Skip to main content

Bringing Mayo into Focus: why patent law should treat laws of nature as human constructs that shape how we see the world, and not pre-existing relationships in nature

March 18, 2015

By Ian McMillan and Cameron Gale

In three recent patent cases1, the Supreme Court of the United States (“Supreme Court”) invalidated patents for claiming “abstract ideas” or “laws of nature”, but provided little clarity on the meaning of “abstract idea” or “law of nature”, and why or when a claim directed to this kind of subject matter will be invalid. The resulting uncertainty of when patent protection is available may discourage investment in some of the most innovative sectors of the economy, such as software related innovation and biotechnology, as it is precisely these areas in which such issues often arise.2

In part 1 of this paper, we review the basis for these judicially developed exceptions to patent protection, including briefly reviewing Bilski, Alice, and Mayo. In part 2 we consider some of the judicial exceptions in greater depth to reveal the ambiguity in “law of nature”, and argue that “law of nature” should be read in the sense of a scientific principle defined by humans, and not in the sense that a law of nature "reveals a relationship that has always existed.”3 With this suggestion in mind, in part 3 we review other exceptions to patentable subject matter, namely the printed matter and mental steps doctrines. Once laws of nature are understood as principles of science, we argue that the “law of nature” exception to patent protection significantly overlaps the printed matter and mental steps doctrines. While there remains considerable uncertainty about the scope of the judicial exceptions to patent protection, the printed matter and mental steps doctrines suggest that there may be another way of looking at the judicial exceptions that offers some hope for eventual clarity.  Part 4 concludes.

Part 1 – Background on Patentable Subject Matter and Recent Case Law

Article 1, section 8 of the US Constitution gives Congress the power “to promote the progress of science and useful arts, by securing for limited times to authors and inventors the exclusive right to their respective writings and discoveries.”4 35 U.S.C. §101 defines patentable inventions as “any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof”.5 The definition of patentable inventions in s.101 is a “dynamic provision designed to encompass new and unforeseen inventions.”6 Over time, a number of implicit exceptions to s.101 have been developed by the Supreme Court to exclude “laws of nature, natural phenomena, and abstract ideas” from patent eligibility.7

These exceptions mean that a new and useful process, machine, manufacture, or composition of matter can still be excluded from patent eligibility if it is considered a “law of nature”, a “natural phenomena”, or an “abstract idea”. To determine if an invention is eligible for patenting, we must understand what the terms “law of nature” and “abstract idea” mean. But so far the Supreme Court has failed to provide any clear definition of these terms that could clarify their scope. The Supreme Court has also recognized that an application of a judicial exception “to a known structure or process may well be deserving of patent protection.”8 However, the distinction between claims to a judicial exception and claims to a patent eligible application of a judicial exception also remains elusive.

The cases discussed below illustrate the lack of clarity of the judicial exceptions for “abstract ideas” and “laws of nature”. Furthermore, these cases help illustrate why the justification for these exceptions is unclear, particularly justifications of the exception for “laws of nature”. The lack of justification contributes to the lack of clarity as if the reasons for the judicial exceptions were known, the extent to which those reasons apply in any particular case could be used to form an opinion on whether patent protection is available or not.

Mayo Collaborative Services v. Prometheus Laboratories Inc.9

In Mayo, the Supreme Court rejected claims directed to a method of optimizing therapeutic efficiency for treating an immune-mediate gastrointestinal disorder. The claims were rejected for being directed to a “law of nature”.10 The claims involved administering an immunosuppressant to a subject, determining an associated metabolite level in the subject, and included a wherein clause where a first metabolite level indicated a need to increase the amount of the drug administered, while a second level indicated the need to decrease the amount of the drug administered.11

The Supreme Court determined that the patent asserted by Prometheus disclosed a natural law that reflected the “relationships between concentrations of certain metabolites in the blood and the likelihood that a dosage of a thiopurine drug will prove ineffective or cause harm”.12This natural law was essentially recited in the wherein clause of the claims. Apart from the “law of nature” itself, the Supreme Court held that the other elements in the claims (the administering and determining steps) were “well-understood, routine, conventional activity previously engaged in by researchers in the field.”13 As a result, the “law of nature” recited by the claim was not transformed into patent-eligible subject matter.

