Claims Directed to a Network Packet Monitor Held Patent Eligible

In Packet Intelligence LLC v. Netscout Systems, Inc., No. 19-2041 (Fed. Cir., July 14, 2020) the U.S. Court of Appeals for the Federal Circuit upheld the patent-eligibility of a network packet monitor, finding its claims directed to non-abstract subject matter in light of details included in the technical specifications.  This is an important case for several reasons.  First, it is a reminder that in writing software patent applications we should describe the invention in terms of the technical problem associated with the prior art systems and the technical solution for overcoming those problems.  The technical solution should specifically point out the manner in which the invention overcomes the technical problems of the prior art systems.   Second, it is a reminder that although the claims should be interpreted in light of the specification, we should be careful not to import language from the specification into the claims.  See, the dissenting opinion of Judge Reyna, which is very interesting.   It highlights that the claims themselves should describe the manner in which the invention overcomes the technical problems associated with the prior art systems and should not simply recite a technical result achieved by the invention.  

With the above overview, let’s get into it!

Packet Intelligence sued Netscout Systems in the District Court for the Eastern District of Texas for infringement, by Netscout’s “G10” and “GeoBlade” products, of US Patents No. 6,665,725 (the ‘725 patent), No. 6,839,751 (“the ’751 patent”), and No. 6,954,789 (“the ’789 patent”). Netscout argued that the “claims are directed to the abstract idea of collecting, comparing, and classifying packet information.” The District Court and jury disagreed, finding all three patents eligible under 35 U.S.C. § 101 and infringed. Netscout appealed. On appeal, the Federal Circuit affirmed, holding that the disputed claims were patent-eligible.

The representative claim of the asserted claims from the three patents, claim 19 of the ‘789 patent, recites:

19. A packet monitor for examining packets passing through a connection point on a computer network, each packet conforming to one or more protocols, the monitor comprising:
(a) a packet acquisition device coupled to the connection point and configured to receive packets passing through the connection point;
(b) an input buffer memory coupled to and configured to accept a packet from the packet acquisition device;
(c) a parser subsystem coupled to the input buffer memory and including a slicer, the parsing subsystem configured to extract selected portions of the accepted packet and to output a parser record containing the selected portions;
(d) a memory for storing a database comprising none or more flow-entries for previously encountered conversational flows, each flow-entry identified by identifying information stored in the flow-entry;
(e) a lookup engine coupled to the output of the parser subsystem and to the flow-entry memory and configured to lookup whether the particular packet whose parser record is output by the parser subsystem has a matching flow-entry, the looking up using at least some of the selected packet portions and determining if the packet is of an existing flow; and
(f) a flow insertion engine coupled to the flow-entry memory and to the lookup engine and configured to create a flow-entry in the flow-entry database, the flow-entry including identifying information for future packets to be identified with the new flow-entry, the lookup engine configured such that if the packet is of an existing flow, the monitor classifies the packet as belonging to the found existing flow; and if the packet is of a new flow, the flow insertion engine stores a new flow-entry for the new flow in the flow-entry database, including identifying information for future packets to be identified with the new flow-entry,
wherein the operation of the parser subsystem depends on one or more of the protocols to which the packet conforms.

To provide context, communication over a computer network is performed through packets of information sent to and from individual computers. A stream of packets between two computers is called a connection flow. In practice, however, a software application may utilize streams at multiple times (such as querying a database in response to user requests), which is not easily monitored by looking at connection flows alone. The ‘725 ‘751 and ‘789 specifications explain the “conversational flow,” which groups packets by application in an application-specific view of network traffic in order to generate useful metrics and analytics. Claim 19 of the ‘789 patent proposes a packet monitor which is capable of identifying such conversational flows from a stream of packets.

