Diamond v. Diehr, Abridged

Majority opinion, section I.

The claimed invention is a process for molding raw, uncured synthetic rubber into cured precision products.

Respondents characterize their contribution to the art to reside in the process of constantly measuring the actual temperature inside the mold. According to the respondents, the continuous measuring of the temperature inside the mold cavity, the feeding of this information to a digital computer which constantly recalculates the cure time, and the signaling by the computer to open the press, are all new in the art.

Majority opinion, section II.

Analyzing respondents' claims according to the above statements from our cases, we think that a physical and chemical process for molding precision synthetic rubber products falls within the 101 categories of possibly patentable subject matter.

Majority opinion, section III.

Our conclusion regarding respondents' claims is not altered by the fact that in several steps of the process a mathematical equation and a programmed digital computer are used. 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, physical phenomena and abstract ideas.

Our recent holdings in Gottschalk v. Benson and Parker v. Flook, both of which are computer-related, stand for no more than these long established principles. In Benson, we held unpatentable claims for an algorithm used to convert binary code decimal numbers to equivalent pure binary numbers. We defined "algorithm" as a "procedure for solving a given type of mathematical problem," and we concluded that such an algorithm, or mathematical formula, is like a law of nature, which cannot be the subject of a patent.

Parker v. Flook presented a similar situation. The claims were drawn to a method for computing an "alarm limit." An "alarm limit" is simply a number and the Court concluded that the application sought to protect a formula for computing this number. Using this formula, the updated alarm limit could be calculated if several other variables were known. The application, however, did not purport to explain how these other variables were to be determined, nor did it purport "to contain any disclosure relating to the chemical processes at work, the monitoring of process variables, or the means of setting off an alarm system. All that is provided is a formula for computing an updated alarm limit."

In contrast, the respondents here do not seek to patent a mathematical formula. Instead, they seek patent protection for a process of curing synthetic rubber. Their process admittedly employs a well-known mathematical equation, but they do not seek to pre-empt the use of that equation. Rather, they seek only to foreclose from others the use of that equation in conjunction with all of the other steps in their claimed process.

Our earlier opinions lend support to our present conclusion that a claim drawn to subject matter otherwise statutory does not become nonstatutory simply because it uses a mathematical formula, computer program or digital computer.

It may later be determined that the respondents' process is not deserving of patent protection because it fails to satisfy the statutory conditions of novelty under 102 or nonobviousness under 103. A rejection on either of these grounds does not affect the determination that respondents' claims recited subject matter which was eligible for patent protection under 101.

Majority opinion, section IV.

A mathematical formula as such is not accorded the protection of our patent laws, and this principle cannot be circumvented by attempting to limit the use of the formula to a particular technological environment. Similarly, insignificant post-solution activity will not transform an unpatentable principle into a patentable process. To hold otherwise would allow a competent draftsman to evade the recognized limitations on the type of subject matter eligible for patent protection. On the other hand, when a claim containing a mathematical formula implements or applies that formula in a structure or process which, when considered as a whole, is performing a function which the patent laws were designed to protect (e.g., transforming or reducing an article to a different state or thing), then the claim satisfies the requirements of 101.

Dissent, section I.

Before discussing the major flaws in the Court's opinion, a word of history may be helpful.

Prior to 1968, well-established principles of patent law probably would have prevented the issuance of a valid patent on almost any conceivable computer program.

The Patent Office indicated, however, that a programmed computer could be a component of a patentable process if combined with unobvious elements to produce a physical result. The Patent Office formally adopted the guidelines in 1968.

The new guidelines were to have a short life. Beginning with two decisions in 1968, a dramatic change in the law as understood by the Court of Customs and Patent Appeals took place. By repudiating the well-settled "function of a machine" and "mental steps" doctrines, that court reinterpreted 101 of the Patent Code to enlarge drastically the categories of patentable subject matter. This reinterpretation would lead to the conclusion that computer programs were within the categories of inventions to which Congress intended to extend patent protection.

The "technological arts" standard was refined in In re Benson, in which the court held that computers, regardless of the uses to which they are put, are within the technological arts for purposes of 101.

In re Benson, of course, was reversed by this Court in Gottschalk v. Benson (1972). Justice Douglas' opinion for a unanimous Court made no reference to the lower court's rejection of the mental steps doctrine or to the new technological arts standard. Rather, the Court clearly held that new mathematical procedures that can be conducted in old computers, like mental processes and abstract intellectual concepts, are not patentable processes within the meaning of 101.

In Flook, this Court clarified Benson in three significant respects. First, Flook held that the Benson rule of unpatentable subject matter was not limited, as the lower court believed, to claims which wholly pre-empted an algorithm or amounted to a patent on the algorithm itself. Second, the Court made it clear that an improved method of calculation, even when employed as part of a physical process, is not patentable subject matter under 101. Finally, the Court explained the correct procedure for analyzing a patent claim employing a mathematical algorithm. Under this procedure, the algorithm is treated for 101 purposes as though it were a familiar part of the prior art; the claim is then examined to determine whether it discloses "some other inventive concept."