Bilski v. Kappos14

In Bilski, the Supreme Court rejected claims covering a procedure for instructing buyers and sellers on how to protect against the risk of price fluctuations in a discrete section of the economy.15 The majority reasoned that the claims were “attempts to patent abstract ideas”16, relying “narrowly” on the precedents set in Benson17, Flook18, and Diehr. The claims described the concept of hedging, “a fundamental economic practice long prevalent in our system of commerce”, and allowing the patent would “pre-empt use of this approach in all fields.”19

CLS Bank International v. Alice Corporation20

In Alice, the court rejected claims21 “drawn to the abstract idea of intermediated settlement”.22 The Court compared the claims to those in Bilski to determine that “intermediated settlement, like hedging, is an abstract idea beyond the scope of §101.”23 In contrast to Bilski¸ the claims at issue in Alice explicitly recited physical components such as a data storage unit and a computer. Nonetheless, the Court rejected the claims on the basis that “merely requiring generic computer implementation” does not transform an “abstract idea” into patentable subject matter.24

Part 2 – Ambiguities in the Exceptions for “Abstract Ideas” and “Laws of Nature”

“Abstract Ideas”

The Bilski and Alice decisions, unfortunately, do not provide much guidance about how to determine whether claims are directed to an “abstract idea”.25 In the concurring opinion in Bilski, Justice Stevens highlights that the court “never provides a satisfying account of what constitutes an unpatentable abstract idea.”26 Justice Stevens further suggests that the majority’s approach could be interpreted to mean “that any process that utilizes an abstract idea is itself an unpatentable, abstract idea”, but that this approach would “undermine a host of patentable processes”.27

In Alice, the Supreme Court explicitly refused to define “abstract ideas”, and analogized the claims in Alice to those in Bilski to hold that Alice’s claims were directed to “abstract ideas”.28 Thus, we have yet to get a satisfying account of what the Supreme Court means by “abstract ideas”, and how this term might affect processes one might otherwise normally considered patentable.29 At most, we may assume that computer implementations of business methods such as those at issue in Bilski and Alice are likely to be unpatentable. Nonetheless, the question remains as to what exactly distinguishes the methods in Alice or Bilski from other software related inventions that would seem to be patentable, especially since the Supreme Court has specifically rejected excluding business methods from patent eligibility.30 This lack of clarity may discourage innovators in software-related fields from pursuing patent protection and thereby disclosing their innovations to the public.

“Laws of Nature”

In Flook, the Supreme Court states that a law of nature “reveals a relationship that has always existed”.31 On this basis, the Federal Circuit has asserted that “laws of nature” cannot be patented because “a person cannot truly “invent” an abstract idea or scientific truth. He or she can discover it, but not invent it.”32 This justification is difficult to maintain when examining some “laws of nature” the Supreme Court considers exemplary. For instance, in Prometheus the relationship in question was between a human-created immunosuppressant and a metabolite produced by the body in response to the immunosuppressant. This particular relationship could not have existed before the immunosuppressant was created—the relationship is only the result of human intervention. Thus, this relationship appears more analogous to an invention than to a discovery—it does not reflect a relationship that has always existed.

The Supreme Court also appears to use the terms “law of nature”, “scientific truth”, and “scientific principle” interchangeably.33 This creates further ambiguity in the scope of the term “law of nature” because scientific principles are defined based on a particular frame of reference. These scientific frames of reference may change over time, and reasonable individuals may disagree about whether particular scientific principles are correct. For instance, the Supreme Court asserts in Mayo that Newton could not “have patented the law of gravity”.34 But as Chief Justice Rader pointed out in the Federal Circuit’s en banc decision in Alice “gravity is not a natural law in Einsteinian theory, but a symptom of a curved universe” (emphasis added).35 As Chief Justice Rader indicates, the existence of a “law of nature” often depends on the scientific frame of reference used.

