Court Opinion

ID: 9482708
Source: CourtListenerOpinion
Date Created: 2023-08-05 08:58:24.297008+00
Date Added: 2024-06-11T17:49:09.500754
License: Public Domain

RADER, Circuit Judge,
concurring.
Nearly twenty years ago, in Gottschalk v. Benson, 409 U.S. 63, 93 S.Ct. 253, 34 L.Ed.2d 273 (1972), the Supreme Court dealt with a computer process for conversion of binary coded decimals into pure binary numbers. Benson held this mathematical algorithm ineligible for patent protection. 409 U.S. at 65, 71-72, 93 S.Ct. at 254, 257. Because computer programs rely heavily on mathematical algorithms, commentators saw dire implications in the Supreme Court’s opinion for patent protection of computer software. For instance, one treatise, citing Benson, stated:
[A] recent Supreme Court decision seemingly eliminated patent protection for computer software.
Donald S. Chisum, Patents § 1.01 (1991); see also id. at § 1.03[6].
The court upholds the ’459 patent by applying a permutation of the Benson algorithm rule. In reaching this result, the court adds another cord to the twisted knot of precedent encircling and confining the Benson rule. While fully concurring in the court’s result and commending its ability to trace legal strands through the tangle of post-Benson caselaw, I read later Supreme Court opinions to have cut the Gordian knot. The Supreme Court cut the knot by strictly limiting Benson.
Relying on the language of the patent statute, the Supreme Court in Diamond v. Diehr, 450 U.S. 175, 101 S.Ct. 1048, 67 L.Ed.2d 155 (1981), turned away from the Benson algorithm rule. Thus, I too conclude that the ’459 patent claims patentable subject matter — not on the basis of a two-step post-Benson test, but on the basis of the patentable subject matter standards in title 35. Rather than perpetuate a nonstat-utory standard, I would find that the subject matter of the ’459 patent satisfies the statutory standards of the Patent Act.
I.
The questions presented by this case are whether the ’459 patent claims a process and apparatus within the meaning of 35 U.S.C. § 101 (1988). Section 101 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.
According to this language, “any” invention or discovery within the four broad categories of “process, machine, manufacture, or composition of matter” is eligible for patent protection. “Any” is an expansive modifier which broadens the sweep of the categories. See Diamond v. Chakrabarty, 447 U.S. 303, 308-09, 100 S.Ct. 2204, 2207, 65 L.Ed.2d 144 (1980). The language of section 101 conveys no implication that the Act extends patent protection to some subcategories of machines or processes and not to others.
The limits on patentable subject matter within section 101 focus not on subcategories of machines or processes, but on characteristics, such as newness and usefulness. Section 101 also specifies that, in addition to newness and usefulness, an invention or discovery must satisfy other “conditions and requirements.” These other “conditions and requirements” encom*1062pass characteristics like nonobviousness under 35 U.S.C. § 103 (1988), or requirements like those in 35 U.S.C. § 112 (1988). In other words, the language of the Patent Act does not suggest that the words “machine” or “process” carry limitations outside their ordinary meaning. See Diehr, 450 U.S. at 182, 101 S.Ct. at 1054 (“Unless otherwise defined, ‘words will be interpreted as taking their ordinary, contemporary, common meaning.’ ”). Rather the Act, by its terms, extends patent protection to “any” machine or process which satisfies the other conditions of patentability.
II.
In Benson, the Supreme Court encountered the question of whether a method for converting binary-coded decimals, which was useful in programming digital computers, was a patentable “process” under section 101. 409 U.S. at 64, 93 S.Ct. at 254. The Court, by reading a limitation not found in the statute into the term “process,” determined the method of conversion did not satisfy section 101.
