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Software Patents: What Can and Cannot Be Patented

April 26, 2026 Aruna 9 min read
are software patents legal — intellectual property law and protection

Software patents are among the most complex and contested areas of patent law. Following the Supreme Court’s 2014 decision in Alice Corp. v. CLS Bank International, the landscape for software patent eligibility changed dramatically, and inventors still ask a blunt version of the question: are software patents legal at all? They are — but eligibility now turns on how the claims are framed. This guide explains the current state of the law, what clears the Section 101 bar and what does not, and how to draft toward protection that survives examination.

Patent eligibility for software inventions is governed by 35 U.S.C. 101, which provides that patents may be granted for any new and useful process, machine, manufacture, or composition of matter. However, the Supreme Court has carved out exceptions: laws of nature, natural phenomena, and abstract ideas are not patentable. The challenge with software patents is that software algorithms can easily be characterized as abstract ideas — a category of judicial exceptions that are not patent eligible.

The Alice decision established a two-step test (building on the earlier Mayo framework) for evaluating software patent eligibility. Step one asks whether the claims are directed to a patent-ineligible concept such as an abstract idea. Step two asks whether the claims add something significantly more — an inventive concept — that transforms the nature of the claim into a patent-eligible application.

What Software Inventions Can Be Patented?

Despite the Alice decision, a wide range of software inventions remain patent-eligible when properly claimed. The key is demonstrating that the claims are directed to a specific technological improvement rather than merely an abstract idea implemented on a generic computer.

  • Specific technical improvements to computer functionality: claims that improve how a computer operates — for example, by reducing memory usage, increasing processing speed, or improving network efficiency — have consistently been found patent-eligible.
  • Novel data structures and architectures: inventions involving new ways of organizing, storing, or transmitting data in ways that produce technical advantages can be patent-eligible.
  • Specific machine implementations: software claims that are tightly tied to specific hardware configurations or that recite specific technical operations on specific types of data tend to survive Section 101 scrutiny.
  • Computer-implemented methods with technical effects: methods that use software to achieve specific, concrete technical results beyond merely performing a business function on a computer can be patentable.
  • Artificial intelligence and machine learning methods: specific training methods, model architectures, and applications that produce technical improvements are increasingly being granted patent protection.

What Software Inventions Cannot Be Patented?

The Alice decision has made clear that certain types of software claims are not patent-eligible, even if the software is useful and even novel.

  • Abstract business methods implemented on a computer: taking a conventional business practice and simply performing it using software does not make it patent-eligible. The classic example from Alice itself — using software to manage settlement risk in financial transactions — was found patent-ineligible.
  • Generic data manipulation: claims directed merely to collecting, organizing, or displaying data using conventional computer elements without a specific technical improvement are generally not eligible.
  • Mathematical algorithms without specific application: pure mathematical relationships and formulas are not patent-eligible, even when implemented in software.
  • Mental processes: methods that could be performed mentally — by a human working through steps in their mind — are generally not patent-eligible even if a computer could also perform them.

The USPTO’s Alice/Mayo Framework in Practice

The USPTO applies the Alice/Mayo two-step framework through its 2019 Revised Guidance on patent subject matter eligibility. Under this guidance, examiners first determine whether the claims are directed to certain groupings of abstract ideas (mathematical concepts, certain methods of organizing human activity, or mental processes). If so, they evaluate whether the claims integrate the abstract idea into a practical application or recite additional elements that amount to significantly more than the abstract idea itself.

Practical application integration can be shown by demonstrating that the claims improve the functioning of the computer itself, improve another technology or technical field, apply the abstract idea with a particular machine that is integral to the claim, or use the abstract idea to transform or reduce a particular article to a different state or thing.

Drafting Strategies for Software Patents

Successfully obtaining software patents requires careful attention to claim drafting strategies that emphasize the technical aspects of the invention.

  • Focus on technical improvements: frame the invention as a solution to a technical problem rather than a business problem. Identify the specific technical improvement your software provides over prior approaches.
  • Recite specific hardware: claims that recite specific processors, memory architectures, network configurations, or other hardware elements are more likely to survive Section 101 scrutiny.
  • Describe specific data operations: rather than claiming the result of a computation, claim the specific steps of the computation in technical terms that show how the invention differs from conventional approaches.
  • Include functional claim language tied to structure: use means-plus-function claiming carefully, and ensure that the specification provides adequate structural support for claimed functions.
  • Draft method, system, and computer-readable medium claims: having all three forms of claims provides broader protection and makes it harder for infringers to argue around all three simultaneously.

