Subject Matter Eligibility

35 U.S.C. § 101 defines what can be patented: 'Whoever 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 therefor, subject to the conditions and requirements of this title.' The four statutory categories — process, machine, manufacture, and composition of matter — are interpreted broadly. What § 101 does NOT cover: abstract ideas, laws of nature, and natural phenomena. These three judicial exceptions were developed by the Supreme Court to prevent patents from preempting fundamental building blocks of science and human ingenuity. The modern framework for analyzing § 101 is the Alice/Mayo two-step test, derived from Alice Corp. v. CLS Bank International (S.Ct. 2014) and Mayo Collaborative Services v. Prometheus Laboratories (S.Ct. 2012). The USPTO's January 2019 Revised Guidance restructured how examiners apply this test, placing greater emphasis on identifying a specific category of abstract idea and on practical application. As of 2024, § 101 remains the most contested threshold in software, business method, and biotechnology patents.

Yes — software can be patented, but only if the claims satisfy § 101 under the Alice/Mayo test. The key question is whether the claims are directed to a specific technological improvement rather than an abstract idea implemented on a generic computer. Software patents that survive § 101 typically: (1) claim a specific technical solution to a technical problem (improved computer operation, reduced memory usage, faster processing); (2) include structural limitations tying the software to particular hardware or data structures; (3) describe operations that could not be performed in the human mind or using pen and paper alone; (4) do not merely apply a known mathematical formula to the general field of computing. Examples of software claims that have survived § 101 post-Alice: claims improving graphical user interface rendering, claims solving specific network security problems through novel cryptographic techniques, claims improving database search efficiency. Claims that repeatedly fail: claims that use a computer only to apply an abstract economic or mathematical concept, claims where every step is conventional and the computer is just a tool, claims that can be performed manually with the same result. The Federal Circuit has issued hundreds of Alice decisions — many 2-1 with strong dissents — reflecting genuine legal uncertainty that legislative reform proposals (such as the Patent Eligibility Restoration Act) have not yet resolved.

The Alice/Mayo framework, as restructured by the USPTO's 2019 Revised Guidance, proceeds in three prongs: Step 1 asks whether the claim falls within a statutory category (process, machine, manufacture, or composition of matter) — nearly all claims pass. Step 2A, Prong 1 asks whether the claim is directed to a judicial exception: an abstract idea (mathematical concepts, methods of organizing human activity, mental processes), a law of nature, or a natural phenomenon. The examiner must identify the specific exception — not just label it 'abstract.' Step 2A, Prong 2 asks whether the claim integrates the exception into a practical application — does it apply the exception in a manner that imposes a meaningful limit on the claim? Indicators of practical application include specific technological improvements to a computer or technical process, application to a particular machine or manufacture, transformation of a particular article, and treatment/prevention of medical conditions. A claim that passes either prong of Step 2A is eligible. Step 2B, reached only if Step 2A fails, asks whether the additional elements beyond the exception individually or in combination amount to significantly more than the exception itself — are they well-understood, routine, and conventional (WURC)? The 2019 Guidance requires examiners to support WURC assertions with evidence; bare assertions are insufficient. This is where most successful § 101 arguments are won.

Responding to a § 101 rejection requires a two-pronged approach — argument and amendment — used strategically. On argument: (1) Challenge Step 2A, Prong 1 — argue that the claim is not directed to an identified abstract idea, law of nature, or natural phenomenon. The examiner must characterize the abstract idea specifically; if the characterization is wrong or overbroad, say so. (2) Challenge Step 2A, Prong 2 — argue practical application: the claim integrates the exception into a specific technical improvement to a technological process or computer functionality. Cite Enfish LLC v. Microsoft Corp. (Fed. Cir. 2016) for software improving computer functionality; McRO, Inc. v. Bandai Namco Games America (Fed. Cir. 2016) for claims using rules to achieve a technologically improved result. (3) Challenge Step 2B — if the examiner asserted WURC activity, demand evidentiary support. The examiner must cite 'official notice' supported by evidence or a published document establishing that the elements are conventional. On amendment: Add technical limitations from the specification that tie the claim to a specific technical implementation rather than the abstract idea broadly. Show that the limitation cannot be performed mentally or with pen and paper. Avoid purely functional language — limitations like 'analyzing data to achieve result X' are more vulnerable than 'a hash table indexed by [specific structure] configured to [specific technical operation].' The January 2019 USPTO Revised Guidance and its October 2019 Update are your primary authorities.

Business method patents are significantly harder to obtain and enforce after Alice v. CLS Bank International (S.Ct. 2014). Many pre-Alice business method patents — especially those from the State Street Bank era (1998–2013) that covered pure financial methods implemented on a computer — are invalid under current § 101 doctrine. However, business method patents are not categorically barred. The question is always whether the specific claim, as drafted, is directed to an abstract idea (the business concept itself) or to a specific technological implementation of the concept. Business method claims that remain viable typically: (1) require specific technical mechanisms, not just a generic computer performing the abstract method; (2) solve a technical problem in computer or network architecture, not just an economic problem; (3) use unconventional combinations of technical elements specific to the claimed implementation. The transition period (2014–present) has produced enormous uncertainty. The Federal Circuit has invalidated dozens of financial and e-commerce patents but upheld others on very similar facts, often by 2-1 margins. Legislative proposals (Patent Eligibility Restoration Act) have sought to eliminate the judicial exceptions entirely, but as of mid-2024, no legislation has passed. If you have a business method patent application, claim drafting around the technical implementation — not the economic result — is essential.