Parker v. Flook
, was a 1978 United States Supreme Court decision that ruled that an invention that departs from the prior art only in its use of a mathematical algorithm is patent-eligible only if the implementation is novel and unobvious. The algorithm itself must be considered as if it were part of the prior art. The case was argued on April 25, 1978 and was decided June 22, 1978. This case is the second member of the Supreme Court's patent-eligibility trilogy.
The case revolves around a patent application for a "Method for Updating Alarm Limits
". These limits are numbers between which a catalytic converter
A catalytic converter is a device used to convert toxic exhaust emissions from an internal combustion engine into non-toxic substances. Inside a catalytic converter, a catalyst stimulates a chemical reaction in which noxious byproducts of combustion are converted to less toxic substances by dint...
is operating normally. The numbers are determined by taking a time-weighted average of values of a relevant operating parameter, such as temperature inside the reactor, in accordance with a smoothing algorithm. When the values of these numbers leave this range an alarm may be sounded. The claims, however, were directed to the numbers (the "alarm limits") themselves.
Flook's method was identical to previous systems except for the mathematical algorithm. In fact, although the patent examiner and the Supreme Court opinions assumed that Flook had originated the mathematical technique, someone else had published it a number of years earlier. In Gottschalk v. Benson
Gottschalk v. Benson, was a United States Supreme Court case in which the Court ruled that a process claim directed to a numerical algorithm, as such, was not patentable because "the patent would wholly pre-empt the mathematical formula and in practical effect would be a patent on the algorithm...
, the court had ruled that the discovery of a new formula is not patentable. This case differed from Benson
by including a specific application—catalytic conversion of hydrocarbons—for the formula as a claim limitation (a so-called field of use limitation). The patent examiner rejected the patent application as "in practical effect" a claim to the formula or its mathematics. When the decision was appealed, the Board of Appeals of the Patent and Trademark Office
The United States Patent and Trademark Office is an agency in the United States Department of Commerce that issues patents to inventors and businesses for their inventions, and trademark registration for product and intellectual property identification.The USPTO is based in Alexandria, Virginia,...
sustained the examiner's rejection.
Next, the Court of Customs and Patent Appeals (CCPA) reversed the Board's decision, saying that the patent only claimed the right to the equation in the limited context of the catalytic chemical conversion of hydrocarbons, so that the patent would not wholly pre-empt the use of the algorithm. Finally, the Government, on behalf of the (Acting) Commissioner of Patents and Trademarks, filed a petition for a writ of certiorari
Certiorari is a type of writ seeking judicial review, recognized in U.S., Roman, English, Philippine, and other law. Certiorari is the present passive infinitive of the Latin certiorare...
to the CCPA in the Supreme Court.
The Supreme Court's Decision
The law which is applicable to this case is section 101 of the Patent Act. If Flook's patent claim can meet the definition of a "process" under that law then it is patent-eligible (that is, it is the kind of thing that can receive a patent if it is also novel, unobvious, and the like). The Court decided that the patent claim under review was instead a claim to a "principle" or a "law of nature" and thus not patent-eligible. The Court relied on a line of cases following from the Neilson blast furnace case. The principle of that case, as explained in O’Reilly v. Morse
, is that that patent-eligibility must be analyzed on the basis of it being as if the principle, algorithm, or mathematical formula were already well known (was in the prior art
Prior art , in most systems of patent law, constitutes all information that has been made available to the public in any form before a given date that might be relevant to a patent's claims of originality...
). Flook's process is thus ineligible for a patent "because, once that algorithm is assumed to be within the prior art, the application, considered as a whole, contains no patentable invention." In a nutshell:
Even though a phenomenon of nature or mathematical formula may be well known, an inventive application of the principle may be patented. Conversely, the discovery of such a phenomenon cannot support a patent unless there is some other inventive concept in its application. [Emphasis supplied.]
The Court did not agree with Flook's assertion that the existence of a limitation to a specific field of use made the formula patent-eligible. The majority opinion said of this argument:
A competent draftsman could attach some form of post-solution activity to almost any mathematical formula; the Pythagorean theorem
In mathematics, the Pythagorean theorem or Pythagoras' theorem is a relation in Euclidean geometry among the three sides of a right triangle...
would not have been patentable, or partially patentable, because a patent application contained a final step indicating that the formula, when solved, could be usefully applied to existing surveying
See Also: Public Land Survey SystemSurveying or land surveying is the technique, profession, and science of accurately determining the terrestrial or three-dimensional position of points and the distances and angles between them...
