Section 112(f) of the patent statute allows a patentee to define a structural claim element in terms of its function alone, i.e., “as a means ... for performing a specified function without the recital of structure ... in support thereof.” In that case, the claim is construed “to cover the corresponding structure ... described in the specification and equivalents thereof.” However, following Federal Circuit decisions from the 1980s, traditional “means-plus-function” claim drafting has been steadily declining. The number of issued patents including “means for” language has dropped from about 60 percent in the 1980s to less than 10 percent today.

Previously published in Law360 - November 6, 2015.