I. Introduction

One of the requirements for patentability under United States law is subject matter eligibility, as prescribed by 35 U.S.C. § 101. Under Section 101, an invention is eligible for a patent if it is a "new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof." Accordingly, an invention must fall within one of the four statutory categories of a process, machine, manufacture, or composition of matter. Section 101 has also been interpreted by courts to exclude certain categories of inventions, such as laws of nature, physical phenomena, and abstract ideas, i.e., the so-called exceptions. See Bilski v. Kappos, 130 S. Ct. 3218, 3227–28 (2010).

While it is important to look to recent cases for further clarification on subject matter eligibility, practitioners would be remiss to ignore an entire body of precedent by the United States Court of Customs and Patent Appeals ("CCPA") that may provide additional guidance on this requirement for patentability. What follows is a discussion of key cases heard by the CCPA1 and what they can teach us about subject matter eligibility, especially as it relates to subject matter most recently at the forefront of § 101 issues: software.

II. The Importance of Characterizing the Claimed Subject Matter

In one of the CCPA's earliest cases dealing with software, the patent at the center of the dispute was directed to the quantitative spectrographic analysis of a qualitatively-known mixture to determine unknown component concentrations with minimum error. In re Prater, 415 F.2d 1393, 1395 (CCPA 1969). The Examiner initially rejected the claims under § 101 based on In re Abrams, 188 F.2d 165 (CCPA 1951), which established that purely mental acts relied on for patentable novelty of the claim are not eligible for patent protection. Id. at 1398. However, the Court found that Abrams did not apply because the claims included a properly programmed general-purpose computer for carrying out the claimed process without human intervention. Id. at 1400-01. Thus, the claims in Prater were found to be eligible for patent protection under § 101 when they were characterized as a machine-implemented process, rather than a software process.

III. The CCPA Pulls Back from Abrams

That same year, the CCPA decided another case involving the patentability of a software-based invention: In re Bernhart, 417 F.2d 1395, 1396 (CCPA 1969). In Benhart, the patent was directed to a method and apparatus for automatically making a two-dimensional portrayal of a three-dimensional object from any desired angle and distance and on any desired plane of projection. Id. The Examiner rejected the claims under Abrams, based on the use of a prior art computer and plotting machine, wherein the novelty arose from the equations with which the computer was programmed, which are mental steps. Id. However, the Court disagreed with the principle that "[i]f, in an invention defined by a claim, the novelty is indicated by an expression which does not itself fit in a statutory class (in this case not a machine or a part thereof), then the whole invention is non-statutory since all else in the claim is old." Id. at 1399.

In rejecting this principle, the Court noted that denying patents on machines merely because their novelty may be explained in terms of laws of physics would be incompatible with Congress's mandate in § 101 that a machine is patent eligible. Id. The Court also relied on the language of § 101 that a "new and useful improvement" is patent eligible to reason that a machine is improved when programmed with new and unobvious software, and is accordingly eligible for patent protection. Id. at 1400. From there, the Court explained that the invention at hand was not directed to mental steps, but rather required a digital computer, as well as a planar plotting apparatus to carry out the claimed steps. Id. at 1401. The Court then expressed concern with finding that the claimed process could be done mentally, as such a holding would essentially amount to holding "that a human mind is a digital computer or its equivalent, and that a draftsman is a planar plotting apparatus or its equivalent." Id. Under this reasoning, the Court found the claims to be patent-eligible. Id. Thus, the CCPA's reasoning in Bernhart may be useful in arguing that a claim directed to novel and unobvious software implemented on a computer is not directed to mental steps because the computer itself falls within a statutory category eligible for patent protection.

IV. The "Technological Arts" Doctrine

The following year, the CCPA considered the subject matter eligibility of a patent directed to "obtain[ing] seismograms which delineate with a high degree of precision the nature of the subsurface formations in the earth's crust." In re Musgrave, 431 F.2d 882 (CCPA 1970). The Examiner rejected the claims under § 101 because the patentability of the claims was dependent on the mental steps set forth in the claims. Id. at 1358. The Court disagreed with the Examiner that the claims recited purely mental steps. Id. at 1365. First, the Court defined a mental step to include:

[a]ny method or step in a method which can be manually performed and requires the use of the human eyes for detection or determination of any condition, such as temperature, pressure, time, etc., and/or the use of the hands for the purpose of manipulating, such as turning off or on or regulating a given device in a certain manner or at a certain time, etc., to produce a certain result. Id.

