In re Warmerdam, 1994

Warmerdam’s patent application was directed to a method and apparatus for controlling the motion robotic machines to avoid collisions.

The technique required determining the shape and position of the edges of the objects to be avoided. The prior art taught that collision avoidance operations could be simplified by assuming that the objects were larger and more regularly shaped than they actually were. This could be done by treating the object as if it were a circle or sphere (called a “bubble”) of sufficient size to enclose the object, and by assuming that any motion that impinged upon the circle would have produced a collision. Appellants’ invention claimed a further refinement of prior art bubble systems. The positions of objects were determined by measuring the locations of artificial circular boundaries, but the measurement process did not end if the machine determines that the circular boundary will be violated in a potential collision. Instead, if a potential collision was detected, appellants further refined the determination of the boundary position by replacing the spherical bubble zone with a set of smaller, more refined bubble zones. Appellants referred to their set of increasingly better defined safety zones as a bubble hierarchy. Warmerdam conceded that the use of bubble hierarchies for collision avoidance was known. The asserted novelty of Warmerdam’s method and apparatus was the generation and placement of the hierarchy of bubbles along the medial axis of the object. The medial axis of an object was defined in the specification to be a line with the same topology as the object itself connecting points which lay midway between boundary centers of the object.

As filed, the application contained seven claims of which only claims 1-6 were at issue in the case. The other claim, claim 7, was indicated by the examiner as allowable. Claims 1-4 were method claims, of which claim 1 was the sole independent claim:
1. A method for generating a data structure which represents the shape of [sic] physical object in a position and/or motion control machine as a hierarchy of bubbles, comprising the steps of:
first locating the medial axis of the object and
then creating a hierarchy of bubbles on the medial axis.

Claim 5 was directed to a machine:
5. A machine having a memory which contains data representing a bubble hierarchy generated by the method of any of Claims 1 through 4.

Claim 6 was directed to a data structure:
6. A data structure generated by the method of any of Claims 1 through 4.

The Federal Circuit noted that the statute equates the term “method” with the term “process,” see 35 U.S.C. Section 100(b), the question becomes what is it that this process does, and in doing it is it other than what the Supreme Court must have understood to be “laws of nature, natural phenomena or abstract ideas”?

The Board concluded that each of the two steps recited in claim 1, involved the solving of a mathematical algorithm. The Commissioner asserted that these conclusions are sustainable on the ground that the preferred method of locating a medial axis identified in the specification was a mathematical procedure known as Hilditch Skeletonization method, and on the ground that the top-down and bottom-up procedures identified in the specification (and claimed in the dependent claims) for creating the bubble hierarchy were likewise mathematical in nature. The Commissioner also pointed to several cases3 in which process steps similar to those recited in claims 1-4, i.e., steps such as computing, determining, cross-correlating, comparing, selecting, initializing, testing, modifying, and identifying, were found to implicitly recite the solving of a mathematical algorithm.

Warmerdam, by contrast, argued that the claims were broad enough to cover methods which involve physically measuring the contour of the object. Thus, according to Warmerdam, the claims did not essentially recite a mathematical algorithm, but only incidentally do so.

The Federal Circuit agreed, and stated that Claim 1 was broad enough to cover methods for locating the medial axis of an object that include physically measuring the contour of the object with a ruler or simply by eyeballing the object, and then creating the bubble hierarchy by manually drawing it. In that sense, it did not necessarily recite the solving of a mathematical algorithm. The fact that the claim covered methods which are essentially mathematical in nature, as discussed infra, is not dispositive. Claims should be evaluated by their limitations, not by what they incidentally cover.

On the other hand, the preferred, and the only practical, embodiment of the claimed method involves steps which are essentially mathematical in nature, i.e., utilization of the Hilditch Skeletonization method to locate the medial axis, followed by utilization of a top-down or bottom-up procedure for creating the bubble hierarchy. In this sense, at least, the claim is mathematical in nature.

