In re Abele

• Citation: 684 F.2d 902
• Decision Date: 05 August 1982
• Docket Number: Appeal No. 81-618.
• Parties: In re Manlio Giacomo ABELE and Christopher Herbert Marshall.
• Court: United States Court of Customs and Patent Appeals

684 F.2d 902

In re Manlio Giacomo ABELE and Christopher Herbert Marshall.

Appeal No. 81-618.

United States Court of Customs and Patent Appeals.

August 5, 1982.

Jack E. Haken and Robert T. Mayer, Tarrytown, N. Y., for appellant.

Joseph F. Nakamura, Sol., and Jere W. Sears, Deputy Sol., Washington, D. C., for the Patent and Trademark Office.

Before MARKEY, Chief Judge, and RICH, BALDWIN, MILLER and NIES, Judges.

NIES, Judge.

This appeal is from the decision of the Patent and Trademark Office Board of Appeals (board) affirming the rejection of claims 5-7 and 33-47¹ in their application serial No. 850,892, filed November 15, 1977, for "Tomographic Scanner." The claims stand rejected under 35 U.S.C. § 101² as being drawn to nonstatutory subject matter. We affirm the rejection of claims 5 and 7 and reverse with respect to all remaining claims on appeal.

The Invention

Appellants' invention is in the field of image processing particularly as applied to computerized axial tomography or CAT scans. Specifically, appellants' invention is directed to an improvement in computed tomography whereby the exposure to X-ray is reduced while the reliability of the produced image is improved. Some understanding of tomography, both conventional and computed, is necessary as background for the subsequent analysis of the present invention.

Conventional tomography, also known as laminography, employs the simultaneous movement in opposite directions of an X-ray source and an X-ray film. The method produces a well-defined image of a plane through the body parallel to the plane of the X-ray film. In contrast to an ordinary X-ray, shadows of body structure which lie outside the plane of investigation are blurred so that they do not interfere with a focused image of the plane under investigation. Conventional tomographic systems are not practical when a visualized cross-section transverse to the body axis is desired. Computed tomography was developed to overcome this deficiency among others.

Basically, computed tomography provides an image representing a transverse slice of the body. This slicing is accomplished by rotating an X-ray source and a detection means around the perimeter of the section to be viewed. The source and detection means are placed 180° from each other to allow the detection means to measure the attenuation of the beam as it passes through the plane of interest. When enough measurements have been taken, a computer is implemented to mathematically interpret the data, which is then displayed as a reconstruction of the slice on, inter alia, a television screen for diagnostic purposes. Computed tomography is also useful for looking at only a section of a slice. Thus, if the plane of interest were in the abdomen region of a human, but only the liver were of concern, the computed tomography machine would act in the manner of a conventional tomograph and blur the images outside of this "Region of Interest." It has, however, been necessary that a spread of X-rays "S" be sufficiently wide to subtend the entire body in order to produce an image of the region of interest "R" by this blurring method, as illustrated by the following drawing:

Appellants have discovered that it is unnecessary to expose the body in the above fashion. Rather, they have discovered that the spread of X-ray, S, can be reduced so as to subtend only the region R thus:

Narrowing the beam is advantageous not only because the exposure of a body to X-ray is thereby reduced but also because computer calculation time to produce the image is shortened inasmuch as the amount of data to be processed is less. However, because fewer data can be collected due to the narrower beam, there is insufficient information to cancel out an object, n, such as a piece of rib, for example, which is in the beam bath. Thus, the resultant image shows the region R with an artifact³ appearing therein due to that object, n:

Appellants' invention is directed to an improvement in CAT scan imaging technique whereby the body is exposed to less radiation and, through use of a weighting function in the calculations producing the image, the artifacts are eliminated.

The Rejection

The examiner rejected the claims on appeal under the authority of Parker v. Flook, 437 U.S. 584, 98 S.Ct. 2522, 57 L.Ed.2d 451 (1978). In the final rejection and in the examiner's answer before the board, the examiner construed Flook as mandating the following test:

Taking each claim as a whole, it is assumed, for analysis purposes only, that any mathematical calculation in the claim is part of the prior art. If what is left is new and unobvious, then the claim, taken as a whole, protects more than a mathematical calculation and it is deemed statutory. But if the remainder of the claim is not novel nor unobvious, then the claim, taken as a whole, merely seeks to protect the mathematical calculation and, as such, does not comprise statutory subject matter.

