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.


The Author

Joseph Robinson

Joseph Robinson has over 20 years of experience in all aspects of intellectual property law. He focuses his practice in the pharmaceutical, life sciences, biotechnology, and medical device fields. His practice encompasses litigation, including Hatch-Waxman litigation; licensing; counseling; due diligence; and patent and trademark prosecution. He has served as litigation counsel in a variety of patent and trademark disputes in many different jurisdictions, and has also served as appellate counsel before the Court of Appeals for the Federal Circuit. Joe also focuses on complex inter partes matters before the U.S Patent and Trademark Office, inventorship disputes, reexaminations and reissues. His experience includes numerous interferences, a particular advantage in new U.S. Patent and Trademark Office post-grant proceedings. He also counsels on patent–related U.S. Food and Drug Administration issues, including citizen petitions, Orange Book listing, and trademark issues. For more information and to contact Joe please visit his profile page at the Troutman Sanders website.

Joseph Robinson

Robert Schaffer is an intellectual property partner at Troutman Sanders. Bob applies more than 30 years of experience to IP counseling and litigation. His work includes patent procurement, strategic planning and transactional advice, due diligence investigations, district court patent cases, and Federal Circuit appeals. He regularly handles complex and high-profile domestic and international patent portfolios, intellectual property agreements and licensing, IP evaluations for collaborations, mergers, and acquisitions. In disputed court cases Bob’s work includes representing and counseling client in ANDA litigations, complex patent infringement cases and appeals, and multidistrict and international cases. In disputed Patent Office matters his work includes representing and counseling clients in interferences, reexaminations, reissues, post-grant proceedings, and in European Oppositions. For more information and to contact Bob please visit his profile page at the Troutman Sanders website.

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There are currently 2 Comments comments.

  1. Prizzi's Glory August 6, 2016 6:49 am

    The term “symbol generator” has been around for a long time in the software arts, but it can mean very different things in different contexts.

    Here is symbol generator code from a compiler.