Finnegan attorneys Paul Browning, Christopher Johns, Sara Leiman and Yelena Morozova explain some of the differences between patent-eligibility standards in the U.S. and those in other parts of the world.

Ever year patentees file more patent applications in a wider range of countries. Since the Patent Cooperation Treaty (PCT) came into force in 1978, nearly four million PCT applications have been filed to enable patentees to obtain international protection for their inventions — and more than half of these PCT applications were filed in the last ten years.1A broad patent portfolio is of increasing importance to large and small companies in a variety of fields.

Yet, prosecuting patents in different countries can be challenging. Each country has its own laws for pursuing patent applications and achieving enforceable patents. And while treaties and other agreements (like the Paris Convention and the PCT) lay a foundation for many countries' patent systems, local patent law varies widely on the issue of patent eligibility.

Patent attorneys and the clients they serve therefore must be cognizant of these differences in eligibility law in different jurisdictions and take them into account when pursuing patent protection internationally.

In this article we focus on some of the more significant differences in subject matter eligibility in the United States and before the European Patent Office (EPO) and further briefly discuss the different approaches taken in other important jurisdictions around the world.

A. Eligibility Law in the United States

Patent eligibility in the United States is defined, in the first instance, by statute, which broadly permits the patenting of "any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof."

This broad scope has been limited, however, by courts, which have identified and, in some cases, broadly applied certain judicial exceptions to patent eligibility. Specifically, the U.S. Supreme Court identified "laws of nature, natural phenomena, and abstract ideas" as judicial exceptions to patent eligibility, holding that this subject matter may not be patented under U.S. law because they constitute the "basic tools of scientific and technological work."

The Supreme Court held that permitting patent rights that monopolize such basic tools may impede innovation rather than promote it, thus contradicting the purpose of patenting as dictated by the United States Constitution. Applying this principle, the Supreme Court has developed a two-part test (often called the "Mayo/Alice" test) to determine if patent claims are improperly directed to judicial exceptions and are thus ineligible for patenting.

In the first step of the Mayo/Alice test, the claims at issue are examined to determine if they are directed to any of the judicial exceptions, namely, laws of nature, natural phenomena or abstract ideas. If not, then the patent claims are patent eligible. If the claims are directed to a judicial exception, however, the examination proceeds to the second step of the test.

In the second step, the elements of each claim are considered, "both individually and 'as an ordered combination' to determine whether the additional elements 'transform the nature of the claim' into a patent-eligible application."2This test may sound straight-forward, but its application has been challenging and, at times, controversial.

In the electrical arts, the patent eligibility analysis generally involves the "abstract idea" judicial exception. The Supreme Court's June 2014 decision in Alice v CLS Bank, which helped establish the Mayo/Alice two-step test for patent eligibility, is also the most important case for software and electronics patents. Alice considered the eligibility of patent claims related to methods of mitigating settlement risk in a financial exchange.

The Court found that the claims were ineligible for patenting because they failed to claim significantly more than the abstract idea of intermediated settlement. Significantly, the Alice Court found that the method claims at issue required only a "generic computer implementation" of that abstract idea.3

Following this same line of reasoning, subsequent Federal Circuit cases have distinguished between claims that "focus on a specific means or method that improves [a] relevant technology" (which are not abstract and thus eligible) and claims that are "directed to a result or effect" that simply invoke "generic processes and machinery" (which are abstract and thus ineligible).

For example, the Federal Circuit has found eligible patent claims directed to a system for animating a CGI human to simulate speech, using unconventional "rules" that related subsequences of phonemes, timings and morph weight sets. The unconventional data processing method rendered it more than a generic computer implementation of an abstract idea.4Similarly, the Court has found eligible patent claims directed to an internet content filtering system located on a remote ISP server.

Although the claims only recited generic computer, network and internet components, the specific arrangement of the components was unconventional and led to benefits in implementing the claimed filtering system.5 The Court has also found patent claims eligible when they improve the performance or functionality of computer systems.

