The Court of Appeals for the Federal Circuit has now issued its decision in the case of In re Alappat, a case which achieved some notoriety when the Commissioner of Patents required reconsideration of an Appeal Board's decision to allow a patent before a separate and enlarged Appeal Board, including himself, which then held the subject matter to be unpatentable.

In its decision the Federal Circuit upheld the Commissioner's right to proceed in the way that he had. However, the court reversed the Board's decision on the substantive issue and upheld the patentability of a claim directed to: "A rasterizer for converting vector list data representing sample magnitudes of an input wave form into anti-aliased pixel illumination intensity data to be displayed on a display means" which comprised a series of elements defined purely in means form for determining certain features, normalizing such features and then out-putting the illumination intensity data in question.

The purpose of the invention was to provide a smooth wave form display in a digital oscilloscope. The essence of the Patent Office's rejection of the case had been that the means elements of the claims each simply recited a mathematical operation so that the combination of the steps in itself was a "mathematical algorithm for computing pixel information" and that "when the claim is viewed without the steps of this mathematical algorithm no other elements or steps are found".

This being the case, the enlarged Patent Office Appeal Board had found the invention lacking in statutory subject matter.

The Federal Circuit disagreed and concluded that what was being claimed was in fact a machine since the means in question had to have some physical embodiment (and since the decision In re Donaldson - see our June 1994 Newsletter (N.S. 183) - it was clear that means claims had to be construed so as to cover equivalents of what was actually disclosed in the specification). The court then, however, went on to consider the general question of the "mathematical algorithm" exception to patentability. While not denying the existence of such an exception, the court concluded that it must be read very narrowly. The court took the view that Congress had intended that "anything under the sun that is made by man" should be patentable and thus one should not read additional limitations into the statute. The limitations that existed were to be confined simply to those set out in the Supreme Court's decision in In re Diehr namely "laws of nature, natural phenomena and abstract ideas". Mathematical algorithms were only to be found to be unpatentable when they represented nothing more than an abstract idea. The court concluded that what was being claimed in the present case was:


The mere fact that the applicant himself had admitted that the claim covered a general purpose computer programmed to carry out the claimed invention did not alter this conclusion since once programmed to carry out the particular functions set out in the claim, "such programming creates a new machine because a general purpose computer in effect becomes a special purpose computer once it is programmed to perform particular functions pursuant to instructions from programmed software".

A strong dissent to the decision was registered by Chief Judge Archer on the ground that the holding was in effect opening the door to patentability of discoveries in mathematics, the scope of which would be repugnant to Congress's statutory scheme for the promotion of the useful arts.