Applying the above test, the examiner determined that, apart from the mathematical calculations, the remaining steps were well known or were "merely a necessary antecedent step to provide values for solving the mathematical equations," and, thus, were directed to nonstatutory subject matter, citing In re Richman, 563 F.2d 1026, 195 USPQ 340 (Cust. & Pat.App.1977).

The Board's Decision

The board did not address the examiner's contentions, relying instead on In re Freeman, 573 F.2d 1237, 197 USPQ 464 (CCPA 1978), as modified by In re Walter, 618 F.2d 758, 205 USPQ 397 (Cust. & Pat.App.1980). Without resort to detailed claim language, the board affirmed the rejection under 35 U.S.C. § 101 as follows:

When the claims are analyzed in the manner dictated by Walter, it is manifest that the mathematical algorithm is not implemented in a manner to define structural relationships between physical elements in the apparatus claims or to refine or limit claim steps in the process claims. The claims do no more than present and solve a mathematical algorithm and are manifestly nonstatutory.

One member dissented with respect to rejection of claims 6 and 33-47 concluding that these claims are directed to "producing a product, an improved tomographic X-ray image," and are, therefore, directed to statutory subject matter citing Diamond v. Diehr, 450 U.S. 175, 101 S.Ct. 1048, 67 L.Ed.2d 155 (1981).

OPINION

I

A

We agree with the board that a two-part analysis⁴ is the proper vehicle for resolution of issues here presented under 35 U.S.C. § 101. However, we agree with appellants that the second step of the analysis is not as limited as the board held it to be.

B

In Gottschalk v. Benson, 409 U.S. 63, 93 S.Ct. 253, 34 L.Ed.2d 273 (1972), the Supreme Court concluded that claims directed to a particular "algorithm," conversion of binary coded decimal numbers to binary numbers, did not define patentable subject matter. In that case the Court defined the term "algorithm" as "a procedure for solving a given type of mathematical problem." Id. at 65, 93 S.Ct. at 254. The Court's holding in Benson became the basis for the first part of the two-part analysis set forth by this court in In re Freeman, 573 F.2d 1237, 197 USPQ 464 (Cust. & Pat.App.1978).

In Freeman, 573 F.2d at 1245, 197 USPQ at 470, this court concluded:

As a bare minimum, application of Benson in a particular case requires a careful analysis of the claims, to determine whether, as in Benson, they recite a "procedure for solving a given type of mathematical problem." Citation omitted. Emphasis in original.

Hence, the first part of the analysis requires:

First, it must be determined whether the claim directly or indirectly recites an "algorithm" in the Benson sense of that term .... Id. at 1245, 197 USPQ at 471.

The second part of the Freeman analysis is derived from the further holding in Benson, 409 U.S. at 72, 93 S.Ct. at 257, that any patent issued in that case "would wholly pre-empt the mathematical formula and in practical effect would be a patent on the algorithm itself." Thus, it was concluded that the presence of an "algorithm" in a claim would not render a claimed invention nonstatutory unless the invention claimed only the "algorithm." Stating this conclusion in the language of Benson, this court declared:

Second, the claim must be further analyzed to ascertain whether in its entirety it wholly preempts that algorithm. Freeman, Id. at 1245, 197 USPQ at 471.

This latter step in the Freeman analysis was not reached because of this court's conclusion that the claims did not recite an "algorithm." In In re Toma, 575 F.2d 872, 197 USPQ 852 (Cust. & Pat.App.1978), the same test was discussed but, again, the second part of the analysis was not reached. Subsequently, the Supreme Court handed down its decision in Parker v. Flook, 437 U.S. 584, 98 S.Ct. 2522, 57 L.Ed.2d 451 (1978), making clear that the second part of the above analysis was erroneous. The Court held that the claim need "not ... cover every conceivable application of the formula" to be nonstatutory. Id. at 586, 98 S.Ct. at 2523.

In sum, the Court's decisions have made clear that a claim does not present patentable subject matter if it would wholly preempt an algorithm, Benson, supra, or if it would preempt the algorithm but for limiting its use to a particular technological environment, Flook, supra. However, these decisions leave undefined what does constitute statutory subject matter.

In In re Johnson, 589 F.2d 1070, 1075, 200 USPQ 199, 205 (Cust. & Pat.App.1978), this court held that, while reciting an algorithm, the claims did not merely define a method of solving a mathematical equation because

any calculations which may be performed in practicing the process ... are but a part of the process which includes the other recited steps.

... They are incident to producing a noise-free signal trace from a reference trace. Id. at 1080, 200 USPQ at 209 (emphasis added).

This conclusion rests on the premise that an otherwise statutory...