The Federal Circuit declined to resolve the issue of the definition of “mathematical algorithm,” because they found that regardless whether the claim can be said to recite indirectly or directly a mathematical algorithm, the dispositive issue for assessing compliance with Section 101 in this case is whether the claim is for a process that goes beyond simply manipulating “abstract ideas” or “natural phenomena.”

The Federal Circuit noted that claim 1 recited the steps of “locating” a medial axis, and “creating” a bubble hierarchy and concluded that these steps described nothing more than the manipulation of basic mathematical constructs, the paradigmatic “abstract idea” and noted that, as the Supreme Court has made clear, [a]n idea of itself is not patentable, Rubber-Tip Pencil Co. v. Howard, 20 U.S. (1 Wall.) 498, 507 (1874); taking several abstract ideas and manipulating them together adds nothing to the basic equation.

Warmerdam’s argument that the claim implies physically measuring the contour of an object missed the point. As a whole, the claim involved no more than the manipulation of abstract ideas. Moreover, from the standpoint of Section 101, a physical measurement step is indistinguishable from the data gathering step which, as was held in In re Grams, 888 F.2d 835, 12 USPQ2d 1824 (Fed. Cir. 1989), was insufficient, standing alone, to impart patentability to a claim.

Warmerdam’s other argument, that the manipulation of data as described in the claims constitutes or represents a sufficient level of physical activity to impart patentability to the claim, was not convincing. The problem with Warmerdam’s argument was that the claims here did not have the effect of requiring more than the manipulation of ideas. The Federal Circuit thus concluded that the Board did not err in sustaining the rejection of claims 1-4 under Section 101.

The Federal Circuit then noted that Claim 5 was for a machine, and was clearly patentable subject matter. The Board denied patentability on the grounds it was indefinite under 35 U.S.C. Section 112, second paragraph and was not in conventional product-by-process format, and the Commissioner repeated this assertion. Warmerdam argued that claim 5 conforms to the conventional product- by-process format, and thus is definite. The Commissioner argued that it was unclear how a memory is produced by the steps recited in claims 1-4. Second, the Commissioner argued that the bubble hierarchy which was created in the recited steps was not an exact, well-defined data structure.

The Federal Circuit noted that the legal standard for definiteness is whether a claim reasonably apprises those of skill in the art of its scope, and then concluded that
Claim 5 satisfies this test. It covers any machine (presumably including a known computer) having a memory which contains any data representing a bubble hierarchy determined by any of the methods of claims 1-4. The Federal Circuit stated that there is no requirement that a claim for a machine which incorporates process steps, such as claim 5, must conform to the conventional definition of a product-by-process claim.

The Federal Circuit stated that the ideas expressed in claims 1 through 4 are well known mathematical constructs, and lend themselves to manipulation through known computer technology. There was no showing that one skilled in the art would have had any particular difficulty in determining whether a machine having a memory containing data representing a bubble hierarchy was or was not within the scope of claim 5. The Board’s point, that the claim leaves unclear the technique of how the memory was configured with the data, had no bearing on this issue. The claim plainly covered all such techniques. The Federal Circuit concluded the Board erred in sustaining the rejection of claim 5 for indefiniteness.

The Court then concluded that the data structure claim was non-statutory. Warmerdam argued that a data structure was one of the categories of patentable subject matter recited in Section 101, and thus that the Board erred in sustaining the rejection of claim 6 under Section 101. The Commissioner, by contrast, citing Kewanee Oil Co. v. Bicron Corp., 416 U.S. 470 (1974), argued that the rejection should be sustained because the claim is not one of the categories of subject matter recited in Section 101, to wit, a process, machine, manufacture, composition of matter, or an improvement thereof. The Federal Circuit agreed with the Commissioner. In the IEEE Standard Computer Dictionary (1991), the phrase “data structure” is defined as [a] physical or logical relationship among data elements, designed to support specific data manipulation functions. Since the “data structure” of claim 6 was nothing more than another way of describing the manipulation of ideas contained in claims 1-4, it suffered from the same fatal defect they did, according to the Federal Circuit.