Identifying Class of Algorithms Insufficient To Satisfy Means-Plus-Function Structure Requirement

by McDermott Will & Emery

Triton Tech of Texas, LLC v. Nintendo of America, Inc.

Addressing whether a patent specification provided adequate specificity to satisfy indefiniteness scrutiny of a means-plus-function claim, the U.S. Court of Appeals for the Federal Circuit affirmed a district court’s finding that a means-plus-function term “integrator means” rendered asserted claims indefinite, finding that failure to identify corresponding algorithms for computer-implemented means-plus-function terms renders the claim indefinite.  Triton Tech of Texas, LLC v. Nintendo of America, Inc., Case No. 13-1476 (Fed. Cir., June 13, 2014) (Moore, J.).

Triton Tech of Texas (Triton) sued Nintendo of America, Inc. (Nintendo) alleging that the wildly successful Wii Remote infringed its patent directed to an input device for a whereby a user could manipulate an object that is represented graphically on a computer screen by moving the input device in three dimensions.

As claimed, the input device included sensors for detecting acceleration and rotation, as well as an integrator means for integrating the measurements by the sensors.  A “conventional microprocessor” is programmed to periodically read and numerically integrate the measurements by the motion sensors.  The patent did not disclose how numerical integration is performed, only that it is performed by a “conventional microprocessor.”

After the district court concluded that the means plus function “integrator means” rendered the asserted claims indefinite, Triton appealed.

Triton conceded that the integrator means structure was a conventional microprocessor, but argued that use of the phrase “numerical integration” was sufficient disclosure of the algorithm performed because the term was well known to those skilled in the art.  The Federal Circuit disagreed, explaining that numerical integration is not an algorithm but instead an entire class of different possible algorithms used to perform integration.  Consistent with the Federal Circuit’s ruling in Aristocrat (IP Update, Vol. 11, No. 4) and its progeny, if a function is performed by a general purpose computer or microprocessor, then the patent specification must also disclose the algorithm that the computer performs to accomplish that function.  The Court found that the failure to identity the corresponding algorithm for computer-implemented means-plus-function term renders the claim indefinite.

In distinguishing the disclosure in Triton’s patent from acceptable disclosures of an algorithm, the Federal Circuit clarified that “an algorithm can be expressed in many forms, including flow charts, a series of specific steps, mathematical formula, prose and so on.  However, merely using the term ‘numerical integration’ does not disclose an algorithm—i.e., a step-by-step procedure—for performing the claimed function.”  Moreover, the fact that a person of skill in the art may be able to discern an algorithm cannot save a claim from indefiniteness because a bare statement that known techniques or methods can be used does not disclose structure.

Triton tried to introduce (for the first time on appeal) a new argument supporting a two-step algorithm for the integration function. The Federal Circuit rejected this argument for its untimeliness.  Triton, the Court found, waived this argument by failing to raise it with the lower court.

DISCLAIMER: Because of the generality of this update, the information provided herein may not be applicable in all situations and should not be acted upon without specific legal advice based on particular situations.

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