Yes, you can patent software in the United States — but not software as such. The USPTO does not grant patents on code, math, or an abstract business idea dressed up in software language. It grants patents on a specific technical solution to a technical problem that happens to be implemented in software. That single distinction explains almost every allowance and almost every rejection founders run into, and it is the thing to understand before you spend money on a filing.
The Rule That Decides Most Software Cases
US patent law bars "abstract ideas" from patent protection. Examiners apply a two-step test: first, is the claim directed to an abstract idea (a method of organizing human activity, a mathematical relationship, a mental process)? If yes, does the claim add "significantly more" — a concrete, technical improvement rather than generic instructions to do the same thing on a computer?
"On a computer," "over the internet," and "using AI" are not the significant more. A measurable improvement to how a machine works usually is.
What Tends to Qualify
- A compression or encoding method that measurably reduces bandwidth or storage.
- Sensor signal processing that separates a real signal from noise in real time.
- A wireless protocol change that extends battery life in a connected device.
- A control algorithm that stabilizes a motor, a drone, or a thermal system.
- A calibration routine that makes a cheap sensor perform like an expensive one.
- A memory or scheduling technique that makes a constrained processor do more.
What Tends to Get Rejected
- "A system that recommends products to a user based on their history."
- "A platform that matches service providers with customers."
- A financial or scheduling calculation moved from paper to a screen.
- A user interface layout with no underlying technical mechanism.
The pattern is consistent: the closer the software sits to hardware, signals, sensors, and system resources, the stronger the case. Software that controls a physical product is a classic candidate — which is why in smart-product projects the protected invention is usually the whole hardware-plus-firmware combination, not the code file.
Drafting Changes the Outcome More Than the Invention Does
Two applications describing the same underlying work can end in opposite places depending on how the technical problem was framed and how the claims were structured. A claim written as "a method of determining X" reads as a mental process. The same work written as "a method of operating a sensor node, comprising sampling at a first rate, detecting condition Y, and switching the radio to a second duty cycle" reads as a machine improvement. This is specialist drafting work, and it is where the money in a software filing actually goes — see our breakdown of what a patent costs in the US and the difference between a patent attorney and a patent agent.
Because filing publishes your method to the world eighteen months in, run a prior art search first. If your technique already exists in an academic paper or an expired patent, you will find out for a fraction of the cost of an office action.
Software Rarely Has Only One Protection Option
If a patent is not the right instrument, you are far from unprotected:
- Copyright — your source code is protected against copying automatically, at no cost, from the moment it is written. Registration adds enforcement teeth but is not required for the right to exist. It protects the expression, not the idea.
- Trade secret — an algorithm running on your own server is never disclosed to anyone. For server-side logic, secrecy is often stronger than a patent, which trades disclosure for a time-limited monopoly. It requires real hygiene: access control, NDAs, and employee agreements. See trade secret vs patent.
- Trademark — the brand keeps its value even after competitors match your feature list. Start with trademarking a product name.
- Execution — release speed, accumulated data, integrations, and an installed base are genuinely defensible in software, and they compound while a patent sits in examination.
Our overview of patent vs trademark vs copyright shows how the three fit together.
What About Apps?
A mobile app on its own is usually a weak patent candidate, because most apps are a screen layer over a known service. The exceptions matter, though: an app doing on-device signal analysis, low-power wireless coordination with a device, or novel sensor fusion is doing technical work. If your app is the interface to a physical product, look at protecting the system — device, firmware, and app behavior together. Medical software carries its own separate track; see software as a medical device.
A Practical Sequence
- Write down the technical problem in engineering terms, not marketing terms.
- Identify what measurably improves — speed, power, accuracy, bandwidth, cost.
- Search prior art before spending on drafting.
- Decide patent versus trade secret based on whether the method is visible in your shipped product.
- If filing, consider a provisional application to secure a date while the implementation matures.
Projects House is an engineering firm, not a law firm. This article is educational and is not legal advice — have a registered US patent attorney or patent agent review your specific case before you file or rely on any strategy here. More background lives in our patents and intellectual property hub.
Building a product where the software and the hardware are inseparable, and unsure what is actually protectable? Contact Projects House — we will help you describe the technical invention clearly enough that your patent counsel can work with it.