In the chemical and biological arts, the most relevant judicial exceptions are those forbidding the patenting of natural laws and phenomena. Thus, naturally occurring organisms and chemical and biological molecules (including genetic material) are not eligible for patenting in the United States even if isolated and/or newly identified.6

Even combinations of such natural compositions or engineered versions of natural organisms or molecules are only eligible for patenting in the United States if that combination or non-natural modification leads to a markedly different characteristic compared to the properties of the natural product.7

The United States has just one policy-based or moral restriction to patenting in the chemical and biological arts, which is a prohibition against patenting humans. Thus, in contrast to many other jurisdictions, patent claims to methods of medical treatment are broadly eligible in the United States, as are claims to pharmaceutical compositions.

That said, patent claims directed to methods of medical treatment have been found ineligible, when deemed broadly directed to a natural law or phenomenon, rather than the application of natural principles to a specific method.

The courts have found treatment method claims ineligible where they were not directed to treating "specific patients using a specific compound at specific doses to achieve a specific outcome."8In practice, though, United States courts take a flexible approach to assessing the specificity of a medical treatment claim.9

By contrast, as in the Mayo decision invoked in the Mayo-Alice test, medical treatment claims that do not require actively treating a patient are deemed improperly directed to a natural law.10 Following (and perhaps expanding upon) this guidance in Mayo, the Federal Circuit has repeatedly, though at times begrudgingly, found diagnostic method claims ineligible for patenting when such methods employ routine or conventional technology, such as PCR amplification or standard immunoassays. even when the methods are believed to be "ground-breaking."11

B. Eligibility Law before the EPO

Questions of subject matter eligibility before the European Patent Office (EPO) are determined by reference to Articles 52 and 53 of the European Patent Convention (EPC) and the associated implementing regulations.

Article 52 EPC limits European patents to inventions that "are susceptible of industrial application," and further excludes from patentability patent claims directed to

"discoveries, scientific theories and mathematical methods … aesthetic creations … schemes, rules and methods for performing mental acts, playing games or doing business, and programs for computers … [and] presentations of information."
Article 52 EPC notes that the stated prohibitions against parenting certain types of subject matter only applies "to the extent [the patent claim] relates to such subject-matter or activities as such."

Article 53 EPC imposes further limits on patent subject matter eligibility based on moral or policy considerations, forbidding the patenting of inventions "contrary to 'ordre public' or morality" or directed to illegal activities, as well as patents directed to "plant or animal varieties or essentially biological processes for the production of plants or animals," and to "methods for treatment of the human or animal body by surgery or therapy and diagnostic methods practiced on the human or animal body."

Under Article 52(2) EPC, the EPO applies a low-level test, based solely on the presence of a physical feature in a claim, to assess whether a claim directed to a computer-implemented invention recites patent-eligible subject matter.

This low-level test is, however, balanced at the inventive step analysis under Article 56 EPC, by a requirement to demonstrate that the claimed invention gives rise to a technical effect. That is to say, the claimed invention must provide a technical solution to a technical problem.12

As the EPO considers that non-technical features do not contribute to the solution of the technical problem, the EPO omits such non-technical features from the inventive step analysis.13 Therefore, the inventive step analysis focuses solely on the technical features of the claimed invention.

Thus, at the EPO and unlike in the U.S., a patent-eligibly hurdle for computer-implemented inventions is easy to overcome, such as by introducing a physical feature into a claim. Most of the analyses performed in the U.S. at the patent-eligibility stage are deferred by the EPO until the inventive step analysis stage.

Further, non-technical features play no role in the EPO's inventive step analysis, unless the applicant can persuade the EPO that such non-technical features interact with the technical features of the claim so as to produce a technical effect, i.e., by its application in the technical solution of a technical problem.

Accordingly, the EPO approach to evaluating patent-eligibility of computer-implemented inventions differs substantially from that of the USPTO. However, the combined patent eligibility and inventive step analyses by the EPO and the U.S. patent-eligibility analyses frequently render substantively similar outcomes, even if for different reasons.

Similar to the computer-implemented inventions, in the chemical and biological arts, patent claims to newly discovered substances are eligible for patenting if they can be demonstrated to have a "technical effect."14 Thus, genetic sequences may be eligible for patenting if they are isolated from their natural environment or derived from a technical process.

Patent claims directed to methods of medical treatment or diagnosis are not eligible for patenting, but claims may be drafted to provide some protection for inventions in these areas.15  For example, a method of using substance x to treat cancer may be patented as "compound x for use in treating cancer." Diagnostic methods are also not eligible for patenting. However, eligible claims can be drafted to protect such inventions by omitting part of the method, typically the final step of attributing a disease diagnosis to the test results.

