DCT

4:24-cv-00623

Morris Routing Tech LLC v. AT&T Inc

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 4:24-cv-00623, E.D. Tex., 10/04/2024
  • Venue Allegations: Plaintiff alleges venue is proper because AT&T maintains regular and established places of business within the Eastern District of Texas, including numerous retail stores and innovation centers, and has committed acts of infringement in the district.
  • Core Dispute: Plaintiff alleges that Defendant’s telecommunications networks, which utilize Segment Routing technology, infringe eight patents related to methods for routing data packets.
  • Technical Context: The dispute centers on Segment Routing (SR), a network traffic engineering technology that aims to simplify network architecture and improve efficiency by encoding routing paths within the data packets themselves, a feature of significant importance in 5G and modern IP networks.
  • Key Procedural History: The action was initiated via a First Amended Complaint, which added U.S. Patent No. 12,058,042 after its issuance on August 6, 2024. The complaint also references prior, separate litigation against AT&T to support its venue contentions.

Case Timeline

Date Event
2012-10-05 Earliest Priority Date for all Patents-in-Suit
2019-08-27 U.S. Patent No. 10,397,101 Issues
2019-09-10 U.S. Patent No. 10,411,998 Issues
2019-10-15 U.S. Patent No. 10,447,575 Issues
2019-11-12 U.S. Patent No. 10,476,787 Issues
2019-12-03 U.S. Patent No. 10,498,642 Issues
2020-08-25 U.S. Patent No. 10,757,020 Issues
2020-09-01 U.S. Patent No. 10,764,171 Issues
2024-08-06 U.S. Patent No. 12058042 Issues
2024-10-04 First Amended Complaint Filed

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 10,397,101 - "Routing Methods, Systems, and Computer Program Products for Mapping Identifiers"

The Invention Explained

  • Problem Addressed: The patent’s background section describes challenges in network addressing stemming from the internet’s growth, which created problems of scalability and latency under traditional routing protocols that distinguished strictly between names, addresses, and routes (’101 Patent, col. 1:54–2:44). Traditional IP/MPLS networks required intermediate routers to maintain extensive state information for every data flow, creating scalability issues (Compl. ¶25).
  • The Patented Solution: The invention proposes a path-based routing method where network path information is carried in the header of a data packet, such as one using the Multiprotocol Label Switching (MPLS) protocol (’101 Patent, Abstract). A key aspect is the use of identifiers in a "scope-specific" identifier space; a current node in the path can use an identifier specific to a previous node to determine the next hop, effectively mapping identifiers from one node's context to another's to continue the data transmission without requiring each node to maintain global path state (’101 Patent, Abstract; col. 3:1-18).
  • Technical Importance: This source-routing approach reduces the per-flow state that must be maintained in network nodes, aiming to simplify network architecture and improve scalability and flexibility (Compl. ¶27).

Key Claims at a Glance

  • The complaint asserts at least independent claim 1 (Compl. ¶75).
  • Claim 1 of the ’101 Patent requires a method at a current node in a network that involves:
    • Receiving, from a previous node, network path information in a packet header (specified according to an MPLS protocol).
    • The path information is received based on an identifier in an identifier space that spans within the previous node.
    • This identifier identifies a particular network interface, node, or region.
    • The identifier includes a sequence of identifiers, where the last identifier is configured for use in identifying a "scope-specific identifier" that is specific to another node.
    • Performing an operation to identify a "current identifier" in another identifier space that spans within the current node.
    • Transmitting the data based on this "current identifier."
  • The complaint reserves the right to assert additional claims (Compl. ¶76).