From there, the Court explained that such steps are not "purely" mental steps, which are prohibited from being patented. Id. The Court also noted the lack of a single "decision that holds that a method is per se unpatentable merely because its practice requires that the operator thereof must think." Id. Rather, the Court explained, the only requirement for a process to fall within the statutory bounds of § 101 "is that it be in the technological arts." Id. at 1367. Thus, the Court expanded a § 101 process to include any "sequence of operational steps" that can be performed by a machine "to promote the progress of useful arts." Id.

V. Recent Developments and The Modern Test

The Supreme Court issued several opinions regarding subject matter eligibility that limited the patentability of software. See, e.g., Gottschalk v. Benson, 409 U.S. 63 (1972) (holding that an algorithm for converting binary-coded decimal (BCD) numerals into pure binary numerals is unpatentable because the patent "would wholly pre-empt the mathematical formula and in practical effect would be a patent on the algorithm itself"); Parker v. Flook, 437 U.S. 584, 198 USPQ 193 (1978) (explaining that "the novelty of the mathematical algorithm is not a determining factor at all"); Diamond v. Diehr, 450 U.S. 175, 209 USPQ 1 (1981) (describing that "[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").

After the CCPA was abolished, the Supreme Court established the modern test for subject matter eligibility under § 101 in Alice Corp. Pty. Ltd. v. CLS Bank Intern., 573 U.S. 208 (2017). The first step is to "determine whether the claims at issue are directed to a patent-ineligible concept." Id. at 218. If a claim is found to be directed to such a concept—e.g., laws of nature, physical phenomena, and abstract ideas—at the first step, it must then be examined "to determine whether it contains inventive concept sufficient to transform the claimed abstract idea into a patent-eligible application." Id. at 221 (citing Mayo Collaborative Services v. Prometheus Laboratories, Inc., 132 S. Ct. 1289, 1297 (2012)) (internal quotations omitted). Under Alice, "the mere recitation of a generic computer cannot transform a patent-ineligible abstract idea into a patent-eligible invention." Id. at 223.

Thus, unlike Prater, Bernhart, and Musgrave, the modern test does not necessarily justify the patentability of a generic computer implementing novel and unobvious software. It is beyond the scope of this article to analyze whether Alice in fact sub silentio overruled Prater, Bernhart, and Musgrave. As long as Alice did not in fact expressly overrule Prater, Bernhart, and Musgrave, a patent applicant might be able to distinguish the facts of the case at hand and contend that the claims at issue are closer factually to those in the CCPA en banc cases of Prater, Bernhart, and Musgrave

VI. Conclusion

Although the CCPA was abolished prior to the development of computer technology to the state in which we know it today, that Court highlighted several important concepts associated with subject matter eligibility under § 101. Prater contemplated the re-framing of the subject matter claimed to avoid patent eligibility issues under the "mental steps" doctrine of Abrams. Bernhart considered the legislative intent behind § 101 in denying a principle that would discard as patent ineligible an entire claim that contained mental steps. Musgrave based its "technological arts" doctrine on the fact that even "mental" steps include elements that are not purely mental, such as the use of the eyes and the hands. While the Alice test dominates determining subject matter eligibility today, the reasoning in each of Prater, Bernhart, and Musgrave still provides practitioners with meaningful bases to argue that a claim is eligible for patent protection, as long as the exact facts of Alice are not present.

Footnote

1. The vast majority of CCPA decisions have not been overruled by the CCPA or overturned by an en banc Court of Appeals for the Federal Circuit ("CAFC") and thus remain binding precedent. See South Corp. v. U.S., 690 F.2d 1368, 1369 (Fed. Cir. 1982).

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.