Although the Court of Customs and Patent Appeals in several post-Flook decisions held that program-related inventions were not patentable subject matter under 101, Flook was not enthusiastically received by that court. In subsequent cases, the court construedFlook as resting on nothing more than the way in which the patent claims had been drafted, and it expressly declined to use the method of claim analysis spelled out in that decision. The Court of Customs and Patent Appeals has taken the position that, if an application is drafted in a way that discloses an entire process as novel, it defines patentable subject matter even if the only novel element that the inventor claims to have discovered is a new computer program.

Dissent, section II.

In short, Diehr and Lutton do not claim to have discovered anything new about the process for curing synthetic rubber.

As the Court reads the claims in the Diehr and Lutton patent application, the inventors' discovery is a method of constantly measuring the actual temperature inside a rubber molding press. As I read the claims, their discovery is an improved method of calculating the time that the mold should remain closed during the curing process. If the Court's reading of the claims were correct, I would agree that they disclose patentable subject matter. On the other hand, if the Court accepted my reading, I feel confident that the case would be decided differently.

There are three reasons why I cannot accept the Court's conclusion that Diehr and Lutton claim to have discovered a new method of constantly measuring the temperature inside a mold. First, there is not a word in the patent application that suggests that there is anything unusual about the temperature-reading devices used in this process -- or indeed that any particular species of temperature-reading device should be used in it. Second, since devices for constantly measuring actual temperatures -- on a back porch, for example -- have been familiar articles for quite some time, I find it difficult to believe that a patent application filed in 1975 was premised on the notion that a "process of constantly measuring the actual temperature" had just been discovered. Finally, the Board of Patent Appeals expressly found that "the only difference between the conventional methods of operating a molding press and that claimed in [[the] application rests in those steps of the claims which relate to the calculation incident to the solution of the mathematical problem or formula used to control the mold heater and the automatic opening of the press. This finding was not disturbed by the Court of Customs and Patent Appeals and is clearly correct.

A fair reading of the entire patent application, as well as the specific claims, makes it perfectly clear that what Diehr and Lutton claim to have discovered is a method of using a digital computer to determine the amount of time that a rubber molding press should remain closed during the synthetic rubber curing process. There is no suggestion that there is anything novel in the instrumentation of the mold, in actuating a timer when the press is closed, or in automatically opening the press when the computed time expires. Nor does the application suggest that Diehr and Lutton have discovered anything about the temperatures in the mold or the amount of curing time that will produce the best cure. What they claim to have discovered, in essence, is a method of updating the original estimated curing time by repetitively recalculating that time pursuant to a well-known mathematical formula in response to variations in temperature within the mold. Their method of updating the curing time calculation is strikingly reminiscent of the method of updating alarm limits that Dale Flook sought to patent.

The essence of the claimed discovery in both cases was an algorithm that could be programmed on a digital computer.

Dissent, section III.

Proper analysis, therefore, must start with an understanding of what the inventor claims to have discovered -- or phrased somewhat differently -- what he considers his inventive concept to be. It seems clear to me that Diehr and Lutton claim to have developed a new method of programming a digital computer in order to calculate -- promptly and repeatedly -- the correct curing time in a familiar process.

If that method is regarded as an "algorithm" as that term was used in Gottschalk v. Benson, and in Parker v. Flook, and if no other inventive concept is disclosed in the patent application, the question must be answered in the negative. In both Benson and Flook, the parties apparently agreed that the inventor's discovery was properly regarded as an algorithm; the holding that an algorithm was a "law of nature" that could not be patented therefore determined that those discoveries were not patentable processes within the meaning of 101.

Even the Court does not suggest that the computer program developed by Diehr and Lutton is a patentable discovery. Accordingly, if we treat the program as though it were a familiar part of the prior art -- as well-established precedent requires -- it is absolutely clear that their application contains no claim of patentable invention. Their application was therefore properly rejected under 101 by the Patent Office and the Board of Patent Appeals.

Dissent, section IV.

The broad question whether computer programs should be given patent protection involves policy considerations that this Court is not authorized to address. Notwithstanding fervent argument that patent protection is essential for the growth of the software industry, commentators have noted that "this industry is growing by leaps and bounds without it." In addition, even some commentators who believe that legal protection for computer programs is desirable have expressed doubts that the present patent system can provide the needed protection.

Other criticism, however, identifies two concerns to which federal judges have a duty to respond. First, the cases considering the patentability of program-related inventions do not establish rules that enable a conscientious patent lawyer to determine with a fair degree of accuracy which, if any, programrelated inventions will be patentable. Second, the inclusion of the ambiguous concept of an "algorithm" within the "law of nature" category of unpatentable subject matter has given rise to the concern that almost any process might be so described and therefore held unpatentable.

In my judgment, today's decision will aggravate the first concern and will not adequately allay the second. I believe both concerns would be better addressed by (1) an unequivocal holding that no program related invention is a patentable process under 101 unless it makes a contribution to the art that is not dependent entirely on the utilization of a computer, and (2) an unequivocal explanation that the term "algorithm" as used in this case, as in Benson and Flook, is synonymous with the term "computer program." Because the invention claimed in the patent application at issue in this case makes no contribution to the art that is not entirely dependent upon the utilization of a computer in a familiar process, I would reverse the decision of the Court of Customs and Patent Appeals.