U.S. Patent No. 10,411,998 - "Node Scope-Specific Outside-Scope Identifier-Equipped Routing Methods, Systems, and Computer Program Products"

The Invention Explained

  • Problem Addressed: The patent addresses the same general problems of network scaling and routing complexity as the ’101 Patent, stemming from the limitations of traditional IP addressing schemes (’998 Patent, col. 1:12–2:50).
  • The Patented Solution: This patent refines the path-based routing concept by introducing a "node scope-specific outside-scope identifier." This is an identifier that is specific to the current node but identifies a first region of the network that is outside the node's immediate scope (’998 Patent, Abstract). A packet containing this identifier is transmitted along a first path segment to a path node in that outside region. This allows a node to efficiently direct traffic toward a remote region or network segment without needing to know the granular path details within that region (’998 Patent, Abstract; col. 31:40-54).
  • Technical Importance: This technique facilitates efficient routing across different network segments or domains, which is a foundational element of large-scale traffic engineering and technologies like network slicing (Compl. ¶36).

Key Claims at a Glance

  • The complaint asserts at least independent claim 1 (Compl. ¶83).
  • Claim 1 of the ’998 Patent requires a method at a current node that includes:
    • Receiving an indication of a receipt of a first packet (IP protocol).
    • Identifying, from the packet header, network path information that includes a "node scope-specific outside-scope identifier."
    • This identifier is in an identifier space specific to the current node, does not include a network interface identifier portion, and identifies a first region of the network.
    • The network path includes a first path segment coupling the current node and the first region, and a second path segment in a second region.
    • Causing transmission of data based on this identifier along with at least one of the path segment identifiers.
  • The complaint reserves the right to assert additional claims (Compl. ¶84).

U.S. Patent No. 10,447,575 - "Routing Methods, Systems, and Computer Program Products"

  • Technology Synopsis: This patent describes routing methods using path-based protocol addresses. The technology allows a node to receive a packet containing an outside-scope identifier and, based on that identifier, select a path from a plurality of available multi-hop path segments to forward the packet toward the identified region (’575 Patent, Abstract).
  • Asserted Claims: At least independent claim 1 (Compl. ¶90).
  • Accused Features: AT&T Networks supporting Segment Routing (Compl. ¶¶ 67-70, 90).

U.S. Patent No. 10,476,787 - "Routing Methods, Systems, and Computer Program Products"

  • Technology Synopsis: This patent discloses a routing method using a "region scoped node identifier." This identifier, which has a scope spanning a particular region of a network, globally identifies a particular node within that region, allowing for efficient routing to specific nodes within defined network areas (’787 Patent, Abstract).
  • Asserted Claims: At least independent claim 1 (Compl. ¶98).
  • Accused Features: AT&T Networks supporting Segment Routing (Compl. ¶¶ 67-70, 98).

U.S. Patent No. 10,498,642 - "Routing Methods, Systems, and Computer Program Products"

  • Technology Synopsis: This patent describes a system for constraining data routing based on a policy. A topology node identifies first and second sequences of identifiers for routing between nodes and combines them into a third sequence that reflects the policy, which is then used to constrain the data path (’642 Patent, Abstract).
  • Asserted Claims: At least independent claim 1 (Compl. ¶106).
  • Accused Features: AT&T Networks supporting Segment Routing (Compl. ¶¶ 67-70, 106).

U.S. Patent No. 10,757,020 - "Routing Methods, Systems, and Computer Program Products"

  • Technology Synopsis: This patent discloses a method for routing data from a source node to a destination node using a "source-destination protocol address" that is identified in a scope-specific address space of the source region. This allows a source node to specify a destination node that is not in its local region using a locally scoped address (’020 Patent, Abstract).
  • Asserted Claims: At least independent claim 1 (Compl. ¶114).
  • Accused Features: AT&T Networks supporting Segment Routing (Compl. ¶¶ 67-70, 114).