C. Eligibility Law in Other Jurisdictions

The authors of this article recently collaborated with attorneys in other jurisdictions to write a global guide to subject matter eligibility.16 This work revealed some commonalities in the different approaches to assessing subject matter eligibility. For example, all regions or countries addressed in that publication forbid the patenting of abstract ideas and scientific principles, recognizing that allowing patenting in this area could stifle progress.

Individual jurisdictions take different approaches, however, in distinguishing between patent claims that are improperly directed to an abstract idea or scientific principle and thus not eligible for patent protection and those that instead practically apply such ideas or principles such that they are eligible for patent protection.

This work also revealed sharp differences in the type and extent of specific exclusions from subject matter eligibility in the jurisdictions covered by the publication. For example, some countries, such as the United States and Australia, allow for the patenting of a wide range of subject matter, including methods of medical treatment and genetically modified life forms. These countries also permit business method patents if there is some ingenuity or improvement of involved technology.

Other countries are much more restrictive. China, Israel and Japan generally do not permit the patenting of business methods, by law or by practice, but may allow them in certain cases having a technological implementation and/or improvement. Many jurisdictions, including, Canada, China, Israel, Japan, South Korea and Taiwan do not allow the patenting of methods of medical treatment, though most allow patenting of inventions in this area as "compositions for use" or "Swiss-type" claims.

And India is especially restrictive, specifically forbidding the patenting of business methods, any methods of medical treatment (including 'Swiss-type' use or composition-for-use claims), or other specific subject matter including methods of agriculture or horticulture and integrated circuit topography. And even between countries that seem to allow patenting of certain technology, there may be wide differences in the level of ingenuity or improvement required.

These differences in the assessment of subject matter eligibility can be significant and can impact efforts to protect inventions in multiple jurisdictions. Patent practitioners must carefully consider these differences in their international patenting efforts, including in their selection of an international searching authority and their deference to that authority when patent eligibility objections arise.


1."PCT Yearly Review 2020 — Executive Summary," World Intellectual Property Organization, (2020).

2. Alice Corp. Pty. v. CLS Bank Int'l, 573 U.S. 208 (2014) (quoting Mayo Collaborative Servs. v. Prometheus Lab'ys, Inc., 566 U.S. 66, 78 (2012)).

3. Id. at 221.

4. McRO, Inc. v. Bandai Namco Games Am. Inc., 837 F.3d 1299, 1313 (Fed. Cir. 2016).

5. Bascom Glob. Internet Servs., Inc. v. AT&T Mobility LLC, 827 F.3d 1341, 1350 (Fed. Cir. 2016).

6. Association for Molecular Pathology v. Myriad Genetics, Inc., 569 U.S. 576 (2013).

7. Compare Nat. Alternatives Int'l, Inc. v. Creative Compounds, LLC, 918 F. 3d 1338 (Fed. Cir. 2019) with Funk Bros. Seed Co. v Kalo Inoculant Co., 333 U.S. 127 (1948). Compare Diamond v. Chakrabarty, 447 U.S. 303 (1980), with In re Roslin Inst (Edinburgh), 750 F. 3d 1333, 1337 (Fed Cir 2014).

8. Vanda Pharms. v. West-Ward Pharms., 887 F.3d 1117, 1136 (Fed. Cir. 2018).

9. Nat. Alternatives, 918 F.3d at 1346. Endo Pharm. Inc. v. Teva Pharm. USA, Inc., 919 F.3d 1347, 1353 (Fed. Cir. 2019).

10. Mayo Collaborative Services v. Prometheus Labs., Inc., 566 U.S. 66 (2012).

11. Athena Diagnostics, Inc. v. Mayo Collaborative Servs., LLC., 927 F.3d 1333 (Fed. Cir. 2019) (denying en banc review with four concurrences and four dissents).

12. E.g., Guidelines for Examination in the European Patent Office, Part G, Chapter II, 3.6.

13. See id., Chapter VII, 5.4.

14.G2/88 Friction Reducing Additives.

15.G1/04 Diagnostic Methods.

16.Patent Subject Matter Eligibility: A Global Guide (Paul W. Browning, Christopher C. Johns, & Sara A. Leiman eds., 2021).

Originally published by Westlaw Today

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.