Aрplicants Ralph A. Grams and Dennis C. Lezotte (Grams) appeal from the decision of the Board of Patent Appeals and Interferences (Board), United States Patent and Trademark Office, Appeal No. 88-1391 (December 28, 1988), affirming the examiner’s rejection of claims 1 and 3-16, which constitute all the claims remaining in Application S.N. 625,247, filed June 27, 1984. The claims were rejected under 35 U.S.C. § 101 as being directed to nonstatutory subject matter because they in essence claim either a mathematical algorithm or a method of doing business. We affirm.
BACKGROUND
The invention provides a method of testing a complex system to determine whether the system condition is normal or abnormal and, if it is abnormal, to determine the cause of the abnormality. As disclosed in the specification, the invention is applicable to any complex system, whether it be electrical, mechanical, chemical, biological, or combinations thereof. The system comprises a plurality of constituent subsystems or parts, some characteristic оf which is represented by a set of correlated parameters susceptible of measurement and representative of the overall system. The disclosed invention involves considering the entire set of parameters, diagnosing the existence of an abnormality, and identifying which particular parameters of the set are rеsponsible for the abnormality.
The claims limit the disclosed invention to the diagnosis of an individual. Claim 1, on which the other claims depend, reads:
1. A method of diagnosing an abnormal condition in an individual, the individual being characterized by a plurality of correlated parameters of a set of such parameters that is representative оf the individual’s condition, the parameters comprising data resulting from a plurality of clinical laboratory tests which measure the levels of chemical and biological constituents of the individaul [sic] and each parameter having a reference range of values, the method comprising [a] performing said plurality of clinical laboratory tests оn the individual to measure the values of the set of parameters; [b] producing from the set of measured parameter values and the reference ranges of values a first quantity representative of the condition of the individual; [c] comparing the first quantity to a first predetermined value to determine whether the individual’s condition is abnormal; [d] upon determining from said comparing that the individual’s condition is abnormal, successively testing a plurality of different combinations of the constituents of the individual by eliminating parameters from the set to form subsets corresponding to said combinations, pro- *837 dueing for each subset a second quantity, and comparing said second quantity with a sеcond predetermined value to detect a non-significant deviation from a normal condition; and [e] identifying as a result of said testing a complementary subset of parameters corresponding to a combination of constituents responsible for the abnormal condition, said complementary subset comprising the parameters eliminated from the set so as to produce a subset having said non-significant deviation from a normal condition.
(Emphasis and bracketed letters added.) Thus, step [a] requires the performance of clinical laboratory tests on an individual to obtain data for the parameters
{e.g.,
sodium content). The remaining steps, [b]-[e], analyzе that data to ascertain the existence and identity of an abnormality, and possible causes thereof. In that regard, steps [b]-[e] are in essence a mathematical algorithm, in that they represent “[a] procedure for solving a given type of mathematical problem.”
Gottschalk v. Benson,
Applicants do not dispute that claim 1 includes a mathematical algorithm. However, they contend that the mere recital of an algorithm does not automatically render a claim nonstatutory. They are correct in that regard, but the inclusion of a mathematical algorithm in a claim can render it nonstatutory if the claim in essence covers only the algorithm. The Board held that was the case here.
ISSUE
Whether the algorithm-containing claims at issue are drawn to statutory subject matter.
OPINION
Section 101 of Title 35 states:
Whoever invents or discovers any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof, may obtain a patent therefor, subject to the conditions and requirements of this title.
(Emphasis added.) Intuitively, one might conclude that the statute’s “any ... process” would include the diagnostic method clаimed by applicants. Indeed, even without physical step [a] present in the claims, application of the algorithm in steps [b]-[e] seems to be a type of “process”. The Supreme Court recognized as much in
Parker v. Flook,
Flook
makes clear, however, as did its forerunner,
Gottschalk v. Benson,
Construing section 101 as excluding mathematical algorithms seems somewhat at odds with the liberal view of that section expressed in a more recent Supreme Court opinion,
Diamond v. Chakrabarty,
Chakrabarty
expressly rejects the argument that patentability in a new area, “micro-organisms[,] cannot qualify as patentable subject matter until Congress expressly authorizes such protection.”
Id.
at 314-15,
Another recent case,
Diamond v. Diehr,
Notwithstanding those statements in
Diehr
and
Chakrabarty, Benson
remains the law. Indeed,
Benson
is cited in both
Diehr
and
Chakrabarty,
with no apparent attempt in either opinion to overrule or disapprove of it. Thus, “an algorithm, or mathematical formula ... like a law of nature ... cannot be the subject of a patent.”
Diamond v. Diehr,
On the other hand, “the mere presence of a mathematical exercise, as a step or steps in a process involving nonmathematieal steps, should not slam the door of the Patent and Trademark Office upon an applicant[.]”
In re Sarkar,
Once a mathematical algorithm has been found, the claim as a whole must be further analyzed. If it appears that the mathematical algorithm is implemented in a specific manner to define structural relationships between the physical elements of the claim (in apparatus claims) or to refine or limit claim steps (in prоcess claims), the claim being otherwise statutory, the claim passes muster under § 101.
Id.
at 767,
The
Walter
test, of deciding whether the algorithm “define[s] structural relationships” or “refine[s] or limit[s] claim steps” in an otherwise statutory claim,
*839
“was not intended to be the exclusive test for determining the presence of statutory subject matter.”
