WSOU Investments LLC v. Hewlett Packard Enterprises Co

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: WSOU Investments, LLC d/b/a Brazos Licensing and Development (Delaware)
  • Defendant: Hewlett Packard Enterprise Company (Delaware)
  • Plaintiff’s Counsel: Brown Rudnick LLP; The Mort Law Firm, PLLC
• Case Identification: 6:20-cv-00727, W.D. Tex., 08/12/2020
• Venue Allegations: Venue is alleged to be proper based on Defendant having a regular and established place of business within the Western District of Texas, being registered to do business in Texas, and having transacted business and committed alleged acts of infringement in the district.
• Core Dispute: Plaintiff alleges that Defendant’s enterprise networking routers and switches infringe a patent related to methods for determining optimal data switching paths in a label-switched communication network using multiple criteria.
• Technical Context: The technology concerns Multi-Protocol Label Switching (MPLS) traffic engineering, a foundational method for managing data flow and ensuring quality of service in large-scale corporate and internet service provider networks.
• Key Procedural History: The complaint does not mention any prior litigation involving the patent-in-suit, any post-grant proceedings before the U.S. Patent and Trademark Office, or any prior licensing history.

Case Timeline

Date	Event
2002-12-17	U.S. Patent No. 7,443,832 Priority Date
2008-10-28	U.S. Patent No. 7,443,832 Issue Date
2020-08-12	Complaint Filing Date

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

U.S. Patent No. 7,443,832 - "Device for Determining Switching Paths in a Label Switched Communication Network in the Presence of Selection Attributes"

• Patent Identification: U.S. Patent No. 7,443,832, "Device for Determining Switching Paths in a Label Switched Communication Network in the Presence of Selection Attributes," issued October 28, 2008 (the "’832 Patent"). (Compl. ¶18).

The Invention Explained

• Problem Addressed: The patent describes a problem in label-switched networks (like MPLS) where path calculation based on a single criterion, such as the shortest path, often leads to network congestion on popular routes while other viable routes remain underutilized. This approach is inefficient and can degrade network performance. (’832 Patent, col. 4:36-44).
• The Patented Solution: The invention proposes a device and method that determine a switching path by simultaneously considering multiple criteria (e.g., bandwidth, path duration). It works by first calculating all possible paths, then "deducing an ideal solution" which represents the theoretical best performance across all criteria. Each possible path is then assigned an "interest value" based on its proximity to this ideal solution. Finally, the device selects a path from the classified list, allowing for a more balanced and optimized use of network resources. (’832 Patent, Abstract; col. 4:5-37).
• Technical Importance: This multi-criteria approach to path selection enables more sophisticated traffic engineering, allowing network operators to better manage quality of service (QoS) and make more efficient use of the entire network topology. (’832 Patent, col. 5:55-65).

Key Claims at a Glance

• The complaint asserts at least independent claim 1. (Compl. ¶32).
• Independent Claim 1 recites a device comprising a memory and a processing means for performing the following steps:
  • Receiving a path set-up request and determining at least two criteria associated with the data stream.
  • Ensuring the connectivity of the network routers.
  • Calculating possible paths between a departure and destination node based on the criteria, and then deducing an "ideal solution" from the performance of those possible paths.
  • Assigning each possible path an "interest value" based on the ideal solution and classifying the paths accordingly.
  • Selecting a path from the classified list and associating a label with the data stream to switch it via the selected path.
• The complaint does not explicitly reserve the right to assert dependent claims but requests judgment that Defendant infringes "one or more claims." (Compl. p. 14).

III. The Accused Instrumentality

Product Identification

• The HPE HSR6800 Router Series, HPE A880 Router Series, and the HPE 5820X Switch Series (the "Accused Products"). (Compl. ¶20).

Functionality and Market Context

• The complaint describes the Accused Products as powerful networking routers and switches that provide robust routing capabilities, including MPLS, for enterprise data centers. (Compl. ¶21). They are alleged to establish "Constraint-Based Label Switched Paths (CR-LSPs)" by calculating an optimal path through a network of routers. (Compl. ¶25). This calculation is allegedly performed using a "Constraint-based Shortest Path First (CSPF)" algorithm that considers various network constraints and traffic engineering attributes stored in a "Traffic Engineering Database (TEDB)." (Compl. ¶¶ 26-27). The complaint includes a diagram, Figure A, illustrating how Label Switched Paths (LSPs) are established through multiple routers. (Compl. ¶25, Fig. A).
• The Accused Products are positioned as core components for building and managing complex, high-performance data center networks. (Compl. ¶¶ 15, 21).