In Parker v. Flook, 437 U.S. 584, 98 S.Ct. 2522, 57 L.Ed.2d 451 (1978), the Court followed Benson. Flook claimed a method for updating alarm limits during catalytic conversion of hydrocarbons. The Court found Flook’s method involving mathematical calculations — though applied to a post-solution use — unpatentable. Flook, 437 U.S. at 590, 98 S.Ct. at 2525. Flook clearly limited the Benson rule to mathematical formulae and mathematical algorithms. Id. 437 U.S. at 585, 587, 589, 590, 591, 592, 594, 595, 98 S.Ct. at 2523, 2524, 2525, 2525, 2526, 2526, 2527, 2528. By mixing the terms “formula” and “algorithm,” 437 U.S. at 585-86, 98 S.Ct. at 2523, however, Flook further confused the meaning of “mathematical algorithm.” As used by Benson, that term meant “a procedure for solving a given type of mathematical problem.” 409 U.S. at 65, 93 S.Ct. at 254. Thus, an “algorithm” required both a mathematical problem and a solution procedure. A “formula” does not present or solve a mathematical problem, but merely expresses a relationship in mathematical terms. A “formula,” even under Benson’s definition, is not an algorithm.
In the wake of Benson, the Court of Customs and Patent Appeals struggled to implement the algorithm rule.1 Much of the difficulty sprang from the obscurity of the terms invoked to preclude patentability — terms like “law of nature,” “natural phenomena,” “formulae,” or “algorithm.”2 *1063Benson, 409 U.S. at 65, 67, 93 S.Ct. at 254, 255; Flook, 437 U.S. at 593, 98 S.Ct. at 2527. In the context of a product’s subject matter patentability, Justice Frankfurter discussed this analytical difficulty:
It only confuses the issue, however, to introduce such terms as “the work of nature” and the “laws of nature.” For these are vague and malleable terms infected with too much ambiguity and equivocation. Everything that happens may be deemed “the work of nature,” and any patentable composite exemplifies in its properties “the laws of nature.” Arguments drawn from such terms for ascertaining patentability could fairly be employed to challenge almost every patent.
Funk Bros. Seed Co. v. Kalo Inoculant Co., 333 U.S. 127, 134-35, 68 S.Ct. 440, 443, 92 L.Ed. 588 (1948) (Frankfurter, J., concurring). When attempting to enforce a legal standard embodied in broad, vague, nonstatutory terms, the courts have floundered.
At length, in 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 (CCPA 1980), the Court of Customs and Patent Appeals settled on a two-step test to detect unpatentable algorithms under the Benson rule:
First, the claim is analyzed to determine whether a mathematical algorithm is directly or indirectly recited. Next, if a mathematical algorithm is found, the claim as a whole is further analyzed to determine whether the algorithm is “applied in any manner to physical elements or process steps,” and, if it is, it “passes muster under § 101.”
In re Pardo, 684 F.2d 912, 915, 214 USPQ 673, 675-76 (CCPA 1982) (citing In re Abele, 684 F.2d 902, 214 USPQ 682 (CCPA 1982)). Walter adopted Flook’s implicit limitation of the Benson rule to “mathematical algorithms.” 618 F.2d at 764-65 n. 4. Like Flook, however, Walter confused “mathematical algorithms” with calculations, formulas, and mathematical procedures generally. Id.
Although downstream from Benson, this Freeman-Waiter fork hid some of the same unnavigable cross-currents. In the first place, the term “mathematical algorithm” remained vague. Without a statutory anchor, this term was buffeted by every judicial wind until its course was indiscernible. The obscurity of the term “mathematical algorithm” is evident in two cases. In Pardo, 684 F.2d 912, the court narrowly limited “mathematical algorithm” to the execution of formulas with given data. In the same year, the court in In re Meyer, 688 F.2d 789, 215 USPQ 193 (CCPA 1982), sweepingly interpreted the same term to include any mental process that can be represented by a mathematical algorithm.
The second part of the test had similar uncertainties. The test did not suggest how many physical steps a claim must take to escape the fatal “mathematical algorithm” category. In Abele, 684 F.2d 902, the court upheld claims applying “a mathematical formula within the context of a process which encompasses significantly more than the algorithm alone.” Id. at 909. Thus, the court apparently made compliance with the two-part test a function of the “significance” of additions to the algorithm — hardly a predictable standard.
The Court of Customs and Patent Appeals later clarified that the two-part algorithm is not the exclusive test for detecting unpatentable subject matter. Meyer, 688 F.2d at 796. Indeed, the court abandoned the two-step test in In re Taner, 681 F.2d 787, 214 USPQ 678 (CCPA 1982).
