U.S. practitioners usually dislike means-plus-function language these days, at least in software cases. However, applications inbound from other jurisdictions may not be drafted with U.S. means-plus-function hazards in mind. Practitioners filing applications in the U.S., whether original or claiming foreign priority, should be reluctant to include means-plus-function language in U.S. claims. I would even be reluctant to use means-plus-function language where other claims were plainly drafted without it, absent a particular reason to do so. Why invite a claim construction inquiry into whether a specification discloses — and enables — a particular functionality? Further, claimed algorithms should always be disclosed in as much detail as possible because it seems that some of the above reasoning could be applied to claims lacking means-plus-function language.
The latest example of the danger of drafting software patent claims to include means-plus-function limitations comes from Eon Corp. IP Holdings LLC v. AT&T Mobility LLC, No. 2014-1392 (Fed. Cir. May 6, 2015).
According to the court, the limitations in the claims required “special programming,” and were not simply an extension of the operation of a microprocessor. Because the claimed “means” were not described in the specification, the claims, all governed by 35 U.S.C. § 112, have been held invalid as indefinite.
The latest example of the danger of drafting software patent claims to include means-plus-function limitations comes from Eon Corp. IP Holdings LLC v. AT&T Mobility LLC, No. 2014-1392 (Fed. Cir. May 6, 2015).
According to the court, the limitations in the claims required “special programming,” and were not simply an extension of the operation of a microprocessor. Because the claimed “means” were not described in the specification, the claims, all governed by 35 U.S.C. § 112, have been held invalid as indefinite.