IV. Analysis of Infringement Allegations

’832 Patent Infringement Allegations

Claim Element (from Independent Claim 1)	Alleged Infringing Functionality	Complaint Citation	Patent Citation
a memory means for storing a table of correspondences between sets of service data and information data representative of at least two chosen criteria and a descriptive structure containing information data representative of a state of utilization and of a topology of the network...	The Accused Products allegedly include a "Traffic Engineering ('TE') Database ('TEDB')" which stores "TE attributes" of network links, including "service data and the information data representative of the chosen criteria" and information on network topology and utilization.	¶26	col. 4:6-15
a processing means for: a) receiving a path set-up request... and for determining in said table at least two criteria...	The Accused Products allegedly perform "Dynamic CR-LSP establishment" which receives a path request and considers "service data (i.e., the QoS parameters)" and criteria like "bandwidth, affinity, setup and holding priorities, explicit path, etc."	¶27	col. 4:16-24
b) ensuring the connectivity of said multiplicity of label switched routers, on the basis of information data stored in said descriptive structure;	The Accused Products allegedly ensure connectivity using the TEDB and a "failed link timer" feature, which maintains the state of network links. The complaint provides a screenshot, Figure B, showing the command to configure this timer.	¶28	col. 4:25-29
c) calculating from among said label switch routers possible paths... taking account of at least one of said two criteria... and then deducing an ideal solution from performances of said possible paths on at least one of said criteria;	The Accused Products allegedly use the CSPF algorithm to calculate paths based on TE attributes (criteria). The complaint alleges that "CSPF deduces an ideal solution based on the constraints (i.e., the criteria)."	¶¶29-30	col. 4:29-34
d) assigning each possible path an interest value taking account of said ideal solution and then classifying said possible paths taking account of their respective interest values;	When multiple paths have the same metric, the Accused Products allegedly use a "tie-breaking method" to select one. The complaint alleges that "based on the interest values the paths are classified." Figure C in the complaint shows configuration options for this tie-breaking.	¶¶30-31	col. 8:1-15
e) selecting a path from among said classified possible paths and then associating with said stream to be switched to a label representative of said selected path...	A path is allegedly selected from the classified paths. A "label distribution protocol (LDP)" then advertises labels and reserves resources along the path, and the stream is switched to the destination node via that path.	¶31	col. 4:34-37

• Identified Points of Contention:
  • Scope Questions: A central question may be whether the accused "CSPF algorithm," which typically finds the shortest path that satisfies a set of constraints, performs the same function as "deducing an ideal solution" as described in the patent. The patent teaches creating a theoretical ideal point from the best values for each criterion, a potentially different process than finding a single real path that meets minimum thresholds. (’832 Patent, col. 7:33-52).
  • Technical Questions: The complaint equates the accused products' "tie-breaking method" with the claimed step of "assigning each possible path an interest value." An issue for the court may be whether the accused functionality—selecting a path based on lowest bandwidth usage or other simple rules—is technically equivalent to calculating an "interest value" using a "Tchebychev function" as described in the patent’s preferred embodiment. (’832 Patent, col. 8:4-15; Compl. ¶31, Fig. C).

V. Key Claim Terms for Construction

• The Term: "ideal solution"

  • Context and Importance: This term is the foundation of the patent's multi-criteria optimization process. The infringement case hinges on whether the accused products' path computation method can be characterized as deducing an "ideal solution."
  • Evidence for a Broader Interpretation: The complaint alleges that the CSPF algorithm "deduces an ideal solution based on the constraints (i.e., the criteria)," suggesting that any process that finds a "best" path based on multiple inputs could fall within the term's scope. (Compl. ¶30).
  • Evidence for a Narrower Interpretation: The specification provides a specific definition, describing the ideal solution as a vector of components where each component is the "best performance value observed over the possible paths" for a given criterion. This theoretical "ideal path" may not exist as a single, connectable route. (’832 Patent, col. 7:33-52). This detailed description may support a narrower construction limited to this specific method.

• The Term: "interest value"

  • Context and Importance: This term defines how potential paths are ranked. Its construction is critical for determining if the accused tie-breaking mechanism infringes.
  • Evidence for a Broader Interpretation: Practitioners may argue that any numerical or logical ranking used to select from among multiple valid paths constitutes an "interest value." The complaint's allegation that "based on the interest values the paths are classified" after a tie-breaking method is applied could support this view. (Compl. ¶31).
  • Evidence for a Narrower Interpretation: The specification teaches a specific calculation for the interest value using a "standard scalarization function, such as a Tchebychev function," which quantifies the "performance difference between a possible path . . . and the ideal path." (’832 Patent, col. 8:4-15). This may support a narrower definition that requires a specific mathematical comparison to the "ideal solution," rather than a simple tie-breaking rule.

VI. Other Allegations

• Indirect Infringement: The complaint alleges induced infringement, stating that Defendant provides "operating manuals, and other instructions" that direct customers to use the accused products in an infringing manner. (Compl. ¶35). It also alleges contributory infringement on the basis that the products contain "special features," such as MPLS services, that are material to the invention and not staple articles of commerce with substantial non-infringing uses. (Compl. ¶¶36-38).
• Willful Infringement: The willfulness allegation is based on alleged knowledge of the ’832 Patent "since at least the date of service of this Complaint." (Compl. ¶34). The Plaintiff seeks enhanced damages, suggesting an intent to prove post-suit willfulness. (Compl. p. 14).

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

• A core issue will be one of definitional scope: can the patent's terms "ideal solution" and "interest value," which the specification describes using a specific multi-vector optimization and a Tchebychev function, be construed broadly enough to read on the accused products' alleged use of a Constraint-based Shortest Path First (CSPF) algorithm with secondary tie-breaking rules?
• A key evidentiary question will be one of functional equivalence: does the accused products' process of finding a single shortest path that satisfies constraints, and then applying simple tie-breaking logic, perform substantially the same function, in substantially the same way, to achieve substantially the same result as the patent's claimed method of calculating a theoretical ideal point and then ranking all possible paths based on their mathematical distance from that point?