While patent applicants are free to
define terms in their patent applications, a recent US Federal
Circuit case highlights the risks of using coining terms in patent
AGIS v Life3601
involved a pair of patents related to establishing a communication
network for users of mobile devices.2 Each of the claims
at issue included the coined term "symbol generator". The
US Federal Circuit held that the claims were invalid because the
term "symbol generator" was indefinite.
In the United States, claim
elements defined in a functional rather than structural manner may
be identified as "means-plus-function" claim elements.
Means-plus-function interpretation is usually applied when the term
"means" is used in a claim. The absence of
"means" language creates a rebuttable presumption that
the means-plus-function interpretation should not apply. This
presumption can be overcome by showing that a person of ordinary
skill in the relevant field would not understand the claim term to
have a sufficiently definite meaning as the name for
claim elements are interpreted narrowly to cover only the specific
structures disclosed in the application for accomplishing a
function, rather than the function itself. As a result, in order
for the claim element to be definite, the specification must
include adequate disclosure of structure that performs the
function. When a function is computer-implemented, an algorithm for
performing that function is usually required unless the function is
a basic operation such as processing or storing.4 A more
detailed discussion of the disclosure required for
means-plus-function claim elements in software patents can be found
In AGIS, the term
"symbol generator" was interpreted as a
"means-plus-function" element because it failed to
describe a sufficient structure and merely recited abstract
elements for causing actions or performing functions. The Federal
Circuit found that "symbol generator" was not used in
common parlance by persons of skill in the field to designate
structure. Rather, the term "symbol generator" was coined
specifically for the patents at issue. The Federal Circuit held
that even if the terms "symbol" and "generator"
are individually terms of art in computer science, the term
"symbol generator" used in the claims suggests an
abstraction that describes the function being performed, and does
not by itself identify a structure by its function.
Because the term "symbol
generator" was interpreted as means-plus-function language,
the specification required adequate disclosure of structure that
could provide the claimed function. However, the Federal Circuit
found that the patents in AGIS did not disclose an
operative algorithm for the symbol generator. While the
specifications indicated that symbols were generated via a series
of databases, this was merely the medium through which the symbols
were generated and not an operative algorithm. Accordingly, the
Federal Circuit concluded that the specifications did not disclose
sufficient structure to provide the symbol generator function.
AGIS highlights the risks
of using coined terms in patent claims, particularly for
computer-implemented inventions. Specifically, coined terms may be
treated as means-plus-function elements and interpreted to cover
only the specific corresponding structures disclosed in the
specification. Accordingly, if the specification does not provide a
clear and complete disclosure of structure that performs the
function of the coined term the patent may be invalidated.
While it can be tempting to use
coined terms when defining the scope of a claim, it would be
prudent to avoid coined terms in the claims of computer-implemented
inventions. If coined terms cannot be avoided, patent applicants
should be sure to disclose detailed algorithms or processes for
performing the claimed function in the specification and/or the
figures of a patent application to ensure the claims are not
1. Advanced Ground Information Systems, Inc v
Life360, Inc, (Fed Cir, July 28, 2016) [AGIS].
2. U.S. Patent No. 7,031,728 and U.S. Patent No.
3. Williamson v Citrix Online, LLC, 792 F3d 1339
(Fed Cir 2015) (en banc).
4. In re Katz Interactive Call Processing Patent
Litigation, 639 F.3d 1303 (Fed. Cir. 2011).
The content of this article is intended to provide a
general guide to the subject matter. Specialist advice should be
sought about your specific circumstances.
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On November 9, 2016, final amendments to the Regulation respecting the language of commerce and business and the Regulation defining the scope of the expression "markedly predominant" for the purposes of Charter of the French Language were published.
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