With the advent of the Court of Appeals for the Federal Circuit, this court continued to grapple with the inherent vagueness of the two-part test for unpatentable algorithms. See In re Grams, 888 F.2d 835, 12 USPQ2d 1824 (Fed.Cir.1989); In re Iwahashi, 888 F.2d 1370, 12 USPQ2d 1980 (Fed.Cir.1989). At one point, this court clarified *1064that failure to satisfy the second prong of the two-part test “does not necessarily doom the claim.” Grams, 888 F.2d at 839. Instead this court recommended asking the .broader question of “What did applicants invent?” in the context of the claim and its supporting disclosure. Id. At another point in the same opinion, this court put the central question in terms of whether “the claim in essence covers only the algorithm.” Id at 837.
Recognizing the obscurity of “algorithm,” this court in Iwahashi attempted to “take the mystery out of the term”:
[W]e point out once again that every step-by-step process, be it electronic or chemical or mechanical, involves an algorithm in the broad sense of the term. Since § 101 expressly includes processes as a category of inventions which may be patented and § 100(b) further defines the word “process” as meaning “process, art or method, and includes a new use of a known process, machine, manufacture, composition of matter, or material,” it follows that it is no ground for holding a claim is directed to nonstatutory subject matter to say it includes or is directed to an algorithm. This is why the proscription against patenting has been limited to mathematical algorithms....
888 F.2d at 1374 (emphasis in original). Because the Iwahashi claims as a whole described a machine or a manufacture (which fit within section 101 without regard to the meaning of “process”), this court in Iwahashi did not have occasion to resolve conflicts over the legal bounds of “mathematical algorithm.”
In sum, the two-part test was cast in the crucible of confusion created by Benson. If the Benson algorithm rule was the last and binding word on the meaning of “process” under section 101, this court would be obligated to follow — regardless of any imprecision or ambiguity. The Supreme Court, however, has already shown another reading of the Patent Act.
III.
In Diehr, the Supreme Court adopted a very useful algorithm for determining patentable subject matter, namely, following the Patent Act itself. Diehr upheld claims to a process for curing synthetic rubber which included use of a mathematical computer process. After setting forth the procedural history of the case, the Supreme Court stated:
In cases of statutory construction, we begin with the language of the statute.
Diehr, 450 U.S. at 182, 101 S.Ct. at 1054. Perhaps with an eye to the attempts to apply the Benson rule, the Court then noted:
[I]n dealing with the patent laws, we have more than once cautioned that “courts ‘should not read into the patent laws limitations and conditions which the legislature has not expressed.’ ”
Id. (citations omitted). Indeed Congress has never stated that section 101’s term “process” excludes certain types of algorithms. Therefore, as Diehr commands, this court should refrain from employing judicially-created tests to limit section 101.
With that introduction, the Court proceeded to interpret the word “process” from section 101. In doing so, the Court briefly examined the history of patent laws back to 1793. See also Chakrabarty, 447 U.S. at 308-09, 100 S.Ct. at 2207. The Court summed up the legislative intent of the patent laws with this broad admonition:
[T]he Committee Reports accompanying the 1952 Act... inform us that Congress intended statutory subject matter to “include anything under the sun that is made by man.” S.Rep. No. 1979, 82d Cong., 2d Sess., 5 (1952); H.R.Rep. No. 1923, 82d Cong., 2d Sess., 6 (1952).
Diehr, 450 U.S. at 182, 101 S.Ct. at 1054. This passage underscores the fallacy of creating artificial limits for the words of the 1952 Act.
Courts should give “process” its literal and predictable meaning, without conjecturing about the policy implications of that literal reading. Cf. Chakrabarty, 447 U.S. at 316-18, 100 S.Ct. at 2211-12. If Congress wishes to remove some processes from patent protection, it can enact such an exclusion. Again, in the absence of legis*1065lated limits on the meaning of the Act, courts should not presume to construct limits. The Supreme Court directed this court to follow the Act.
With that preface, the Supreme Court in Diehr specifically limited Benson. In the first place, the Court acknowledged the narrow definition of “mathematical algorithm” set forth by Benson. 450 U.S. at 186 n. 9, 101 S.Ct. at 1056 n. 9. Moreover, the Court expressly stated:
Our previous decisions regarding the pat-entability of “algorithms” are necessarily limited to the more narrow definition employed by the Court....
Id. Thus, after Diehr, only a mathematical procedure for solution of a specified mathematical problem is suspect subject matter.