Appealing Section 101 Rejections

Section 101 rejections are among the most frustrating in patent prosecution because the legal standards are not always clearly defined. When the examiner and applicant cannot reach agreement on patent eligibility, an appeal to the PTAB or Federal Circuit is sometimes necessary. The Federal Circuit has overruled Section 101 rejections in many cases involving software inventions that produced specific technical improvements, providing useful precedent that can be cited in both prosecution and appeal.

Clients ask the question in exactly those words, so it deserves a direct answer before the nuance: yes. Are software patents legal in the United States? They are. There is no statutory exclusion for software anywhere in the Patent Act. A computer-implemented invention is examined under the same 35 U.S.C. 101 as any other, which permits a patent on any new and useful process, machine, manufacture, or composition of matter.

What trips up software applications is not the statute but a judicial gloss on it. The courts have long recognised three exceptions that are not written into section 101 at all: laws of nature, natural phenomena, and abstract ideas. Software cases live and die on the third.

Alice Corp. v. CLS Bank International, 573 U.S. 208 (2014), set the framework that examiners still apply, extending the approach the Supreme Court had used in Mayo. It is a two-step test. Step one asks whether the claim is directed to a patent-ineligible concept — for software, an abstract idea such as a fundamental economic practice, a method of organising human activity, or a mathematical concept. If it is, step two asks whether the claim elements, individually and as an ordered combination, add an inventive concept that amounts to significantly more than the abstract idea itself. Generic computer hardware performing generic computer functions does not.

The USPTO applies this through the 2019 Revised Patent Subject Matter Eligibility Guidance, now folded into MPEP 2106. In examination practice, step one is split into two prongs: prong one asks whether the claim recites a judicial exception at all, and prong two asks whether the claim nonetheless integrates that exception into a practical application. Prong two is where a great many software claims are saved, and it is the part of the analysis most worth drafting toward.

Federal Circuit case law gives the pattern. In Enfish, LLC v. Microsoft Corp. (Fed. Cir. 2016), claims to a self-referential database table were held not directed to an abstract idea, because the claimed advance was an improvement to the way a computer itself operates. In DDR Holdings, LLC v. Hotels.com (Fed. Cir. 2014), claims survived because the solution was necessarily rooted in computer technology to overcome a problem specifically arising in the realm of computer networks. The through-line is technical improvement. Claims that improve how a machine works tend to hold; claims that automate a business practice on a general-purpose computer tend not to.

So the more useful version of the question is not whether software patents are legal, but which software inventions clear the eligibility bar. The answer is those whose claims recite a concrete technical improvement — reduced memory footprint, lower latency, improved network security, a specific data structure, a particular hardware interaction — described in enough detail in the specification that the improvement is credible.

Europe reaches a similar destination by a different route. Article 52(2)(c) EPC lists programs for computers among things that are not regarded as inventions, but Article 52(3) EPC limits that exclusion to the subject matter as such. The EPO therefore grants patents on computer-implemented inventions that solve a technical problem by technical means, and refuses those whose only contribution is non-technical. In practice a claim drafted around a genuine technical effect is workable in both jurisdictions, which is why the drafting advice below is worth following even for a US-only filing.

One practical note for anyone weighing the cost. Because eligibility turns so heavily on the technical detail in the specification, a software application that was written thinly cannot usually be rescued during prosecution — new matter cannot be added. The eligibility case has to be built into the document on the day it is filed.

How PerspireIP Handles Software Patent Applications

PerspireIP’s attorneys have deep experience preparing and prosecuting software patents across a wide range of technology areas including artificial intelligence, cybersecurity, fintech, e-commerce, telecommunications, and cloud computing. We understand how to frame software inventions in terms that emphasize their technical contributions and survive Section 101 scrutiny. We also know when to fight a Section 101 rejection and when to seek a pragmatic resolution through claim amendment.

Conclusion

Software patents remain available for inventions that demonstrate specific technical improvements beyond merely applying an abstract idea on a generic computer. While the Alice decision created significant uncertainty, proper claim drafting and prosecution strategy can still secure meaningful software patent protection. PerspireIP has the expertise to help you navigate these challenges and build a valuable software patent portfolio. Contact us today to discuss your software invention and develop a patent strategy that works.