A “law of nature” or “scientific principle” may be understood as a way of rationalizing human experience based on the particular frame of reference (or worldview) being applied. Consider that prior to the acceptance of heliocentrism (the astronomical model in which the planets revolve around the Sun) it was widely accepted that the Earth was the orbital centre of celestial bodies. As Justice Newman at the Federal Circuit in Alice states, scientific principles are “a creation of the human mind, with its freely invented ideas and concepts.”36 To put it another way, “scientific principles” might be considered an expression of human understanding (i.e. information) that can be held in the human mind or conveyed using forms of communication such as printing. While a “law of nature” may exist in the human mind (and in written form such as a textbook) it is difficult to determine whether a “law of nature” truly exists, and even more difficult to assess whether a “scientific principle” is a “law of nature”.

Thus, we might look to some judicial doctrines that have considered the patent eligibility of inventions involving the human mind and the conveyance of information. The mental steps and printed subject matter doctrines are two such doctrines. These doctrines might provide a framework for patent eligibility with improved clarity and without the inherent metaphysical baggage associated with “laws of nature”.


Part 3 – Alternative Approaches to Patentable Subject Matter: Mental Steps and Printed Matter

Mental Steps Doctrine

The mental steps doctrine was first described in In re Abrams37 (although it was not actually adopted by the court in that case).38 Generally, the mental steps doctrine excludes claims where all the steps are purely mental in character or where the alleged novelty in the claim resides solely in one or more mental steps.39 This doctrine tends to be justified on the basis that thought or mental processes alone are not patent eligible.40 Claims including mental steps may be permissible where the novelty resides in one or more positive and physical steps.

This form of the mental steps doctrine appears consistent with the rulings in both Mayo and Bilski. In both cases, the novel aspects of the rejected claims could read on processes performed by a human mind.41 While the mental steps doctrine has never been fully accepted by courts, it seems consistent with the rejection from patent eligibility of claims that cover “abstract ideas” and “laws of nature”, while considering claims for applications of “abstract ideas” and “laws of nature” patent eligible. The Federal Circuit has also interpreted the Supreme Court’s decision in Benson as holding that “mental processes—or processes of human thinking—standing alone are not patentable even if they have practical application.”42 This holding might allow courts to consider and apply the mental steps doctrine while still relying on Supreme Court precedent.

In Alice the Supreme Court extended the reach of the “abstract ideas” to exclude claims including physical computer components implementing an “abstract idea” from patent eligibility. These claims cannot read on processes performed by the human mind (without ignoring the actual claim limitations). Accordingly, the mental steps doctrine, as set out above, seems insufficient to prevent the claims at issue in Alice from being patent eligible.

Printed Matter Doctrine

The printed matter doctrine attempts to address the issue of whether a claim to a combination of information and a substrate is patent eligible when the difference between the claimed subject matter and the prior art is the content of the information.43 Traditionally, printed matter by itself did not fall within any statutory class of patentable subject matter.44 The printed matter doctrine arose out of cases that prohibited mental theories or abstractions from patent eligibility.45 Typically, this doctrine has been used to exclude from patent eligibility inventions where the novelty resides in the content of the information conveyed by the printed matter. An exception to this rule allows printed matter to be an element of a patent eligible claim if the claim concerns a new and useful relation between the printed matter and a physical structure.46

It is easy to see how this doctrine may provide insight into the patent eligibility of software-related inventions. In some sense, software can be considered information stored on a memory for instructing a computer to perform a particular function. Thus, this doctrine could be used to consider the patent eligibility of software claims that include physical elements and thus may not be precluded under the mental steps doctrine. The question then becomes, when does a combination of software with known computer components provide a new and useful relation? The printed matter doctrine suggests that we consider the differences between the claimed invention and the prior art, and determine whether the difference (i.e. novelty) provides some useful function to the already known components of the prior art.