The Supreme Court in Diehr also limited Benson to a further narrow proposition. That narrow proposition supports reliance on the statutory language of the 1952 Act, rather than a nonstatutory algorithm rule.
Citing Benson, the Court in Diehr stated:
This Court has undoubtedly recognized limits to § 101 and every discovery is not embraced within the statutory terms. Excluded from such patent protection are laws of nature, natural phenomena, and abstract ideas.
Our recent holdings in Gottschalk v. Benson, supra, and Parker v. Flook, supra, both of which are computer-related, stand for no more than these long-established principles.
450 U.S. at 185, 101 S.Ct. at 1056. In Taner, 681 F.2d at 791, this court’s predecessor said:
[I]n Diehr, the Supreme Court made clear that Benson stands for no more than the long-established principle that laws of nature, natural phenomena, and abstract ideas are excluded from patent protection and that “a claim drawn to subject matter otherwise statutory does not become nonstatutory because it uses a mathematical formula, computer program, or digital computer.” [Citations omitted.]
Thus, Diehr limited Benson and its progeny to three classes of unpatentable subject matter — laws of nature, natural phenomena, and abstract ideas. Indeed, in Chak-rabarty, the Court also cited Benson for the proposition that these three categories are unpatentable. 447 U.S. at 309, 100 S.Ct. at 2207; see also Flook, 437 U.S. at 593, 98 S.Ct. at 2527.
Because the Supreme Court cited Benson in Diehr, 450 U.S. at 185-86, 101 S.Ct. at 1056, this court has doubted whether Diehr limited the algorithm rule. Grams, 888 F.2d at 838. However, In re Taner, clearly interprets Diehr as strictly limiting Benson. 681 F.2d at 789, 791. More importantly, the Supreme Court instructed this court to apply the language of the 1952 Act without reading unexpressed limitations into the statute. Diehr, 450 U.S. at 182, 101 S.Ct. at 1054. Finally, to the extent that the Benson rule applies to mathematical algorithms in the wake of Diehr, the Supreme Court defined “mathematical algorithm” very narrowly.
By strictly limiting Benson, the Supreme Court signalled a change in the focus for patentability from the algorithm rule to the statutory standards of the Patent Act. The Supreme Court confined Benson to a narrow proposition which certainly does not preclude patentability of the ’459 patent’s heart attack risk detection process.
The ’459 Patent
The ’459 patent discloses an apparatus and a method for analyzing electrocardiograph signals to detect heart attack risks. The apparatus is a machine and is covered by the Iwahashi rule. The method converts an analog signal to a digital signal which passes, in reverse time order, through the mathematical equivalent of a filter. The filtered signal’s amplitude is then measured and compared with a predetermined value.
The ’459 invention manipulates electrocardiogram readings to render a useful result. While many steps in the ’459 process involve the mathematical manipulation of data, the claims do not describe a law of nature or a natural phenomenon. Furthermore, the claims do not disclose mere ab*1066stract ideas, but a practical and potentially life-saving process. Regardless of whether performed by a computer, these steps comprise a “process” within the meaning of section 101.
The district court granted summary judgment in favor of Corazonix because “the claims of the ’459 patent are drawn to a nonstatutory mathematical algorithm and, as such, are unpatentable pursuant to the provisions of 35 U.S.C. § 101.” This erroneous conclusion illustrates the confusion caused by Benson and its progeny.
This conclusion is erroneous for several reasons. First, even if mathematical algorithms are barred from patentability,3 the ’459 patent as a whole does not present a mathematical algorithm. The ’459 patent is a method for detecting the risk of a heart attack, not the presentation and proposed solution of a mathematical problem. In Diehr, the Supreme Court viewed the claims as “an industrial process for molding of rubber products,” not a mathematical algorithm. 450 U.S. at 192-93, 101 S.Ct. at 1060. The ’459 patent’s claims as a whole disclose a patentable process.
Second, the '459 patent does not claim a natural law, abstract idea, or natural phenomenon. Diehr limited the Benson rule to these three categories, none of which encompass the ’459 patent.
Finally, and most important, Diehr refocused the patentability inquiry on the terms of the Patent Act rather than on non-statutory, vague classifications. Under the terms of the Act, a “process” deserves patent protection if it satisfies the Act’s requirements. The ’459 patent claims a “process” within the broad meaning of section 101. Therefore, this court must reverse and remand.