In re Meyer,
provided that its application is circumscribed by more than a field of use limitation or non-essentiаl post-solution activity. Thus, if the claim would be “otherwise statutory,” albeit inoperative or less useful without the algorithm, the claim likewise presents statutory subject matter when the algorithm is included.[ 4 ]
Id.
(citation omitted). In all instances, this critical question must be answered: “What did applicants invent?”
Id.
at 907,
[e]ach invention must be evaluated as claimed: yet semаntogenic considerations preclude a determination based solely on words appearing in the claims. In the final analysis under § 101, the claimed invention, as a whole, must be evaluated for what it is.
Hence, the analysis requires careful interpretation of each claim in light of its supporting disclosure.
Id.
(citation omitted).
See also Diamond v. Diehr,
Though that analysis can be difficult, it is facilitated somewhat if, as here, the only physical step involves merely gathering data for the algorithm. As stated in
In re Christensen,
Given that the method of solving a mathematical equation may not be the subject of patent protection, it follows that the addition of the old and necessary antecedent steps of establishing values for the variables in thе equation cannot convert the unpatentable method to patentable subject matter. 5
Accord In re Chatfield,
*839 No mathematical equation can be used, as a practical matter, without establishing and substituting values for the variables expressed therein. Substitution of values dictated by the formula has thus been viewed as a form of mathematical step. If the steps of gathering and substituting values were alone sufficient, every mathematical equation, formula, or algorithm having any practical use would be per se subject to patenting as a “process” under § 101. Consideration of whether the substitution of specific values is enough to convert the disembodied ideas present in the formula into an embodiment of those ideas, or into an application of the formula, is foreclosed by the current state of the law.
*840 Whether section 101 precludes patenta-bility in every case where the physical step of obtaining data for the algorithm is the only other significant elemеnt in mathematical algorithm-containing claims is a question we need not answer. Analysis in that area depends on the claims as a whole and the circumstances of each case. Rather, we address only the claims and other circumstances involved here.
The sole physical process step in Grams’ claim 1 is step [a], i.e., pеrforming clinical tests on individuals to obtain data. The specification does not bulge with disclosure on those tests. To the contrary, it focuses on the algorithm itself, although it briefly refers to, without describing, the clinical tests that provide data. Thus, it states: “The [computer] program was written to analyze the results of up to eighteen clinical labоratory tests produced by a standard chemical analyzer that measures the levels of the chemical biological components listed....” The specification also states that “[t]he invention is applicable to any complex system, whether it be electrical, mechanical, chemical or biological, or сombinations thereof.” From the specification and the claim, it is clear to us that applicants are, in essence, claiming the mathematical algorithm, which they cannot do under Gottschalk v. Benson. The presence of a physical step in the claim to derive data for the algorithm will not render the claim statutory.
Applicants argue that
In re Abele,
Allowed claim 6 in
Abele
required operation оf an algorithm on x-ray attenuation data, with a subsequent display. The data were available for the algorithm only after the production and detection steps,
i.e.,
after an x-ray beam was passed through an object using a CAT scanner, and detected upon exit. The court concluded that in the absence of the algorithm, “the production, detection, and display steps would still be present and would result in a conventional CAT-scan process.”
In Abele, therefore, the algorithm served to improve the CAT-scan process. As such, the algorithm satisfied the Walter guideline of “refining a process step in a process that is otherwise statutory,” and hence, it presented statutory subject matter. In this case, because algorithm steps [b]-[e] do not operate to change any aspect of the physical process of step [a], the claim does not satisfy the Walter guideline. Though this by itself is not dispositive (see discussion of Walter, su-pra), patentability here is precluded by the fact that physical step [a] merely provides data for the algorithm.
The claim here is more like those in
In re Meyer,
Thus, claim 1 is unpatentable. Claims 3-15 were not argued separately from claim 1; hence they fall with our treatment of that claim.
See, e.g., Environmental Instruments, Inc. v. Sutron Corp.,
Because we affirm the Board’s holding that the applicants’ claims are unpatentable under section 101 as being drawn to a nonstatutory mathematical аlgorithm, we need not address the issue of whether they are also unpatentable as a method of doing business.
AFFIRMED.
Notes
. It is of no moment that the algorithm is not expressed in terms of a mathematical formula. Words used in a claim operating on data to solve a problem can serve the same purpose as a formula.
See, e.g., In re Freeman,
. The Court recognized that Congress’ authority to regulate exclusive rights to inventions "is exercised in the hope that '[t]he productive effort thereby fostered will have a positive effect on society through the introduction of new products and processes of manufacture into the economy, and the emanations by way of increased employment and better lives for our citizens.’”
Chakrabarty,
. See also D. Chisum, The Patentability of Algorithms, 47 U.Pitt.L.Rev. 959 (1986). Professor Chisum suggests that Chakrabarty turned around the burden of proof on why something should be included or excluded in the patent system, given that it meets the apparent statutory requirements. Id. at 1011 — 12. Chakrabarty suggests, he concludes, that the opponents of patent protection for algorithms bear the burden of showing that such protection should be excluded frоm the typical protection available for other forms of intellectual property. Id. at 1011.
. We do not read the last sentence of this quote as declaring patentable any claim that is statutory without the algorithm. We read it consistently with the previous sentence, and with
Walter,
as requiring (to meet the
Walter
test) not only that the physical steps in the claim (without the algorithm) сonstitute a statutory process but, also, that the algorithm operates on a claimed physical step.
Accord In re Meyer,
. One commentator interprets
In re Taner,
