Flex Logix Technologies Inc v. Konda Venkat

1. Case Identification

• Case #: PGR2019-00040
• Patent #: 10,003,553
• Filed: March 18, 2019
• Petitioner(s): Flex Logix Technologies, Inc.
• Patent Owner(s): Konda Technologies Inc.
• Challenged Claims: 1-7, 9-15, and 17-19

2. Patent Overview

• Title: Multi-stage hierarchical network
• Brief Description: The ’553 patent discloses optimized multi-stage switching networks for routing signals between logic blocks on an integrated circuit device, such as a Field-Programmable Gate Array (FPGA). The technology aims to provide efficient layouts that reduce chip area, wire length, and power consumption compared to prior art networks.

3. Grounds for Unpatentability

Ground 1: Claims 1-7, 9-15, and 17-19 are anticipated by Wong under 35 U.S.C. §102(a)(1).

• Prior Art Relied Upon: Wong (Patent 6,940,308).
• Core Argument for this Ground:

  • Prior Art Mapping: Petitioner argued that every limitation of the challenged claims is disclosed in Wong. Wong teaches a programmable Benes network for integrated circuit interconnections, satisfying the preamble limitation of a "network implemented in a non-transitory medium" (e.g., an FPGA). Petitioner asserted that Wong’s network architecture, particularly in Figures 13A and 13B, discloses the claimed "plurality of subnetworks" (rows of switches) arranged in a "two-dimensional grid of rows and columns." Each subnetwork was shown to comprise multiple stages of switches, meeting the claim requirement for y ≥ 1 stages.

  • Petitioner contended that the switches (e.g., switch cells 82 and 83) in Wong’s stages are at least 2x2, thereby having at least two incoming (di ≥ 2) and two outgoing (do ≥ 2) links as required by independent claims 1 and 11. The petition provided a detailed element-by-element analysis showing how Wong’s network includes the claimed inlet links, outlet links, forward connecting links, and backward connecting links. A central part of the argument was that Wong’s embodiments include zero forward or backward "cross links" connecting switches within the same numbered stage. Because the claims require "zero or more" of these same-stage cross links, Petitioner argued that Wong’s disclosure of zero such links meets this optional limitation. The arguments for the dependent claims largely followed this mapping, asserting that since Wong anticipates the independent claims and the dependent claims add only optional or disclosed features, Wong anticipates them as well. For example, claim 9 recites several alternative configurations (e.g., cross links in multiple metal layers, switch size), and Petitioner argued Wong’s disclosure of zero cross links satisfies the first alternative, and its disclosure of 2x2 switches and multiplexers satisfies others.

  • Key Aspects: Petitioner argued that Wong is being presented in a new light. Although Wong was considered during prosecution of the ’553 patent, it was never the basis for a rejection. Petitioner noted that in a related application, the Patent Owner overcame a rejection based on Wong by adding claim limitations that are notably absent from the challenged claims of the ’553 patent.

4. Key Technical Contentions (Beyond Claim Construction)

• Petitioner’s primary technical contention was that the ’553 patent is eligible for Post Grant Review (PGR), a proceeding available only for patents with an effective filing date on or after March 16, 2013. Petitioner argued that multiple challenged claims contain subject matter not disclosed in the pre-AIA priority applications, thus giving them a post-AIA effective filing date.
• Specifically, Petitioner asserted that the term "flip-flop" as a means for configuring a switch (recited in claim 9) was never mentioned in the priority applications. It also argued that the concept of "cross links" connecting switches in the "same numbered stage" of different subnetworks (recited in claim 1) lacked written description support in the earlier filings, which only described cross-links connecting switches in different stages. This alleged introduction of new matter was foundational to establishing the Board’s jurisdiction to institute a PGR.

5. Relief Requested

• Petitioner requests institution of Post Grant Review and cancellation of claims 1-7, 9-15, and 17-19 of the ’553 patent as unpatentable.