A broad class of algorithms for performing the function of a computer-implemented means-plus-function element, as opposed to a single or small set of algorithms, is not sufficiently definite to provide the requisite algorithmic structure. Here, for example, the specification’s allusion to logarithmic algorithms for generating data indicative of an audio signal was found to be insufficient to render a corresponding means-plus-function element definite because the logarithmic conversion function could be implemented through multiple logarithmic algorithms, none of which the specification specifically described. “Disclosing the broad class of [algorithms] does not limit the scope of the claim to the ‘corresponding structure, material, or acts’ that perform the function, as required by Section 112.” It may therefore be best to ensure that the specification describes a relatively specific algorithm or set of algorithms for any means-plus-function element, rather than relying on reference to a broad class of algorithms.
Background / Facts: The patents being asserted here are directed to an ear implant with an internal implantable cochlear stimulator (ICS), which processes audio to stimulate the cochlea––the organ that converts sound to nerve impulses. The claims recite “means for generating data indicative of the audio signal.” It is not disputed that this is a means-plus-function limitation and that the corresponding structure is a microprocessor. Although the specification mentions using logarithmic conversion for this purpose, it does not describe which of multiple logarithmic algorithms is to be employed.
Issue(s): Whether, as required for definiteness under 35 U.S.C. § 112, second paragraph, the specification’s allusion to a general class of logarithmic algorithms for generating data indicative of an audio signal provides the requisite algorithmic structure for the microprocessor to use to perform the recited function.
Holding(s): No. “[T]he  patent does not disclose an algorithm, or even a small set of algorithms for performing the claimed logarithmic conversion function. Disclosing the broad class of [logarithmic conversion] does not limit the scope of the claim to the ‘corresponding structure, material, or acts’ that perform the function, as required by Section 112.  Although [the patentee] argue[s] that a person of ordinary skill in the art would know of potential logarithmic conversion functions to implement , this does not create structure in the patent where there was none to begin with.”