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
claims.
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
