There are many benefits to employing means + function claiming under 35 USC §112(f).  The Federal Circuit recently pointed out a new one: protecting your claims from the application by the Broadest Reasonable Interpretation (BRI) claim construction paradigm employed by the USPTO in reexaminations, reissues, PGRs, IPRs and CBMRs.  In IPCOM GmbH & Co. v. HRC Corp., [2016-1474] (July 7, 2017) —previously discussed here — the Federal Circuit said that the PTO may not disregard the structure disclosed in the specification corresponding to means + function elements when rendering a patentability determination.

Thus, including some means + function claims in a claim set may prevent the Patent Office from using BRI to stretch an otherwise valid claim to the point of invalidity.  Of course there are other benefits from means + function claiming, including:

• It allows “gerrymandering” of claim scope through selectively including or excluding corresponding structures in the specification.
• It helps avoid problems with the disclosure/dedication doctrine, where disclosed but unclaimed subject matter cannot be covered by the doctrine of equivalents, and is dedicated to the public.
• When claims are amended using means + function elements, statutory equivalents under §112(f) are available, even if prosecution history estoppel bars the doctrine of equivalents.

All of which suggest that means + function elements can be a valuable tool for getting the maximum claim scope.