Dell Inc v. Alacritech Inc

1. Case Identification

• Case #: IPR2018-00374
• Patent #: 9,055,104
• Filed: December 27, 2017
• Petitioner(s): Dell Inc.
• Patent Owner(s): Alacritech, Inc.
• Challenged Claims: 1, 6, 9, 12, 15

2. Patent Overview

• Title: Freeing Transmit Memory on a Network Interface Device Prior to Receiving a Remote Acknowledgement
• Brief Description: The ’104 patent discloses a method for offloading transport layer protocol processing, specifically TCP, from a host computer to an intelligent network interface device (NIC). The purported invention is the NIC sending a response to the host indicating that data has been sent to the network before the NIC receives a final delivery acknowledgement (ACK) from the remote device, thereby reducing latency.

3. Grounds for Unpatentability

Ground 1: Obviousness over Connery - Claims 1, 6, 9, 12, and 15 are obvious over Connery in view of the knowledge of a POSA.

• Prior Art Relied Upon: Connery (Patent 5,937,169).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Connery discloses all limitations of the challenged claims. Connery teaches a system that offloads TCP segmentation from a host computer to a "smart adapter" (NIC). This NIC receives a transmit command, segments a large data payload into smaller packets, prepends TCP/IP headers, and transmits the packets. The central inventive concept of the ’104 patent—sending a "data sent" response to the host before receiving a network ACK—was argued to be an obvious implementation of Connery's system. Specifically, Connery teaches that its method reduces host CPU interrupts to "one per 'large packet'" instead of one per packet. Petitioner contended a POSA would understand this single interrupt to be a "transmit completion interrupt," a well-known signal sent from the NIC to the host upon completion of transmission. Due to inherent network latency, this local interrupt would necessarily be sent and received by the host well before the round-trip ACK from the remote device could arrive back at the NIC.
  • Motivation to Combine (with POSA Knowledge): A POSA implementing Connery's system would be motivated to use a transmit completion interrupt for the "one interrupt per large packet" signaling. This approach directly serves Connery's stated goals of reducing host CPU utilization and improving performance by allowing the host to queue the next large data transmission without waiting for a slow network ACK. This was a common and predictable design choice for improving data throughput.
  • Expectation of Success: A POSA would have a high expectation of success in using a transmit completion interrupt. This was a standard, well-understood technique for signaling between hardware (the NIC) and software (the host driver) and was simple to implement in a system like Connery's.

Ground 2: Obviousness over Connery and Boucher - Claims 1, 6, 9, 12, and 15 are obvious over Connery in view of Boucher.

• Prior Art Relied Upon: Connery (Patent 5,937,169), Boucher (WO 00/13091).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground was presented as an alternative to Ground 1, specifically addressing the claim limitation of "maintaining, by the network interface device, a Transport Control Protocol (TCP) connection." Petitioner argued that if Connery were found to not explicitly teach this feature, the combination with Boucher renders it obvious. Boucher discloses an intelligent NIC that offloads TCP/IP processing and explicitly maintains TCP connection state information in a Connection Control Block (CCB) cache. This cache allows the NIC to handle data transfers on an accelerated "fast-path," bypassing the host's protocol stack.
  • Motivation to Combine: A POSA seeking to optimize the performance of Connery's system, especially for bidirectional data flows, would be motivated to incorporate Boucher's teachings. Both references are in the specific field of offloading TCP processing to intelligent NICs. Combining Boucher's explicit connection state management (the CCB cache) with Connery's segmentation offload capabilities would be a natural way to enhance performance and gain the benefit of more efficient bidirectional data flows.
  • Expectation of Success: A POSA would have a high expectation of success in this combination. Integrating a known method for maintaining connection state (Boucher) into a system that already offloads significant TCP functions (Connery) would be a predictable extension of existing technologies to achieve improved performance.

4. Key Claim Construction Positions

• "network interface device": This term was a key issue during the prosecution of the ’104 patent. Petitioner argued that the challenged claims are invalid under both the term's plain and ordinary meaning and under the Board's narrower construction adopted during prosecution. That construction distinguished a peripheral "network interface device of the computer" from an external "gateway." Petitioner asserted that the NIC disclosed in Connery is a peripheral device coupled to the host bus, squarely meeting the Board's narrower construction and distinguishing it from the prior art overcome during prosecution.

5. Arguments Regarding Discretionary Denial

• This petition was filed with a simultaneous motion for joinder to two previously instituted IPRs (IPR2017-01393 and IPR2017-01714) that challenged the same patent on identical grounds. Petitioner's request for joinder served as its primary argument against potential procedural or discretionary denial based on timeliness under §315(b).

6. Relief Requested

• Petitioner requests institution of an inter partes review and cancellation of claims 1, 6, 9, 12, and 15 of Patent 9,055,104 as unpatentable.