U.S. Patent No. 10,764,171 - "Routing Methods, Systems, and Computer Program Products"

  • Technology Synopsis: This patent describes a method for using path segment identifiers to route a packet. An active identifier indicator in the packet header designates which segment identifier is for use by the current node; upon processing, the indicator is updated to designate the next segment identifier for the subsequent node, allowing the packet to traverse a pre-defined path (’171 Patent, Abstract).
  • Asserted Claims: At least independent claim 1 (Compl. ¶121).
  • Accused Features: AT&T Networks supporting Segment Routing (Compl. ¶¶ 67-70, 121).

U.S. Patent No. 12,058,042 - "Routing Methods, Systems, and Computer Program Products"

  • Technology Synopsis: This patent is directed to a method for constraining data routing using a policy determined by a topology node. It is substantially similar in its core technical disclosure to the ’642 Patent (’042 Patent, Abstract).
  • Asserted Claims: At least independent claim 1 (Compl. ¶129).
  • Accused Features: AT&T Networks supporting Segment Routing (Compl. ¶¶ 67-70, 129).

III. The Accused Instrumentality

  • Product Identification: The accused instrumentalities are AT&T’s networks, including its fixed-line, fiber, IP, wireless, and Public Safety networks, which are operated under brands including "AT&T," "FirstNet," and "Cricket Wireless" (Compl. ¶65). Specifically, the complaint targets the aspects of these networks that support Segment Routing (SR), including SR-MPLS and SRv6, and comply with the functionality specified in various Internet Engineering Task Force (IETF) standards known as SR RFCs (Compl. ¶¶67-70).
  • Functionality and Market Context: The complaint alleges that AT&T's networks utilize virtualized (NFV) and disaggregated functionalities, relying on infrastructure components from vendors such as Ericsson, Ribbon, Nokia, and Samsung to support SR and the SR RFCs (Compl. ¶66). The complaint highlights AT&T's advertising of its 5G wireless network coverage in the Eastern District of Texas, a key market for SR-based technologies. The complaint provides a screenshot of AT&T's wireless coverage map for Marshall, Texas, to illustrate the availability of its 5G and 4G LTE services in the district (Compl. p. 5). It also alleges AT&T operates numerous physical retail stores within the district, using a screenshot from its "AT&T Stores Near You" feature to show store locations near Longview, TX (Compl. p. 5). The complaint asserts that SRv6 is a "key enabling technology for 5G" and is considered "the protocol of choice for backhaul networks for 5G and beyond," underscoring its commercial importance (Compl. ¶36).

IV. Analysis of Infringement Allegations

The complaint references, but does not attach, claim chart exhibits detailing its infringement analysis for each patent-in-suit (Compl. ¶¶ 76, 84, 91, 99, 107, 115, 122, 130). In the absence of these exhibits, the infringement theory is summarized below in prose.

The core of the infringement allegation is that AT&T's networks implement Segment Routing (SR-MPLS and SRv6) in a manner that is compliant with a set of IETF standards (RFCs 8402, 8660, 8754, 8986, etc.) as well as specifications from other standards bodies like ETSI and the ONF (Compl. ¶¶ 44-64). The complaint alleges that by implementing these standardized SR functionalities, the AT&T Networks necessarily and inherently practice the methods recited in the asserted claims of the patents-in-suit (Compl. ¶¶ 67-70). The infringement theory appears to be grounded in the premise that compliance with these public standards serves as evidence of infringement of the patented routing methods.

  • Identified Points of Contention:
    • Technical Questions: A primary evidentiary question may be whether AT&T's implementation of standardized protocols like SR-MPLS and SRv6 actually performs every step of the asserted claims. The complaint's reliance on standards compliance and public statements will likely be tested against the specific operational details of AT&T's multi-vendor network, raising the question of what specific evidence demonstrates that the accused networks practice the claimed "mapping" of identifiers or use of "scope-specific" addresses in the manner recited by the patents.
    • Scope Questions: The infringement analysis may turn on whether the terminology used in the patents, such as "node scope-specific outside-scope identifier," can be construed to read on the specific addressing and segment identifier formats used in AT&T's SRv6 or SR-MPLS implementations. A potential point of contention could be whether the standardized segment identifiers function as the specific types of "scope-specific" identifiers required by the claims, or if there is a fundamental definitional mismatch.

