In a precedential decision, Ex parte Rodriguez1, the BPAI of the United States Patent and Trademark Office (USPTO), applying a recent Federal Circuit decision, Aristocrat Techs. Austl. Pty Ltd. v. Inter. Game Tech.2, held that if a claim directed to a computer is determined to invoke 35 USC §112, sixth paragraph3, the specification must not only disclose a general-purpose computer, but must also disclose a corresponding algorithm, in order to provide the requisite disclosure of structure. This article explores the reasoning of Rodriguez, and identifies strategies for drafting patent applications related to computer-implemented inventions in light of Rodriguez.

In Rodriguez, the BPAI entered new grounds of rejection against the appellant’s pending claims, including a new rejection of the apparatus claims4 under 35 USC §112, second paragraph5 as being indefinite. The BPAI provided two separate analyses of the apparatus claims: an analysis of independent claim 10, which recited an apparatus comprising four means plus function elements, and an analysis of independent claim 1, which recited an apparatus comprising a system configuration generator, a system builder and a simulation verification environment. Although providing two separate analyses, the BPAI made clear that the basis for each rejection under 35 USC §112, second paragraph was the same: the Aristocrat holding.

In Aristocrat, the Federal Circuit held Aristocrat’s claim6 invalid for indefiniteness for failing to describe sufficient structure as required by 35 USC §112, sixth paragraph. The court found Aristocrat’s claim, including a “game control means,” to be a means-plus-function claim directed to a computer-implemented invention, which performed three functions: (1) to control images displayed on the display means; (2) to pay a prize when a predetermined combination of symbols matches the symbol positions selected by the player; and (3) to define the pay lines for the game according to each possible combination of the selected symbol positions. The court further found that the only portion of Aristocrat’s specification that described the structure corresponding to the three functions performed by the “game control means” was a statement that it was within the capability of a worker in the art to introduce the methodology on any standard microprocessor-based gaming machine by means of appropriate programming.

In characterizing computer-implemented inventions, the court in Aristocrat stated that a general purpose computer must be programmed by a specific algorithm because it becomes a special purpose computer capable of carrying out a specific function. Because a general purpose computer requires a specific algorithm before being capable of carrying out a specific function, the court determined that in a means-plus-function claim in which the disclosed structure is a computer or microprocessor programmed to carry out a specific algorithm, the disclosed structure is not the general purpose computer, but rather the special purpose computer programmed to perform the disclosed algorithm. Thus, the court held, in cases involving a computer-implemented invention in which an inventor has invoked means-plus-function claiming, the structure disclosed in the specification must be more than simply a general purpose computer or microprocessor. Because Aristocrat’s specification did not disclose a specific algorithm that could transform a standard microprocessor into a special purpose computer capable of carrying out the three functions performed by the “control means,” the court held that the specification failed to describe sufficient structure as required by 35 USC §112, sixth paragraph.

Applying Aristocrat, the BPAI in Rodriguez found that claim 10 was a means-plus-function apparatus claim invoking 35 USC §112, sixth paragraph, due to its use of “means” in the claim and the lack of recitation of structure to perform the functions of building a system level netlist, generating system parameters, verifying the system and providing automatic random verification. The BPAI further found that the appellant’s specification generally described a system which provided automated random verification of complex and structurally variable systems, but did not disclose an algorithm by which the system was able to perform the functions recited in claim 10. Thus, the BPAI held that claim 10 was indefinite because the specification failed to adequately describe sufficient structure for performing the functions recited in the “means” elements so as to render the claim definite.

The BPAI then turned to apparatus claim 1. Despite the lack of “means” in the claim, the BPAI still found it was a means-plus-function apparatus claim invoking 35 USC §112, sixth paragraph. The BPAI indicated the absence of the term “means” in a claim does not necessary negate invocation of 35 USC §112, sixth paragraph, but merely triggers a rebuttable presumption that 35 USC §112, sixth paragraph does not apply. However, the presumption can be rebutted by showing that the claim element recites a function without reciting sufficient structure for performing the function.7 The BPAI found that the structural elements of this claim included a “system configuration generator,” a “system builder” and a “simulation verification environment,” which are not art-recognized structures for performing the claimed functions. Based on these findings, the BPAI determined that these claim elements were verbal constructs that were not recognized as the name of a structure, that the claim elements were merely substitutes for the term "means for” and that claim 1 invoked 35 USC §112, sixth paragraph.8 It then applied Aristocrat to hold that claim 1 was indefinite because it failed to adequately describe sufficient structure for performing the functions recited in the elements of the claim so as to render it definite.

Rodriguez expands the reach of Aristocrat to apparatus claims directed to computer-implemented inventions that do not use the term “means.” Because the BPAI’s decision uses rather arbitrary reasoning in determining that a claim invokes 35 USC §112, sixth paragraph, despite the absence of “means,” a patent drafter cannot be sure that an apparatus claim will not be construed as a means-plus-function claim. Thus, there are two strategies a patent drafter can implement to avoid an indefinite rejection based on Aristocrat. The first is to clearly disclose the structure of the general purpose computer or microprocessor that the software is performed on in the specification, and to make sure that the disclosed structure is clearly recited in the claim. The second is to disclose at least one algorithm in the specification that performs the function recited in the claim. Such an algorithm may take the form of process steps illustrated in a flow chart, a sequence diagram or pseudo code. In conclusion, Rodriguez will require patent drafters to carefully scrutinize their disclosure and claims directed to computer-implemented inventions.