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Archived updates for Monday, March 31, 2008

"Control Means" Support Requires Algorithm to Transform Disclosed General Puprose Computer to Special Purpose Computer

In Aristocrat Tech. Australia PTY Limited v. International Game Tech. (march 28, 2008), the Federal Circuit affirmed that the patent’s disclosure of a general purpose, programmable microprocessor was not a sufficient disclosure of structure to satisfy section 112 paragraph 6 with regard to the "game control means" or "control means" in claim 1 of U.S. Patent No.
6,093,102
for a gaming machine.

According to Circuit Judge Bryson,


. . . Aristocrat also argues that, even if there is no disclosure of an algorithm in the patent, the disclosure of a microprocessor with "appropriate programming" is a sufficient disclosure of structure for means-plus-function purposes, because the evidence showed that one of ordinary skill in the art could build the device claimed in the ’102 patent based on the disclosure in the specification. That argument, however, conflates the requirement of enablement under section 112 paragraph 1 and the requirement to disclose the structure that performs the claimed function under section 112 paragraph 6.

Although the examples given in the ’102 patent might enable one of ordinary skill to make and use the invention, they do not recite the particular structure that performs the function and to which the means-plus-function claim is necessarily limited.
Whether the disclosure would enable one of ordinary skill in the art to make and use the invention is not at issue here. Instead, the pertinent question in this case is whether Aristocrat’s patent discloses structure that is used to perform the claimed function. Enablement of a device requires only the disclosure of sufficient information so that a person of ordinary skill in the art could make and use the device. A section 112 paragraph 6 disclosure, however, serves the very different purpose of limiting the scope of the claim to the particular structure disclosed, together with equivalents. The difference between the two is made clear by an exchange at oral argument. In response to a question from the court, Aristocrat’s counsel contended that, in light of the breadth of the disclosure in the specification, any microprocessor, regardless of how it was programmed, would infringe claim 1 if it performed the claimed functions recited in the means-plus-function limitations of that claim. That response reveals that Aristocrat is in essence arguing for pure functional claiming as long as the function is performed by a general purpose computer. This court’s cases flatly reject that position.

. . . Aristocrat was not required to produce a listing of source code or a highly detailed description of the algorithm to be used to achieve the claimed functions in order to satisfy 35 U.S.C. § 112 ¶ 6. It was required, however, to at least disclose the algorithm that transforms the general purpose microprocessor to a "special purpose
computer programmed to perform the disclosed algorithm." WMS Gaming, 184 F.3d at 1349. Because the district court correctly held that was not done in this case, we uphold the judgment of the district court.

* * *

In this case, Aristocrat acknowledges that the only portion of the specification that describes the structure corresponding to the three functions performed by the "control means" is the statement that it is within the capability of a worker in the art "to introduce the methodology on any standard microprocessor base [sic] gaming machine by means of appropriate programming." ’102 patent, col. 3, ll. 2-4. That description goes no farther than saying that the claimed functions are performed by a general purpose computer. The reference to "appropriate programming" imposes no limitation whatever, as any general purpose computer must be programmed. The term "appropriate programming" simply references a computer that is programmed so that it performs the function in question, which is to say that the function is performed by a computer that is capable of performing the function.

Aristocrat offers two responses to the district court’s conclusion that the patent did not disclose sufficient structure. First, Aristocrat argues that the specification disclosed algorithms that were sufficient to constitute a qualifying disclosure of structure. Second, Aristocrat argues that no disclosure of specific algorithms was necessary in any event.

As to the first argument, Aristocrat contends that the language of claim 1 referring to "the game control means being arranged to pay a prize when a predetermined combination of symbols is displayed in a predetermined arrangement of symbol positions selected by a player" implicitly discloses an algorithm for the
microprocessor. That is, when the winning combination of symbols is displayed, the program should pay a prize. But that language simply describes the function to be performed, not the algorithm by which it is performed. Aristocrat’s real point is that devising an algorithm to perform that function would be within the capability of one of skill in the art, and therefore it was not necessary for the patent to designate any particular algorithm to perform the claimed function. As we have noted above, however, that argument is contrary to this court’s law.

Aristocrat also points to language in claim 1 that, according to Aristocrat, "sets forth the mathematical equation that describes the result of practicing the third function." The language in question recites "defining a set of predetermined arrangements for a current game comprising each possible combination of the symbol position selected by the player which have one and only one symbol position in each column of the display means." The problem with Aristocrat’s argument is underscored by Aristocrat’s very characterization of the role of the equation: It describes the result of practicing the third function. That is, the equation is not an algorithm that describes how the function is performed, but is merely a mathematical expression that describes the outcome of performing the function. To be sure, as Aristocrat argues, the equation "restricts ‘appropriate programming’ to algorithms which result in the specified number of winning opportunities." But that argument simply concedes that the equation describes an outcome, not a means for achieving that outcome. The equation thus does not disclose the structure of the claimed device, but is only another way of describing the claimed function.

Finally, Aristocrat contends that "the written description delineates what constitutes ‘appropriate programming’ through the disclosed embodiments of the invention." Again, however, the description of the embodiments is simply a description of the outcome of the claimed functions, not a description of the structure, i.e., the computer programmed to execute a particular algorithm.


As noted by Professor Crouch,
The algorithm missing from ATA’s disclosure is almost certainly within the ability of an ordinary game programmer. In fact, I believe that it would only take me (a law professor) only a few hours to create a rough algorithm showing how the ATA software program could operate. Judge Bryson shot-down that argument: “Structure for a means-plus-function element must be provided in the specification regardless of whether the structure is already well known in the art.”

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