What Is the Alice/Mayo Test for Patent Eligibility?

The Alice/Mayo test for patent eligibility is a two-step framework courts and the U.S. Patent and Trademark Office use to decide whether an invention can be patented under 35 U.S.C. § 101. It filters out claims that try to lock up laws of nature, natural phenomena, or abstract ideas, while allowing patents on inventions that put those principles to specific, concrete use. The test comes from two Supreme Court decisions: Mayo Collaborative Services v. Prometheus Laboratories (2012) and Alice Corp. v. CLS Bank International (2014). If your application got rejected under § 101, if you are challenging someone else’s patent, or if you are drafting claims and trying to avoid a rejection, this is the framework you have to satisfy.

Where the Test Comes From

Section 101 of the Patent Act says anyone who “invents or discovers any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof, may obtain a patent.”¹ The language is broad, but the Supreme Court has long held that three categories fall outside it no matter how novel or useful: laws of nature, natural phenomena, and abstract ideas.² The Court treats these as the basic tools of scientific and technological work, and worries that granting a monopoly over them would block downstream innovation rather than promote it.

Laws of nature are fundamental physical or biological relationships, like the correlation between a drug’s metabolite levels and its effectiveness. Natural phenomena are things that exist without human intervention. In Association for Molecular Pathology v. Myriad Genetics, the Court held that a naturally occurring DNA segment is a product of nature and not patent-eligible just because someone isolated it, though synthetic cDNA created in a lab is eligible because it does not occur naturally.³ Abstract ideas are the broadest and most contested bucket. The USPTO groups them into mathematical concepts, certain methods of organizing human activity (business practices, contracts, sales, managing personal behavior), and mental processes (observations, evaluations, judgments, opinions).²

Step One: Is the Claim Directed to a Judicial Exception?

The first step asks whether the claim, read as a whole, is directed to a law of nature, natural phenomenon, or abstract idea.² Examiners look at the overall focus of the claim, not just isolated elements. A method that boils down to “observe a natural correlation and adjust treatment” is directed to a law of nature. A claim that describes a longstanding business practice dressed up in computer terminology is directed to an abstract idea.

In Alice, the patents covered a computer-implemented scheme for reducing settlement risk in financial transactions using a third-party intermediary. The Court concluded that intermediated settlement is “a fundamental economic practice long prevalent in our system of commerce,” and adding a generic computer did not change that.⁴ In Mayo, the claims covered methods for determining optimal thiopurine drug dosages by measuring metabolite levels in a patient’s blood. The Court held that the metabolite-to-dosage correlations were laws of nature and the claims were directed to those laws.⁵

If a claim is not directed to any of the three exceptions, the analysis stops and the claim is eligible. Most disputed claims are not so lucky.

Is the Exception Integrated Into a Practical Application?

Even when a claim recites a judicial exception, it can still be eligible if the exception is integrated into a practical application. The USPTO’s 2019 Revised Patent Subject Matter Eligibility Guidance formalized this question as a distinct inquiry that, if answered yes, ends the analysis without reaching Step Two.⁶ This is where drafting choices often decide whether a patent lives or dies.

Several indicators point toward integration:

The claim provides a specific improvement to how a computer functions or improves another technical field.
The claim applies a natural law to effect a particular treatment or prevention of a disease.
The claim uses the exception with a specific machine that is integral to the claim, not just a generic computer.
The claim transforms a particular article or substance into a different state or thing.

What does not count: merely saying “apply it on a computer,” adding routine data-gathering steps, or limiting an abstract idea to a particular field of use without more.²

Step Two: The Search for an Inventive Concept

When a claim recites a judicial exception and does not integrate it into a practical application, the analysis reaches the final question: does the claim contain an inventive concept, something that adds enough to transform it from a patent on a bare principle into a patent on a genuine application? The Supreme Court framed this as a search for “an element or combination of elements that is sufficient to ensure that the patent in practice amounts to significantly more than a patent upon the ineligible concept itself.”⁴

This is where most claims that survive Step One fail. In Mayo, the Court walked through the added steps and found each inadequate. Administering the drug just identified who would care about the correlation. Determining metabolite levels told doctors to use whatever measurement method they wanted, which was standard practice. Adjusting the dosage amounted to telling doctors to think about what the result meant. Nothing in the combination went beyond well-understood, routine activity already common in the field.⁵ In Alice, the computer implementation was purely conventional. Creating shadow accounts, obtaining data, adjusting balances, and issuing automated instructions were things generic computers already did.⁴

The Berkheimer Evidence Requirement

An important guardrail on Step Two came from the Federal Circuit’s 2018 decision in Berkheimer v. HP Inc., which held that whether a claim element is well-understood, routine, and conventional is a question of fact.⁷ An examiner or court cannot simply assert conventionality without evidence, and if a genuine factual dispute exists, summary judgment on eligibility may not be appropriate.

