The US Court of Appeals for the Federal Circuit concluded that a representative claim was directed to a patent-eligible improvement to computer functionality, and therefore reversed a decision authored by Judge Leonard P. Stark as a sitting judge in the US District Court for the District of Delaware. Mentone Solutions LLC v. Digi International Inc., Case Nos. 21-1202, -1203 (Fed. Cir. Nov. 15, 2021) (Moore, C.J.) (nonprecedential).

Mentone Solutions sued Digi International for infringement of Mentone’s patent directed to an improvement in dynamic resource allocation in a GPRS cellular network utilizing shifted uplink status flags (USF). Digi moved to dismiss under Fed. R. Civ. P. 12(b)(6), arguing that the patent claims were not patent-eligible under 35 U.S.C. § 101. The district court granted the motion to dismiss, holding that the representative claim was patent-ineligible for being “directed to the abstract idea of receiving a USF and transmitting data during the appropriate timeslots.” Mentone appealed.

The Federal Circuit began its analysis with a detailed explanation of the claimed technology and how its use of a “shifted USF” improved the normal operation of the communication system, noting that the shifted USF specifically allowed a mobile station to access previously restricted multi-slot configurations.

Reviewing the district court’s § 101 eligibility determination de novo, the Federal Circuit applied the Supreme Court’s two-step Alice framework, first determining whether the representative claim was directed to an abstract idea. The Court explained that in cases involving software, step one often turns on whether the claim focuses on specific asserted improvements in the computer’s capabilities rather than on an abstract idea that merely invoked a computer as a tool.

The Federal Circuit compared the claim in issue to those at issue in Packet Intelligence v. NetScout Sys., in which the Court found that the challenged claims were directed to a problem unique to computer networks and that the patent specification provided details on how the solution to the network problem was achieved. In Packet Intelligence, the Court looked to the patent specification to inform its understanding of the claimed invention and found that the specification made clear that the claimed invention solved a challenge unique to computers.

Similarly, in this case, the Federal Circuit explained that the representative claim did not recite generalized steps to be performed on a computer but rather a particular method of breaking the timing between the downlink USF and the subsequent uplink transmission. The Court noted that the term “shifted USF” was coined by the inventor, and that the specification and figures informed the Court’s understanding of the term, the claimed invention, the technical solution and how the elements of the claim work together to provide the solution. The Court concluded that the claimed invention solved a challenge unique to computer networks and was directed to patent-eligible improvements in computer functionality.

The Federal Circuit rejected the district court’s characterization of the claim as directed to the abstract idea of “receiving a USF and transmitting data during the appropriate timeslots.” The Court found that the district court’s formulation was an over-simplified high-level description of how USFs operate in general that failed to appreciate the operation and use of the claimed shifted USF and other related features.