Software claims patent-eligible when directed to functionality improvements

"Gliwice Radio Tower (Radiostacja Gliwicka) at Night #2" by karol.cc is licensed under CC BY-SA 2.0

The Federal Circuit has reversed a decision by a federal court that a patent claim involving radio communications was abstract and thus not patent-eligible.

Mentone Solutions LLC v. Digi International Inc. involved a patent that “relates to dynamic resource allocation in general packet radio systems.”

Mentone sued for infringement, and the defendants moved to dismiss, claiming that the patent claims were patent-ineligible under 35 U.S.C. § 101, which states:

“[w]hoever invents or discovers any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof,” may obtain a patent.

Under the US Supreme Court’s decision in Alice Corp. v. CLS Bank Int’l, “[l]aws of nature, natural phenomena, and abstract ideas are not patent eligible.”

The district court granted the motion to dismiss, holding that the claim at issue was patent ineligible for being “directed to the abstract idea of receiving a USF and transmitting data during the appropriate timeslots.”

Also, said the district court,

the shifted uplink status flag combined with the “abstract idea, functional limitations, and anything else” is not significantly more than a claim to the abstract idea.

“USF” means “uplink status.” As the court explained, the “patent relates to dynamic resource allocation in general packet radio systems.”

As the circuit court described,

In those systems, a number of mobile stations communicate with a single network through physical links called Packet Data Channels (PDCHs). …. When the mobile stations receive information from the network, they are engaging in downlink (DL) communication, and when the mobile stations are transmitting information to the network, they are engaging in uplink (UL) communication….. These mobile stations communicate within time frames, each divided into eight timeslots.

The patent identified two restrictions:

First, “the mobile station is not able instantly to switch from a receive condition to a transmit condition or vice versa.” …This turn-around time, along with the time needed to perform certain measurements, prevents certain multislot patterns from functioning. …

Second, in systems using an extended dynamic allocation method, there is a fixed relationship between the downlink slot in which a valid USF is received and the uplink slot in which transmission begins; a mobile station’s receipt of a valid USF in a certain downlink timeslot indicates the availability for that station to begin transmission in the corresponding uplink slot

The purported invention focuses on the latter restriction:

It allows a mobile station access to previously restricted multislot configurations through “altering the fixed relationship in the timing of the downlink allocation signalling [sic] and subsequent uplink transmission for certain classes of mobile station.”

The circuit court concluded:

claim 5 is directed to a patent-eligible improvement to computer functionality, namely permitting additional multislot configurations for certain classes of mobile stations using extended bandwidth allocation…. It adds this capability through using a shifted USF that breaks the fixed relationship in the timing of downlink allocation signaling (i.e., receipt of a USF on a timeslot) and subsequent uplink transmission.

Thus, “The claim does not merely recite generalized steps to be performed on a computer” and is therefore patent-eligible.