Some uncertainty would still remain with this approach, for example when applying the mental steps and printed matter doctrines to cases such as Alice. Alice involved the configuration of known computer components to provide a system and method for performing intermediated settlement. The novelty in Alice might be considered the instructions (i.e. software) used to configure those components for performing the particular method, which seems analogous to printed matter. Applying the Supreme Court’s holding in Alice using the language of the printed matter doctrine, we would then conclude that the configuration of these components to perform a method of intermediated settlement does not provide a useful and functional relationship between the instructions and the computer components.

Point-Of-Novelty Analysis

Both the printed matter and mental steps doctrine consider the patentability of claims by examining the point-of-novelty of the claims.47 While the point-of-novelty approach seems to conflict with the Supreme Court’s stated approach to s.101, it may reflect the analysis the Supreme Court actually uses. For instance, in Mayo the Court determines that the invention of the patent is the relationship between the metabolite level and whether therapy is likely to be effective. Apart from this “natural law”, the other claim steps are deemed to be conventional and routine. How can steps be considered conventional and routine without looking to the prior art?48

While the Supreme Court does not equate conventional, routine, well-understood elements with elements being found in the prior art, it begs the questions of how one would determine what is conventional, routine and well-understood activity in the relevant field. It stands to reason that these activities would necessarily be found in the prior art. Thus the “inventive concept” that renders a claim directed to a judicial exception “significantly more” than a claim to the exception itself is likely to be found at the “point-of-novelty” of the claimed invention. The printed matter and mental steps doctrine at least make explicit that claims are examined at the point-of-novelty.49

Part 4 - Conclusion

In this paper, we have reviewed the Supreme Court’s exceptions to patent eligibility for “abstract ideas” and “laws of nature” and have argued that both terms are extremely unclear as "law of nature" is highly ambiguous while "abstract idea” is indefinite. An alternative approach to assessing patent eligibility that avoids these issues is desirable.

If a law of nature is thought of as a scientific principle, then it becomes a human construct that can be grasped by the mind to perform mental steps, or communicated to readers via printed matter. Also, a different justification for this exception arises, that the processes of human thinking must be free from patent protection. Admittedly, this justification needs a lot of development, but given that the Supreme Court has failed, in well over 100 years of jurisprudence, to provide a clear justification for the judicial exceptions, it may well be worth a try.


1 Mayo Collaborative Services v. Prometheus Laboratories Inc., 566 US __ (2012) [Mayo]; Bilski v. Kappos, 561 US __ (2010) [Bilski]; CLS Bank International v. Alice Corporation, 573 U. S. __ (2014) [Alice]. For the sake of brevity we are not considering Association for Molecular Pathology v. Myriad Genetics, Inc., 569 US __ (2013) [Myriad] in this paper.

2 See Alice infra note 1, Opinion of Justice Newman slip op at 3.

3 See Flook infra note 18 at 593: “The rule that the discovery of a law of nature cannot be patented rests, not on the notion that natural phenomena are not processes, but rather on the more fundamental understanding that they are not the kind of "discoveries" that the statute was enacted to protect.” See also footnote 15: “The underlying notion is that a scientific principle, such as that expressed in respondent's algorithm, reveals a relationship that has always existed.” Arguably, if a law of nature is considered “a relationship that has always existed”, then no biological relationship constitutes a law of nature as all biological relationships themselves evolved over time.

4 U.S. Const. art. I, § 8.

5 35 U.S.C. §101.

6 Bilski infra note  slip op. at 8.

7 See e.g. Mayo supra note 1 (slip op. at 1); Alice supra note 1 (slip op. at 5); Myriad supra note 1 (slip op. at 11);.

8 Diamond v. Diehr, 450 US 175 (1981) [Diehr] at 187. See also Mayo supra note 1 (slip op. at 2): “The Court has recognized, however, that too broad an interpretation of this exclusionary principle could eviscerate patent law. For all inventions at some level embody, use, reflect, rest upon, or apply laws of nature, natural phenomena, or abstract ideas.”

