Key Takeaways

  • A Section 101 patent determines whether an invention qualifies as patentable subject matter under U.S. law.
  • Patentable inventions must fall into one of four statutory categories: process, machine, manufacture, or composition of matter.
  • Courts have carved out exceptions—laws of nature, physical phenomena, and abstract ideas—which cannot be patented by themselves.
  • The Alice/Mayo test is used to analyze whether a claim involving an exception includes “something more” that makes it patent-eligible.
  • Patent eligibility is distinct from novelty or non-obviousness, but these factors can influence examiners in close cases.
  • Understanding recent case law and USPTO guidance is critical to overcoming Section 101 rejections.

A Section 101 patent refers to a type of patent issued to an inventor of a useful machine, process, manufacture, or composition of matter. It is important for inventors or commercial entities to obtain a Section 101 patent because it gives them the right to exclude other individuals or entities from producing, using, or selling their patented inventions for a certain amount of time.

What Subject Matter Is Patentable Under a Section 101 Patent?

If you plan to apply for this type of patent, you must ensure your invention belongs to one of the statutory categories that are patentable under Section 101. Also, it must not be one of the judicially recognized exceptions.

In an effort to promote the advancement of science and useful arts, the United States Congress defined the subject matter patentable under Section 101 as any new and useful machine, manufacture, process, or composition of matter; or any new and useful improvement to an existing invention under those categories. Any invention that meets the subject-matter requirement may be patented under Section 101. To be eligible, an invention must meet two subject-matter criteria:

  • The invention must fall under one of the four statutory categories of invention.
  • The invention must not be entirely a subject matter that encompasses a judicially recognized exception.

Key Court Decisions Shaping Patent 101 Eligibility

Patent 101 has been shaped heavily by judicial interpretation. The Supreme Court has clarified boundaries in cases such as:

  • Diamond v. Chakrabarty (1980): Held that genetically modified organisms could be patentable, reinforcing that “anything under the sun made by man” may qualify.
  • Mayo Collaborative Services v. Prometheus Laboratories (2012): Struck down claims on diagnostic methods that merely applied natural laws without additional inventive steps.
  • Alice Corp. v. CLS Bank International (2014): Established the two-step test for determining patent eligibility of claims that involve abstract ideas.

These cases illustrate that while Section 101 is broadly worded, judicial exceptions significantly restrict patentable subject matter.

What Are the Statutory Categories of Invention?

  • Process: A mode of treatment of materials for producing a given result. A process can be an act or series of acts performed on the subject matter to reduce or transform it into a different thing or state.
  • Machine: A concrete object that consists of components, devices, or a combination of devices, including all mechanical devices or combinations of mechanical devices and powers necessary for performing a certain function and producing a desired result or effect.
  • Manufacture: A manually or mechanically produced article that is made of raw or prepared materials and gives those materials new forms, properties, qualities, or combinations.
  • Composition of matter: A composition of two or more substances or a composite article that results from chemical union or mechanical mixing, regardless of whether they are gases, fluids, solids, or powders.

Modern Applications of the Statutory Categories

The statutory categories are applied to a wide range of technologies:

  • Software and Business Methods: Although software can fall within the “process” category, courts often find claims ineligible if they simply automate an abstract idea.
  • Biotechnology: Gene editing and diagnostics can qualify as compositions of matter or processes, but they must show more than reliance on natural laws.
  • Engineering and Electronics: Devices and manufactured articles, from semiconductors to medical devices, generally fit into “machine” or “manufacture” categories.

Applicants should draft claims carefully to ensure their invention clearly aligns with a statutory category, reducing the risk of rejection.

What Are the Judicially Recognized Exceptions?

Judicially recognized exceptions include the following:

  • Physical phenomena.
  • Laws of nature.
  • Abstract ideas.
  • Certain practical applications of judicial exceptions.

Physical phenomena, laws of nature, and abstract ideas are the three exceptions to the broad patent-eligibility principles of Section 101. Although they are ineligible for patenting, products and methods that employ them to perform a useful function in the real world may be eligible.

