CAFC: Software means plus function claims Indefinite for failure to disclose algorithm

federal-circuit-cafc-3Advanced Ground Info. Sys. v. Life360, Inc. (Fed. Cir. July 28, 2016) (Before Mayer, Moore, and Wallach, J.) (Opinion for the court, Wallach, J.)

The patents-in-suit relate to methods, devices, and systems for establishing a communication network for users of mobile devices. They describe a cellular communication system allowing multiple phone users to monitor others’ locations and statuses through a visual map. The two patents include claims that have a “symbol generator,” which generates symbols representing each user in a network on the display of a user’s cellular phone. The claims also recite that the cellular phones comprise “CPU Software.” AGIS is the owner of these patents.

Life360 created smartphone software designed to allow families to view one another on a map, receive alerts when loved ones arrive at various destinations, and communicate with one another. AGIS sued Life360 for infringing certain claims of both its patents. Life360 asserted that the terms “symbol generator” and “CPU software” invoked means-plus-function language, but the patents failed to disclose adequate structure, making the claims indefinite under 35 U.S.C. § 112. The district court agreed, and AGIS appealed.


The asserted claims did not include the word “means” but the district court still held that they intended to invoke the “means plus function” provisions of paragraph 6 of §112. The Federal Circuit held that the “symbol generator” did invoke this paragraph because it failed to describe a sufficient structure and otherwise recited abstract elements “for” causing actions that could perform functions. There was no error in the district court’s finding that “symbol generator” was not used in “common parlance or by persons of skill in the pertinent art to designate structure.” The testimony of Dr. Golberg, AGIS’s expert, included a statement that “symbol generator” was coined for the patents, which was contrary to AGIS’s contention that “symbol generator” refers to a class of structures instead of a particular structure. The combination of “symbol” and “generator” suggested that it was an abstraction describing the function being performed. The Court also noted that the term by itself did not identify a structure by stating its function.

The Court also affirmed that the this means-plus-function term was indefinite. In the case of computer-implemented functions, the specification must disclose an algorithm for performing the claimed function. The patents-in-suit did not disclose an operative algorithm for the claimed “symbol generator.” The function of generating symbols must be performed by some component of the patents, but the patents did not describe this component.

A patentee cannot claim a means for performing a specific function and then disclose a “general purpose computer” as the structure performing that function. The specification must disclose an algorithm in hardware or software for performing the stated function.

Parker Hancock and Puja Dave also contributed to this summary.



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