioner argued this directly supplied the missing limitation.
    • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would have been motivated to combine Bella's simple and efficient automatic cancellation method with Natarajan's protocol to improve network resource management. This combination would be particularly advantageous for the portable remotes in Natarajan's system, which could move out of range and become unable to send an explicit cancellation request.
    • Expectation of Success: The combination involved applying a known technique (automatic cancellation upon inactivity) to a similar system (a scheduled access protocol) to achieve its known function (efficient resource allocation), which would have yielded predictable results.

Ground 3: Obviousness of Claims 6, 14, and 21 over Natarajan ’542 in view of Bantz

  • Prior Art Relied Upon: Natarajan ’542 (Patent 5,241,542), Bantz (Patent 5,123,029).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Natarajan ’542, a patent describing the same work as the Natarajan 1992 paper, discloses a MAC protocol substantially similar to that of the ’734 patent but assumes a fixed base station acting as the hub. The challenged claims, however, recite "designating one of the communicators of the Group as a hub." Bantz was introduced to supply this limitation, as it teaches a protocol for an ad-hoc network of mobile units where one unit is dynamically designated to function as the hub to improve fault tolerance and flexibility.
    • Motivation to Combine: A POSITA would have immediately recognized the relevance of the two patents, as both originated from IBM, related to the same subject matter, and were filed within two months of each other. A POSITA would combine Bantz’s known technique for dynamic hub designation into the Natarajan ’542 system to achieve the well-understood benefits of a more robust and flexible ad-hoc network.
    • Expectation of Success: Given the significant technical overlap and common origin of the references, incorporating the dynamic hub selection feature from Bantz into the MAC protocol of Natarajan ’542 would have been a straightforward design choice with a high expectation of success.
  • Additional Grounds: Petitioner asserted that claim 11 is obvious over the combination of Natarajan ’542 and Bantz, in further view of Bella, essentially combining the logic of Grounds 2 and 3.

4. Key Claim Construction Positions

  • "frame": Petitioner argued this term, as used in the ’734 patent, should be construed as "an ordered group of bits, such as a packet." This construction was critical to distinguish the patent's terminology from the Natarajan prior art, which uses the same term ("frame") to describe what the ’734 patent calls a "communication cycle."
  • "communication cycle": Petitioner proposed construing this term as "a series of intervals for outbound and inbound communications," based on its description and depiction in the ’734 patent specification.

5. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 6, 11, 14, and 21 of the ’734 patent as unpatentable.