When evaluating whether a claim fulfills the requirements of Section 101, the claim must be regarded as a whole in order to determine whether it is used for a specific application of physical phenomena, law of nature, or abstract idea, and not for the physical phenomena, law of nature, or abstract idea itself.

Besides physical phenomena, abstract ideas, and laws of nature, judicially recognized exceptions have also been described using other terms, such as:

  • Scientific principles.
  • Natural phenomena.
  • Disembodied concepts.
  • Mental processes.
  • Systems that solely depend on human intelligence.
  • Disembodied mathematical algorithms.
  • Formulas.

By establishing these exceptions, the courts show their view that the fundamental tools of technological and scientific work cannot be patented.

The Alice/Mayo Test Explained

When a claim involves one of the judicial exceptions, examiners apply the Alice/Mayo test:

  1. Step One – Identify Exception: Determine if the claim is directed to a law of nature, natural phenomenon, or abstract idea.
  2. Step Two – Search for “Something More”: Assess whether the claim includes additional elements that transform the exception into a patent-eligible application.

For example, merely implementing an abstract idea on a generic computer is insufficient. However, claims that integrate an abstract idea into a practical technological solution may be eligible.

How Does One Deal With an Ineligible Subject-Matter Rejection?

A Section 101 rejection occurs when a patent examiner finds a claimed invention ineligible for patenting. Technically, patent eligibility is different from novelty or non-obviousness, but an invention's novelty and non-obviousness may improve its eligibility.

Step 1: Determine whether the claimed invention is a machine, manufacture, process, or composition of matter.

  • If it is not, then it is not a qualifying subject matter.
  • If it is, proceed to the next step.

Step 2A: Ascertain whether the claimed invention is a judicially recognized exception, that is, a natural phenomenon, law of nature, or abstract idea.

  • If it is not, the claim is a qualifying subject matter.
  • If it is, proceed to Step 2B.

Step 2B: Determine whether the claimed invention recites additional elements that significantly exceed the judicial exception.

  • If it does, the claim is not an eligible subject matter.
  • If it does not, the claim is a qualifying subject matter.

USPTO Guidance and Examiner Practices

The USPTO regularly issues guidance to help examiners apply Section 101 consistently. Recent updates encourage examiners to:

  • Consider claims “as a whole,” not just individual elements.
  • Look for integrated practical applications rather than dismissing claims as abstract.
  • Provide applicants with clear explanations for rejections, giving them a better chance to respond effectively.

Applicants can respond by amending claims to highlight inventive concepts, providing technical explanations of improvements, or citing relevant case law and USPTO guidelines.

Frequently Asked Questions

1. What does Section 101 of the Patent Act cover?

Section 101 defines what types of inventions are eligible for patent protection—machines, processes, manufactures, and compositions of matter—subject to judicial exceptions.

2. Why are abstract ideas not patentable?

Courts view abstract ideas, natural laws, and phenomena as fundamental tools of science that must remain free for all to use. Only practical applications of these concepts may be patented.

3. How can I overcome a patent 101 rejection?

You can argue that your claim fits a statutory category, amend claims to add inventive elements, or demonstrate that your invention provides a technical solution beyond an abstract concept.

4. What is the Alice/Mayo test?

It’s a two-step analysis: first determine if a claim is directed to an exception, then decide if it contains additional inventive features that make it eligible.

5. Does Section 101 affect software patents?

Yes. Many software patents face 101 rejections for abstractness. However, software that improves computer functionality or solves a technical problem can still be patentable.

If you need help understanding or applying for a Section 101 patent, you can post your legal need on UpCounsel's marketplace. UpCounsel accepts only the top 5 percent of lawyers to its site. Lawyers on UpCounsel come from law schools such as Harvard Law and Yale Law and average 14 years of legal experience, including working with or on behalf of companies like Google, Menlo Ventures, and Airbnb.