35 U.S.C. §101 allows inventors to obtain a patent on “any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof.” This provision, as interpreted by the courts, does not include inventions directed toward “laws of nature, natural phenomena, and abstract ideas” (Mayo Collaborative Services v. Prometheus Labs. Inc., No. 10-1150, S. Ct., March 20, 2012). To assess whether a claim falls within this exception category of 35 U.S.C. §101, the Supreme Court formulated a two-prong test in Alice Corp. v. CLS Bank International, No. 13-298 (S. Ct., June 19, 2014). In step one of Alice, it is determined whether a claim is directed toward an “abstract idea” or otherwise patent-ineligible subject matter. Should the claim not be found directed to patent-ineligible subject matter, it is patent eligible under 35 U.S.C. §101. Only should the claim fail to pass muster in step one do the courts proceed to step two, seeking a “saving inventive concept” to determine whether the additional claim elements alone, or proposed as a combination, render the claim from abstractness to a patent eligible idea.

In applying step one of Alice, the Federal Circuit found the asserted claims amounted to a new and useful improvement to computer networks and therefore patent-eligible. The Federal Circuit concludes that “the specifications explain that known network monitors were unable to identify disjointed connection flows to each other, and the focus of the claims is a specific improvement in computer technology: a more granular, nuanced, and useful classification of network traffic,” and that “the specifications likewise explain how the elements recited in the claims refer to specific technological features functioning together to provide that [improvement], rather than an abstract result.” Supporting this finding, the Federal Circuit pointed to Enfish, LLC v. Microsoft Corp., No. 15-1244 (Fed. Cir., May 12, 2016), where they found a self-referential table not directed to an abstract idea because “the specification taught that the self-referential table functioned differently from conventional databases, providing increased flexibility, faster search times, and smaller memory requirements,” a concrete improvement to the way computers operate. Similarly, the Federal Circuit referenced SRI International, Inc. v. Cisco Systems, Inc., No. 17-2223 (Fed. Cir., March 20, 2019), where a method of identifying suspicious computer network activity was found not directed to an abstract idea, as the claims were “necessarily rooted in computer technology in order to solve a specific problem in the realm of computer networks” and therefore not directed to an abstract idea merely using computers as a tool, thus patent-eligible. The Federal Circuit “relied on statements in the specification that the claimed invention purported to solve weaknesses in the prior art by providing a framework for recognition of global threats to interdomain connectivity” in drawing this conclusion.

Judge Reyna wrote a dissenting opinion on the majority’s findings in regards to 35 U.S.C. §101. In his dissent, he views that the “claims are directed to the abstract idea of identifying data packets as belonging to ‘conversational flows’ rather than discrete ‘connection flows.’” He argues that the majority found the asserted claims eligible on the basis that they claimed a “technological solution to a technological problem,” yet “the ‘solution’ of classifying network traffic according to conversational flows rather than connection flows is conceptual, not technological, in the absence of specific means by which that classification is achieved.” He noted the claims’ reference to unspecified “identifying information” required in order to achieve the classification of connection flows, where “the claims do not disclose how the desired result of ‘identif[ying]’ packets as belonging to a conversational flow is achieved.” Emphasis on specifying the method of achieving the desired result stems from the cited SAP America, Inc. v. Investpic LLC, No. 17-2081 (Fed. Cir., May 15, 2018), which held that a claim should provide “the specificity required to transform a claim from one claiming only a result to one claiming a way of achieving it.” Reyna concluded that “while a claim must be read ‘in light of the specification’ to understand what is claimed and the relative significance of the claimed components, … a court cannot rely on unclaimed details in the specification as the ‘focus’ of the claim for § 101 purposes.”

Ultimately, the Federal Circuit found that the asserted claims taken together with the included specifications, amounted to a “technological solution to a technological problem” in step one of Alice, and was therefore patent-eligible under 35 U.S.C. §101 without need for consideration under step two.

Practice Notes:

• Do include in the specification the concrete technological problem solved by the claimed invention
• Do include in the specifications the concrete means by which the invention  improves upon or solves the stated problems in the prior art
• Do include in the claims the concrete means by which the claimed invention achieves the improvements or results described in the specification