Following Berkheimer, the USPTO requires examiners to back up any finding that a claim element is well-understood, routine, or conventional with at least one of the following: a statement in the patent’s own specification describing the element as well-known, a court decision that previously identified the element as conventional, a publication showing the element is widely prevalent in the field, or a formal statement of official notice that the applicant can challenge.² A single publication is not enough. Applicants who see a blanket conventionality finding have a real basis to push back.

How the Test Plays Out in Software

Software patents take the hardest hits under Alice/Mayo. Code is intangible, and many software claims describe doing something humans already did, only faster or on a screen. Claims that describe collecting data, analyzing it, and displaying results draw heavy scrutiny as abstract ideas unless they solve a specific technical problem in computing.

The dividing line often comes down to “what” versus “how.” A claim that describes the desired outcome without explaining the technical mechanism, what the Federal Circuit calls a results-oriented claim, will almost certainly fail. A claim that spells out the specific technical mechanism has a real chance.

In Enfish, LLC v. Microsoft Corp., the Federal Circuit found software claims eligible because they were “directed to a specific improvement to the way computers operate, embodied in the self-referential table.” The invention replaced conventional database structures with a single table where column definitions were stored as rows within the same table, improving how the computer handled data. The court rejected the notion that all software improvements are inherently abstract, noting that “software can make non-abstract improvements to computer technology just as hardware improvements can.”⁸

Programs that improve network security, speed up processing through a novel algorithm, or reduce memory use by restructuring how data is stored tend to survive. Programs that automate an existing human workflow or reorganize financial information on generic hardware tend not to.

How the Test Plays Out in Biotech and Diagnostics

Diagnostic methods are the hardest category to patent after Mayo. A claim that identifies a correlation between a biomarker and a disease, and then tells a doctor to test for the biomarker and consider the result, recites a law of nature without adding an inventive concept. The extra steps are what doctors were already doing. Diagnostic tests can require enormous investment to develop, but the discoveries they rest on are exactly the natural correlations Mayo puts off-limits. In practice, diagnostic method patents are very difficult to obtain and defend.

Methods of treatment fare better. A claim that applies a natural correlation to deliver a specific drug in a novel dosage, combination, or delivery mechanism can pass because it integrates the natural law into a particular treatment.² The Myriad distinction between naturally occurring DNA and synthetic cDNA follows the same logic: human intervention that produces something genuinely new crosses the line from discovery into invention.³

Drafting Claims That Survive

A few principles run through the claims that have held up:

Claim the technical mechanism, not the goal. Instead of “a method of reducing settlement risk,” describe the specific data structures, processing steps, or system architecture that achieves the improvement. Enfish survived because it claimed a self-referential table structure, not “a better database.”
Show a technical problem and a technical solution. Your specification should explain what existing systems got wrong and how the invention fixes it at a technical level. Courts and examiners look to the specification when deciding whether the claimed elements are inventive.
Avoid purely functional language. “A processor configured to analyze data” tells the examiner nothing about what makes the approach different from every other processor. Describe the specific steps, protocols, or configurations.
Be careful with your own specification. After Berkheimer, examiners can cite your specification against you. If you describe a claim element as “well-known” or “conventional,” you have handed them the evidence to reject it at Step Two.
Use dependent claims strategically. Even if a broad independent claim is vulnerable, narrower dependent claims with specific implementation details may survive.

Pending Legislation That Could Change the Framework

The Alice/Mayo framework has drawn sustained criticism from patent holders, industry groups, and some members of Congress for creating uncertainty about what can be patented. The Patent Eligibility Restoration Act of 2025 was introduced in both the Senate and the House on May 1, 2025, and as of 2026 remains under consideration by the Judiciary Committee.⁹ The bill would replace the judicially created exceptions with narrower statutory ones: only a mathematical formula not part of a useful process or machine, a mental process performed solely in the human mind, or an unmodified human gene as it exists in the body would be ineligible. If enacted, it would significantly expand patentable subject matter, especially for software and diagnostics. Whether it advances is uncertain, and until it does, the two-step test governs every patent application and validity challenge in the United States.

1
Office of the Law Revision Counsel. 35 USC 101 – Inventions Patentable
2
United States Patent and Trademark Office. Manual of Patent Examining Procedure Section 2106 – Patent Subject Matter Eligibility
3
Justia. Association for Molecular Pathology v. Myriad Genetics Inc., 569 U.S. 576 (2013)
4
Justia. Alice Corp. v. CLS Bank International, 573 U.S. 208 (2014)
5
Justia. Mayo Collaborative Services v. Prometheus Laboratories Inc., 566 U.S. 66 (2012)
6
United States Patent and Trademark Office. October 2019 Update – Subject Matter Eligibility
7
Justia Law. Berkheimer v. HP Inc., No. 17-1437 (Fed. Cir. 2018)
8
Federal Circuit. Enfish LLC v. Microsoft Corp., No. 15-1244 (Fed. Cir. 2016)
9
U.S. Congress. S.1546 – Patent Eligibility Restoration Act of 2025