9 566 US __ (2012).

10 Ibid, slip op. at 7. The district court had identified the natural law or natural phenomena as “correlations between thiopurine metabolite levels and the toxicity and efficacy of thiopurine drug dosages.”

11 In Mayo, the Supreme Court considered claim 1 of US Patent No. 6,355,623 to be representative (see slip op. at 5):

1. A method of optimizing therapeutic efficacy for treatment of an immune-mediated gastrointestinal disorder, comprising:

(a) administering a drug providing 6-thioguanine to a subject having said immune-mediated gastrointestinal disorder; and

(b) determining the level of 6-thioguanine in said subject having said immune-mediated gastrointestinal disorder,

wherein the level of 6-thioguanine less than about 230 pmol per 8×108 red blood cells indicates a need to increase the amount of said drug subsequently administered to said subject and

wherein the level of 6-thioguanine greater than about 400 pmol per 8×108 red blood cells indicates a need to decrease the amount of said drug subsequently administered to said subject.

The claims at issue in Mayo are very broad. The district court construed the claims as not being limited to instances in which doctors altered dosage levels. Thus, beyond the administering and determining steps, no other acts were required for infringement.

12 Ibid slip op at 8.

13 Ibid, slip op. at 4.

14 561 US _ (2010).

15 Ibid.

16 Ibid, slip op at 13: “all members of the Court agree that the patent application at issue falls outside of §101 because it claims an abstract idea.”

17 Gottschalk v Benson, 409 U.S. 63 (1972) [Benson].

18 Parker v Flook, 437 U.S. 584 (1978) [Flook].

19 Bilski supra note 1, slip op. at 15.

20 573 U. S. ____ (2014).

21 The Federal Circuit considered claim 1 of Alice’s US Patent No. 7,149,720 to be representative of the contested system claims (see 685 F.3d 1341 (Fed. Cir. 2012), slip op at 32):

1. A data processing system to enable the exchange of an obligation between parties, the system comprising:

a data storage unit having stored therein information about a shadow credit record and shadow debit record for a party, independent from a credit record and debit record maintained by an exchange institution; and

a computer, coupled to said data storage unit, that is configured to

(a) receive a transaction;

(b) electronically adjust said shadow credit record and/or said shadow debit record in order to effect an exchange obligation arising from said transaction, allowing only those transactions that do not result in a value of said shadow debit record being less than a value of said shadow credit record; and

(c) generate an instruction to said exchange institution at the end of a period of time to adjust said credit record and/or said debit record in accordance with the adjustment of said shadow credit record and/or said shadow debit record, wherein said instruction being an irrevocable, time invariant obligation placed on said exchange institution.

22 Alice supra note 1, slip op at 1.

23 Ibid slip op at 9 (internal quotations omitted). See also slip op. at 10: “…there is no meaningful distinction between the concept of risk hedging in Bilski and the concept of intermediated settlement at issue here. Both are squarely within the realm of “abstract ideas” as we have used that term” (emphasis added). This may suggest that the Court recognizes that its use of “abstract ideas” is unclear.

24 Ibid, slip op at 1, 13.

25 See Justice Stevens concurring reasons in Bilski for a discussion of some of the problems in the majority’s rationale for excluding abstract ideas.

26 Stevens concurrence at 8-9.

27 Stevens concurrence at 8-9.

28 Alice supra note 1, slip op at 10: “In any event, we need not labor to delimit the precise contours of the “abstract ideas” category in this case. It is enough to recognize that there is no meaningful distinction between the concept of risk hedging in Bilski and the concept of intermediated settlement at issue here. Both are squarely within the realm of “abstract ideas” as we have used that term.”