CONCLUSION
When determining whether claims disclosing computer art or any other art describe patentable subject matter, this court must follow the terms of the statute. The Supreme Court has focused this court’s inquiry on the statute, not on special rules for computer art or mathematical art or any other art.
The claims of the '459 patent define an apparatus and a process. Both are patentable subject matter within the language of section 101. To me, the Supreme Court’s most recent message is clear: when all else fails (and the algorithm rule clearly has), consult the statute. On this basis, I, too, would reverse and remand.

. See, e.g., In re Christensen, 478 F.2d 1392, 1396, 178 USPQ 35 (CCPA 1973) (Rich, J., concurring) ("The Supreme Court in Benson appears to have held that claims drafted in such terms are not patentable — for what reason remaining a mystery.”), overruled in part by In re Taner, 681 F.2d 787, 214 USPQ 678 (1982); In re Johnston, 502 F.2d 765, 773, 183 USPQ 172, 179 (CCPA 1974) (Rich, J., dissenting) ("I am probably as much — if not more — confused by the wording of the Benson opinion as many others.”); rev'd, Dann v. Johnston, 425 U.S. 219, 96 S.Ct. 1393, 47 L.Ed.2d 692 (1976); In re Chatfield, 545 F.2d 152, 157, 191 USPQ 730, 735 (CCPA 1976) (Nonstatutory claims are “drawn to mathematical problem-solving algorithms or to purely mental steps.”), cert. denied, Dann v. Noll, 434 U.S. 875, 98 S.Ct. 226, 54 L.Ed.2d 155 (1977).

. The Court in Diamond v. Diehr, 450 U.S. 175, 101 S.Ct. 1048, 67 L.Ed.2d 155 (1981), expressly recognized that the term algorithm "is subject to a variety of definitions.” 450 U.S. at 186 n. 9, 101 S.Ct. at 1056 n. 9. Even Benson's definition for "algorithm” creates legal problems. For instance, the Benson-Tabbot algorithm worked with numbers, but "solved” a "mathematical problem” only in a very loose sense. Rather the Benson-Tabbot algorithm translated symbols from one numerical system to another. Cf. In re Toma, 575 F.2d 872, 197 USPQ 852 (CCPA 1978) (Using a digital computer to translate technical languages was not an algorithm.); In re Freeman, 573 F.2d 1237, 197 USPQ 464 (CCPA 1978) (Using computer to transcribe alphanumeric characters was not an algorithm.).
Moreover some problems, even if expressed in mathematical terms, are not mathematical problems. Mathematics, like a language, is a form of expression. The operation of a machine, the generation of electricity, the reaction of two chemicals, a baseball batter’s swing, a satellite’s orbit — all are within the descriptive power of mathematics. The Court of Customs and Patent Appeals recognized this axiomatic point:
However, some mathematical algorithms ... represent ideas or mental processes and are simply logical vehicles for communicating possible solutions to complex problems.
In re Meyer, 688 F.2d 789, 794, 215 USPQ 193, 197 (CCPA 1982). No wonder the Benson rule is confusing when electrical, chemical, or mechanical processes escape scrutiny when expressed *1063ra written language, but become suspect when expressed in the mathematical language. In In re Grams, 888 F.2d 835, 12 USPQ2d 1824 (Fed. Cir.1989), for instance, a medical diagnostic process was considered an unpatentable “mathematical algorithm” even though it did not present, or propose a solution to, a mathematical problem at all.

. The Court in Diehr stated: "we concluded that such an algorithm, or mathematical formula, is like a law of nature, which cannot be the subject of a patent.” 450 U.S. at 186, 101 S.Ct. at 1056 (emphasis added). In fact, a mathematical algorithm does not appear in nature at all, but only in human numerical processes.
A law of nature is indeed not patentable, but for reasons unrelated to the meaning of "process." A law of nature, even if a process, is not "new” within the meaning of § 101. Moreover, in Sarker, this court’s predecessor gave another reason a law of nature cannot satisfy section 101. In re Sarker, 588 F.2d 1330, 1333, 200 USPQ 132, 137 (CCPA 1978). In sum, the Patent Act excludes laws of nature from patent protection even without a strained explanation excluding laws of nature from the meaning of "process." It is difficult to determine how or why mathematical algorithms are "like" laws of nature.