What Can I Patent?

One of the first questions I work through with inventors is whether their invention is even patentable. Not everything can be patented, and understanding the boundaries upfront saves time and money. Here’s a plain-English breakdown of what the patent system protects — and what it doesn’t.

The Four Categories of Patentable Subject Matter

U.S. patent law protects four broad categories of inventions:

• Products: A new and useful physical object or device — anything from a consumer product to an industrial machine to a medical device.
• Machines: A mechanical or electrical apparatus that performs a function. This overlaps significantly with “products” in practice.
• Processes (Methods): A series of steps for accomplishing a result. Manufacturing processes, chemical processes, and software-implemented methods can all qualify as patentable processes.
• Compositions of Matter: Chemical compounds, mixtures, and materials — including pharmaceuticals, polymers, alloys, and other engineered substances.

If your invention falls into one of these categories, it clears the first hurdle. But subject matter eligibility is just the starting point — there are additional requirements to actually obtain a patent.

The Three Core Requirements for Patentability

Beyond falling into a patentable category, your invention must meet three substantive requirements:

• Novelty: Your invention must be new. If the invention has already been publicly disclosed — in a prior patent, a publication, a product on the market, or even your own prior public disclosure — it may not be patentable. This is why filing before any public disclosure is so important.
• Non-obviousness: Your invention must not be an obvious adaptation of what already exists. This is the most subjective requirement and the one that generates the most debate during patent prosecution. An invention can be new but still fail if a person of ordinary skill in the field would have found it obvious to combine or modify existing technologies to arrive at your invention. Arguing non-obviousness with a patent examiner is where experience matters most.
• Utility: Your invention must have a useful, practical application. This is rarely a sticking point for most inventions, but it does exclude things like purely theoretical concepts with no real-world application.

What Cannot Be Patented

Certain categories of subject matter are explicitly excluded from patent protection, regardless of how novel or clever they are:

• Abstract ideas and mathematical concepts: You can’t patent a mathematical formula, a law of nature, or an abstract idea in isolation. However, a practical application of an abstract idea — implemented in a specific, useful way — may still be patentable.
• Laws of nature and natural phenomena: Naturally occurring substances, physical laws, and natural phenomena cannot be patented. However, a new process for using or applying them often can be.
• Purely mental processes: A method that can be performed entirely in the human mind, without any physical implementation, is not patentable.

Can I Patent an Improvement to an Existing Product?

Yes — and this is one of the most common scenarios I work with. You don’t need to invent something entirely from scratch. If you’ve developed a meaningful improvement to an existing product or process, that improvement may be patentable on its own, as long as it meets the novelty and non-obviousness requirements. The key question is whether the improvement would have been obvious to someone skilled in that field given what was already known. That’s a nuanced analysis, and it’s one I help clients work through carefully.

Not Sure Whether Your Invention Qualifies?

Patentability is rarely black and white. A prior art search and patentability opinion can give you a much clearer picture of where your invention stands before you invest in a full application. Schedule a consultation today and I’ll help you evaluate your options. The initial $250 fee is credited toward your work if you move forward.

Related Topics:

• What is a Patent?
• How Do I Patent My Invention?
• What is the Difference Between a Utility Patent and a Design Patent?
• What is a Patent Search?
• What is a Provisional Patent Application?