The court moderated that assertion by agreeing that not all patent applications involving formulas are patent-ineligible by saying, "Yet it is equally clear that a process is not unpatentable simply because it contains a law of nature or a mathematical algorithm." Patents involving formulas, laws of nature, or abstract principles are eligible for patent protection if the implementation of the principle is novel and unobvious—unlike this case, in which it was conceded that the implementation was conventional. Accordingly, in Flook's case, there was no "other inventive concept in its application," and thus no eligibility for a patent.
Criticism and response to Flook
In In re Bergy
, a 1979 decision of the United States Court of Customs and Patent Appeals (CCPA), Judge Giles Rich extensively criticized Justice Stevens's Flook
opinion. The Supreme Court had vacated an earlier Bergy
opinion, with terse instructions that the CCPA should give the matter "further consideration in light of Parker v. Flook
, 437 U.S. 584 (1978)." Judge Rich began by protesting that "[t]he Court gave no intimation of what bearing it thought Flook
has on the single issue in these appeals [whether the claimed subject matter was patent-eligible], except as it may be gleaned from the Flook
opinion." After an exhaustive analysis of what Flook
, the Constitution, and the patent statute provide about the grant of patents--which said little or nothing about the patent-ineligibility of abstract ideas and how section 101 of the patent law relates to that--Judge Rich summarized his view: "To conclude on the light Flook
sheds on these cases, very simply, for the reasons we have stated, we find none."
Before reaching his conclusion, however, Judge Rich condemned the Flook
opinion as embodying:
an unfortunate and apparently unconscious, though clear, commingling of distinct statutory provisions which are conceptually unrelated, namely, those pertaining to the categories of inventions in § 101 which may be patentable and to the conditions for patentability demanded by the statute for inventions within the statutory categories, particularly the nonobviousness condition of § 103.
The reason for this confusion in the Court's opinion he attributed to "subversive nonsense" in the government's briefs for the Patent Office:
We have observed with regret that the briefs filed by the Solicitor General for Acting Commissioner Parker in Parker v. Flook, a case which, as the Court noted, "turns entirely on the proper construction of § 101," badly, and with a seeming sense of purpose, confuse the statutory-categories requirement of § 101 with a requirement for the existence of "invention." This they do by basing argument on the opening words of § 101, "Whoever invents or discovers," thereby importing into the discussion of compliance with § 101 a requirement for "invention" in a patentability sense.
To Judge Rich, even though section 101 says "whoever invents or discovers," there is no basis for importing into the analysis any inquiry into the nature of what it is that the patent applicants purports to have invented, and whether it is the kind of thing that can be patented as an invention. Thus, when the Flook
Court says that Flook's process is not the kind
of process that the patent law permits to be patented, even though it is a process in the ordinary dictionary sense of the word, Judge Rich finds the inquiry impermissible because "§ 101 was never intended to be a 'standard of patentability'; the standards, or conditions as the statute calls them, are in § 102 and § 103." The only legitimate question, he says, is whether the claimed subject matter is "new, useful, and unobvious."
Judge Rich could not agree that the implementation of a natural principle must be "inventive" rather than concededly conventional (as Flook had conceded). To him, that improperly mixed obviousness under section 103 up with statutory subject matter under section 101. But Judge Rich overlooked what Justice Stevens pointed out--that Flook did not purport
to have implemented the process in anything but a conventional way and did not purport to have added anything to what was previously known but the use of the smoothing formula. Justice Stevens saw the case as one in which Flook did not even purport to have invented anything capable of being patented. (Justice Stevens responded to the Bergy
critique in his dissenting opinion in the Diehr
Actually, the concession by Flook made the Flook
case an easy one. But one could hardly expect any applicant in a subsequent case to make a similar concession. It is unclear how to apply the principle of the Flook
case to other cases where no such concession exists. In one class of case, where the implementation is utterly trivial on its face, as in Funk v. Kalo Inoculant Co.
, the applicability of the same principle seems clear. But that appears to be the outer limit of the easy case. Once reasonable persons can differ on whether the implementation is barely at a remove from the natural principle, it would seem that the Flook
principle cannot be employed. If a full-scale Graham v. Deere
analysis must be used to evaluate the implementation, it would seem that the case can no longer be disposed of on section 101 grounds. That is what appears to have happened in the next member of the trilogy, Diamond v. Diehr