A software patent means-plus-function claim is indefinite where the specification fails to disclose an algorithm that performs the recited function. The Federal Circuit has now held that where a means limitation is associated with multiple functions, a claim is indefinite where the patent specification discloses only one of the functions. Noah Systems, Inc v. Intuit, Inc., No. 2011-1390 (Fed. Cir. April 9, 2012).
Noah asserted against Intuit three independent claims of U.S. 5,875,435 (including claims added during a re-examination by the U.S. Patent and Trademark Office). All of the asserted claims included substantially the following recitation:
means for providing access to said file of said financial accounting computer for said first entity and/or agents of said first entity so that said first entity and/or said agent can perform one or more activities selected from the group consisting of entering, deleting, reviewing, adjusting and processing said data inputs.
During claim construction proceedings a special master provided a report and recommendation, accepted by the district court, concluding that the "'access means' limitation was indefinite" because "the specification failed to disclose an algorithm by which the financial accounting computer was programmed to perform the limitation's function." Noah requested reconsideration, arguing that the special master erred in reaching this conclusion without the aid of expert testimony in assessing how one skilled in the art would have understood the specification. The special master disagreed, finding only "functional descriptions and not structure" in the patent specification. The special master further made a recommendation, adopted by the court, to grant Intuit's motion for summary judgment of invalidity.
Considering Noah's appeal, the Federal Circuit first addressed Intuit's argument that Noah was relying on a claim construction proffered for the first time on appeal, and therefore waived. The court disagreed, finding that "all portions of the specification that Noah relies upon before this court were cited" in proceedings before the district court. Therefore, the court turned "to the merits of Noah's claim construction and invalidity arguments."
The court began by noting that, while the question of indefiniteness hinges on the understanding of one skilled in the art, expert testimony "cannot supplant the total absence of structure from the specification." Further, the specification was required to disclose a structure that was "more than simply a general purpose computer or microprocessor." Some algorithm for performing the claimed function must be disclosed.
Here, the court had first to decide whether this case fell into a category of cases in which no algorithm was disclosed, or into a category of cases in which an algorithm was disclosed, but inadequately. The specification, "contrary to the district court's conclusion," did disclose "an algorithm for the passcode function associated with the 'access means.'" However, the recited access means really recited two functions: "(1) providing access to the file," a structure for which was disclosed, and "(2) once access is provided, enabling the performance of delineated operations," for which no structure was disclosed. At most, regarding the second function of performing certain operations (i.e, " one or more activities selected from the group consisting of entering, deleting, reviewing, adjusting and processing said data inputs"), the specification simply described the operations as included at a portion of a flow chart. Moreover, a "partial disclosure" case such as this should be treated as a "no disclosure" case because there was a recited function for which there was no disclosed structure, even if there was a disclosed structure for another recited function.
Accordingly, the court concluded that:
Computer-implemented means-plus-function claims are indefinite unless the specification discloses an algorithm to perform the function associated with the limitation. When the specification discloses an algorithm that only accomplishes one of multiple identifiable functions performed by a means-plus-function limitation, the specification is treated as if it disclosed no algorithm. Because the ’435 patent’s specification discloses an algorithm for performing only one of the functions associated with the “access means” limitation, the limitation is indefinite. All of the asserted claims contain this limitation; the asserted claims are, therefore, invalid as indefinite.