Federal Circuit Holds Coined Phrases to Be Means-Plus-Function, and Indefinite

In Advanced Ground Information Systems, Inc. v. Life360, Inc., No. 2015-1732 (Fed. Cir. July 28, 2016), the Federal Circuit cautioned against coining verbal nouns and phrases without specifying sufficient structure or algorithms in the patent specification. The court affirmed a finding of indefiniteness of claims of U.S. Patent Nos. 7,031,728 and 7,672,681, and held the claims invalid under 35 U.S.C. § 112.

The phrase at issue was “symbol generator,” which was recited in each of the asserted claims. While the phrase does not include the word “means,” the Federal Circuit found that “the term ’symbol generator’ is analogous to a ‘means for generating symbols’ because the term is simply a description of the function performed.” Op. at 8. The Federal Circuit further found, based on expert testimony, that “the term ’symbol generator’ is a term coined for the purposes of the patents-in-suit.” Op. at 10. Because “symbol generator” is not a term of art that requires particular structure, the Federal Circuit treated it as a means-plus-function limitation subject to § 112, ¶6 (or post-AIA §112(f)).

Means-plus-function limitations are indefinite if not defined in the specification via structure or algorithms. Here, the Federal Circuit found that both were lacking with regard to the “symbol generator.” “The function of generating symbols must be performed by some component of the patents-in-suit; however, the patents-in-suit do not describe this component.” Op. at 13. “In the case of computer-implemented functions, we require that the specification disclose an algorithm for performing the claimed function.” Op. at 12 (internal quotations omitted). The patents at issue, however, “do not disclose an operative algorithm for the claim elements reciting ‘symbol generator.’” Op. at 13.

Interestingly, the fact that both “symbol” and “generator” are terms of art in computer science was not enough to suggest any structural limitations. “Irrespective of whether the terms ’symbol’ and ‘generator’ are terms of art in computer science, the combination of the terms as used in the context of the relevant claim language suggests that it is simply an abstraction that describes the function being performed (i.e., the generation of symbols).” Op. at 10. “[T]he claim term ‘symbol generator,’ by itself, does not identify a structure by its function.” Op. at 11.