V. Key Claim Terms for Construction

  • The Term: "scope-specific identifier" (from ’101 Patent, Claim 1)
  • Context and Importance: This term is foundational to the alleged invention of the ’101 Patent. The infringement analysis depends on whether the identifiers used in AT&T's SR implementation are "scope-specific" in the way the patent contemplates—that is, whether their meaning is dependent on the context of a particular node or network region. Practitioners may focus on this term because it appears to describe a technical nuance beyond a generic network identifier.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The detailed description states that a scope-specific address space may be specific to various regions, such as a "site-specific, LAN-specific, subnet-specific, city-specific, business-specific, and node-specific" region, which could support a construction covering any identifier whose meaning is localized (’101 Patent, col. 11:67–12:3).
    • Evidence for a Narrower Interpretation: The abstract and claims tie the invention to the MPLS protocol, and specific embodiments illustrate the concept using MPLS label stacks (’101 Patent, Abstract; col. 3:43-45). This may support a narrower construction limited to the types of identifier mapping and label-based forwarding shown in the patent's examples.
  • The Term: "node scope-specific outside-scope identifier" (from ’998 Patent, Claim 1)
  • Context and Importance: This term is critical because it adds two layers of specificity: the identifier must be specific to the "current node" but must identify a region "outside" that node's scope. Infringement will hinge on whether AT&T's SR architecture uses identifiers that perform this dual function. Practitioners may focus on this term to dispute whether a standard segment identifier, which defines a hop in a path, meets both the "node scope-specific" and "outside-scope" limitations simultaneously.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The specification describes that a node can process a scoped protocol address to identify a destination node outside its local region, suggesting the term could cover any mechanism for routing from a local context to a remote one (’998 Patent, col. 20:56–21:5).
    • Evidence for a Narrower Interpretation: The claim requires that the identifier "does not include a network interface identifier portion," and the abstract links it to identifying a "first region of the network" (’998 Patent, Abstract). This could support a narrower construction that excludes general-purpose IP addresses or requires the identifier to point to an entire region rather than a single next-hop interface.

VI. Other Allegations

  • Indirect Infringement: The complaint does not include counts for indirect infringement. However, it alleges that AT&T introduces infringing products and services "into the stream of commerce knowing that they would be sold and/or used in this judicial district" (Compl. ¶7), which contains language that may support a later assertion of induced or contributory infringement.
  • Willful Infringement: The complaint does not contain a specific count for willful infringement. The prayer for relief, however, requests a declaration that the case is "exceptional under 35 U.S.C. § 285" and an award of attorneys' fees (Compl. p. 30), which is the procedural mechanism for seeking enhanced damages that can be based on a finding of willful infringement.

VII. Analyst’s Conclusion: Key Questions for the Case

  • A central issue will be one of technical mapping: what evidence will demonstrate that AT&T's real-world, multi-vendor network operations, which are alleged to comply with public standards, actually practice the specific and nuanced steps of the asserted claims? The case may depend on whether Plaintiff can prove that standardized Segment Routing identifiers function as the claimed "scope-specific" and "outside-scope" identifiers, or if there is a functional mismatch between the standards and the patented methods.
  • A key legal question will be one of definitional scope: can the claim terms, such as "path-based protocol address" and "node scope-specific identifier," which are described in the context of the patents' specific embodiments, be construed broadly enough to encompass the varied implementations of SR-MPLS and SRv6 that are governed by IETF, ETSI, and other industry standards?
  • A third question will be one of causation and damages: given that the patents-in-suit cover foundational aspects of Segment Routing, a technology now widely adopted in 5G and modern IP networks, a key battleground may be determining the incremental value, if any, provided by the patented inventions over the prior art and the public standards themselves, which will be central to any damages calculation.