top of page

Beyond Novelty and Obviousness: Other Ways to Invalidate a Patent

Sep 12
6 min read

When most people think about challenging a patent, their mind goes straight to prior art. Find an old document or product that shows the invention wasn't new, or wasn't a real step forward, and the patent falls apart. That's the classic approach, and it gets most of the attention because it's the ground most commonly raised in patent disputes around the world.


But novelty and obviousness are not the only tools available. Patents can be challenged on several other grounds, and in many cases these paths are actually stronger or faster than digging through old technical literature looking for the perfect piece of prior art. Here's a look at the main alternatives, explained in plain terms that apply broadly across different patent systems.


The Patent Doesn't Teach How to Actually Make the Invention

A patent is meant to be a trade. The inventor gets exclusive rights for a period of time, and in exchange, they have to teach the public how to actually build and use what they invented. If the patent document doesn't hold up its end of that bargain, it can be challenged.


This means the description has to be clear and complete enough that someone working in that field could build the invention and get it to actually work, without a huge amount of extra guesswork or experimentation. This ground works especially well against patents that claim very broad or sweeping coverage but only actually show one narrow example of how to achieve it. If a patent claims an entire family of products but only demonstrates a handful of working versions, that gap between what's claimed and what's actually taught becomes a real target.


The Patent Claims More Than It Originally Described

This is a related but separate issue. Even if a patent generally explains how to make the invention, a challenge can arise if the claims, especially ones added or changed later during the application process, cover something broader or different than what was originally put down on paper.


This comes up often when claim language shifts over time, or when a patent holder later tries to stretch old wording to cover a newer product that didn't even exist when the patent was first filed. If the original filing doesn't show that the inventor actually had that broader version in mind at the time, the claim can be struck down or narrowed.


The Claims Are Too Vague or Unclear

Patent claims are supposed to draw a clear line around what is and isn't covered by the patent. If the language used is so vague, confusing, or open-ended that someone skilled in that area can't tell what the patent actually protects, the claim can be thrown out for lack of clarity.


Vague terms like "aesthetically pleasing" or numerical ranges without any explanation of how they should be measured have been struck down for this reason in various jurisdictions. This is a favorite challenge because it doesn't require finding any outside evidence at all. The attack is aimed at the patent's own wording.


The Invention Isn't the Kind of Thing That Can Be Patented

Almost every patent system in the world excludes certain categories from protection altogether, things like abstract ideas, pure mathematical formulas, natural phenomena, and in some places, methods of doing business or simply automating an existing manual process by putting it on a computer.


A patent that just takes an everyday concept, like matching buyers with sellers or managing a schedule, and adds "using a computer" or "over the internet" without contributing anything genuinely inventive on top of that, often won't survive this kind of challenge. This ground has knocked out large numbers of patents in software and financial technology spaces over the past decade. It's attractive to challengers because it can sometimes be resolved early, without expensive searches through old documents or products.


The Wrong People Are Listed as Inventors

Patents have to correctly name everyone who genuinely contributed inventive thinking to the invention, and only those people. Leave someone out who deserved credit, or include someone who didn't actually contribute, and the patent can become vulnerable to challenge.


This issue often surfaces in disputes involving joint research projects, university collaborations, or former employees who claim they were unfairly left off the paperwork. Many systems will allow an honest mistake to be corrected, but if there's evidence the omission was deliberate, it can seriously damage the patent's standing.


The Patent Was Obtained Through Dishonesty

This is one of the more serious grounds, because it doesn't just affect a single claim, it can undermine the entire patent, and sometimes related patents in the same family too. This happens when the applicant or their representative knew about important information, like a damaging piece of earlier work, and deliberately hid it from the patent office while the application was being reviewed.


Most systems set a high bar here. A challenger usually has to show both that the hidden information would have changed the outcome, and that it was withheld on purpose rather than by accident. It's hard to prove, but when it succeeds, the consequences are severe, which makes it a real threat during disputes even though it isn't usually the first strategy reached for.


Overlapping Patents on the Same Invention

Companies sometimes end up with multiple patents that cover very similar ground, whether through deliberate portfolio strategy or just messy filing practices over the years. Many patent systems have rules against a single patent owner getting two patents that effectively cover the same invention, since that would extend their period of exclusivity beyond what's normally allowed.


This kind of challenge compares the claims of two related patents held by the same owner against each other, rather than against outside prior art. If the later patent is just a minor tweak on the earlier one, it can be invalidated or narrowed. This has come up repeatedly in pharmaceutical disputes, where companies have been accused of stacking overlapping patents to delay competition from generic versions of their products.


Arguments Made Earlier Come Back to Limit the Patent

Sometimes a patent doesn't need to be thrown out entirely to lose its bite. If, during the application process, the patent holder narrowed their claims or made specific arguments to get around earlier work, they can later be stopped from arguing that the same claims should be read broadly enough to cover a competitor's product.


This isn't technically an invalidity argument, it's more of a limitation on how the patent can be enforced, but it often produces the same practical outcome. The patent survives on paper but becomes toothless against the very product it was meant to stop. Careful analysis of exactly what the words in the claims mean can accomplish something similar. Sometimes the real fight isn't about whether the patent is valid, it's about what it actually covers, and a narrow reading can make infringement impossible to prove even against an otherwise solid patent.


Choosing the Right Strategy

None of these grounds work best in isolation. A company defending against an infringement claim usually wants speed and lower cost, which makes clarity and subject-matter challenges appealing, since they can sometimes end a dispute early, before expensive fact-finding and expert reports pile up.


A challenger going through a patent office review process, on the other hand, is often more limited in scope. Many administrative review systems only allow challenges based on novelty and obviousness using earlier patents and publications, which means arguments about disclosure, clarity, or subject matter eligibility sometimes have to be saved for a court proceeding instead, where a broader range of grounds is usually available.


The strongest challenges often combine several of these theories at once. A patent might have both a disclosure problem and an obviousness issue, or a clarity problem sitting right alongside a subject-matter question. Raising multiple independent arguments gives a decision-maker several different paths to the same conclusion, which matters because a decision can often be upheld on appeal if any one of the grounds holds up, even if the others don't.


The Bottom Line

Prior art searches will always be central to patent disputes, but treating novelty and obviousness as the only tools available leaves a lot of value on the table. Disclosure and description challenges attack whether the patent ever earned its bargain with the public. Clarity and subject-matter challenges attack the patent's own wording and scope, no outside evidence required. Inventorship and honesty-related challenges go after how the patent was obtained in the first place. And overlapping patent claims or narrow claim readings can neutralize a patent's practical power without ever declaring it technically invalid.


For anyone facing a patent dispute, whether trying to clear the way for a new product or responding to an infringement claim, it pays to look at the whole toolkit before assuming prior art is the only road forward.



This article is for general informational purposes only and does not constitute legal advice. Patent invalidity strategy depends heavily on the specific facts, jurisdiction, and forum involved, and anyone facing an actual dispute should consult a qualified patent attorney.

 
 
 

Comments

bottom of page