Microsoft Corp v. Lemko Corp

1. Case Identification

• Case #: IPR2023-00531
• Patent #: 7,855,988
• Filed: February 14, 2023
• Petitioner(s): Microsoft Corporation and Affirmed Networks, Inc.
• Patent Owner(s): Lemko Corporation
• Challenged Claims: 1, 3-9, and 20

2. Patent Overview

• Title: Methods and Devices for Routing Communications Between Distributed Mobile Architecture Servers Using Gateways
• Brief Description: The ’988 patent discloses methods for routing communications between distributed mobile architecture (DMA) gateways. The system is designed to allow a mobile device to maintain communications as it moves from the service area of a first DMA gateway to a second DMA gateway by sharing and storing network information between the gateways.

3. Grounds for Unpatentability

Ground 1: Anticipation of Claims 1, 3-9, and 20 by Flore

• Prior Art Relied Upon: Flore (Application # 2007/0021120).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Flore, which describes handover procedures for user equipment (UE) moving between an E-UTRAN and a legacy UTRAN network, discloses every limitation of the challenged claims. Petitioner mapped the components of Flore’s network to the claimed elements, asserting that a person of ordinary skill in the art (POSA) would understand Flore’s Inter-Access System (Inter-AS) Anchor to be the claimed "first DMA gateway," the Serving GPRS Support Node (SGSN) to be the "second DMA gateway," and the Radio Network Controller (RNC) and Access Gateway (AGW) to be the "DMA servers."
  • Petitioner contended that Flore’s handover process explicitly teaches the core steps of independent claim 1. Specifically, Flore’s Inter-AS Anchor receives communications information (a Packet Data Protocol or PDP context) for a network accessible by the SGSN. This PDP context indicates the UE is accessible by a DMA server (the AGW) and a legacy network (the UTRAN). The Inter-AS Anchor and SGSN participate in a gateway communications network via a Gn interface.
  • Further, Petitioner argued Flore discloses storing this information in a "home DMA register." After the handover, Flore’s Inter-AS Anchor acts as a Gateway GPRS Support Node (GGSN), which inherently includes a location register function. The act of updating the PDP context fields to forward future packets to the SGSN was equated with storing the communications information in this register. Finally, Petitioner asserted Flore discloses receiving a communication for the target device (the UE) at the first gateway (Inter-AS Anchor) and routing it to the second gateway (SGSN) in accordance with the updated PDP context.
  • For the dependent claims, Petitioner argued Flore also discloses the specific types of servers (ground-based, claim 3), communications (voice and data, claim 4), legacy networks (wireless network serviced by an MSC, claim 5), and messaging protocols (notification, automatic sending, and query-response, claims 6-8) recited. For claim 20, Petitioner argued that Flore describes a reverse handover (UTRAN to E-UTRAN) where the first gateway receives information from the second gateway.

4. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under §314(a) is not warranted. Citing the USPTO Director’s interim guidance on parallel proceedings, Petitioner stipulated that, should the Board institute the inter partes review (IPR), it would not pursue the same grounds, or any grounds that could have reasonably been raised, in the parallel district court litigation.

5. Relief Requested

• Petitioner requests institution of an IPR and cancellation of claims 1, 3-9, and 20 of the ’988 patent as unpatentable.