29 For example, in the oral proceedings in Alice, counsel for CLS stated that a process for data compression would be patent eligible. Nonetheless, the analysis performed in Bilski and Alice could potentially be extended to exclude those types of claims from patent eligibility.

30 In the oral transcripts (at pages 31-32) counsel for CLS indicated that data compression methods should be patentable. See also footnote 40 in Justice Stevens’ concurring judgement in Bilski.

31 Flook supra note 18 at 593.

32 717 F.3d 1269 (Fed. Cir. 2013) slip op at 20.

33 See Flook supra note 18 at 593 and at footnote 15.

34 See also Flook supra note 18 at footnote 15.

35 See Additional Reflections of Chief Justice Rader in 717 F.3d 1269 (Fed. Cir. 2013).

36 717 F.3d 1269 (Fed. Cir. 2013) judgement of Justice Newman at 10-11, quoting Albert Einstein & Leopold Infeld, The Evolution of Physics 310 (1938).

37 188 F.2d 165 (C.C.P.A. 1951) [Abrams];

38 Ibid at 166-167.

39 As stated in Abrams at 166:

1. If all the steps of a method claim are purely mental in character, the subject matter thereof is not patentable within the meaning of the patent statutes.

2. If a method claim embodies both positive and physical steps as well as so-called mental steps, yet the alleged novelty or advance over the art resides in one or more of the so-called mental steps, then the claim is considered unpatentable for the same reason that it would be if all the steps were purely mental in character.

3. If a method claim embodies both positive and physical steps as well as so-called mental steps, yet the novelty or advance over the art resides in one or more of the positive and physical steps and the so-called mental step or steps are incidental parts of the process which are essential to define, qualify or limit its scope, then the claim is patentable and not subject to the objection contained in 1 and 2 above.

40 See Abrams: “Citation of authority in support of the principle that claims to mental concepts which constitute the very substance of an alleged invention are not patentable is unnecessary. It is self-evident that thought is not patentable.”; Comiskey: “mental processes—or processes of human thinking—standing alone are not patentable even if they have practical application…Following the lead of the Supreme Court, this court and our predecessor court have refused to find processes patentable when they merely claimed a mental process standing alone and untied to another category of statutory subject matter event when a practical application was claimed.”

41 Once a doctor is aware of the relationship between the metabolite levels and therapeutic effectiveness disclosed by the Prometheus application, the wherein clause is effectively a doctor reading the results of the determining step and applying the disclosed relationship in his or her mind.

42 See Comiskey: “The Supreme Court has stated that "[p]henomena of nature, though just discovered, mental processes, and abstract intellectual concepts are not patentable, as they are the basic tools of scientific and technological work." Benson, 409 U.S. at 67, 93 S.Ct. 253 (emphasis added)…. Following the lead of the Supreme Court, this court and our predecessor court have refused to find processes patentable when they merely claimed a mental process standing alone and untied to another category of statutory subject matter even when a practical application was claimed.”

43 See Chisum on Patents 1.02[4][a] at 1-26.

44 See e.g. in re Miller 418 F.2d 1392 (CCPA 1969).

45 See Chisum Supra note 43.

46 See e.g. Cincinnati Traction Co. v Pope 210 F. 443 (6th Circuit 1913).

47 However, these doctrines perform the analysis based on obviousness once the non-patentable subject matter is excluded.

48 Or applying hindsight bias.

49 This also does not conflict with the requirement to consider the claim as a whole, as the point-of-novelty can be a new use of old elements (see definition of process in s.100, for example), which may be shown in the claim by the “ordered combination” of elements.

Content shared on Bereskin & Parr’s website is for information purposes only. It should not be taken as legal or professional advice. To obtain such advice, please contact a Bereskin & Parr LLP professional. We will be pleased to help you.


Ian McMillan Ian McMillan
B.Sc. (Math & Eng.), LL.B., LL.M.
905.817.6103  email Ian McMillan
Cameron Gale Cameron Gale
B.Eng. (Elec. and Comp.), J.D.
416.957.1645  email Cameron Gale