Why Understanding Patent Infringement Matters
If your company designs new products, develops technology, or even resells goods, understanding patent infringement isn’t optional — it’s essential for survival.
Patents are not just about invention; they are about control. A valid patent gives its owner the exclusive right to make, sell, or use their invention. In business terms, that means a patent defines who can participate in a market — and who gets excluded.
The complexity lies in how courts interpret those rights. Whether you are a business owner in Europe, an entrepreneur in Asia, or a start-up collaborating with manufacturers abroad, understanding what counts as infringement directly affects how safely you can innovate and expand.
This three-part post explains how patent infringement works globally, how interpretation has evolved, and why modern courts now focus less on wording and more on function and intent.
What Counts as Patent Infringement?
In simple terms, patent infringement occurs when someone uses a patented invention without the owner’s permission.
That includes:
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Making or producing the patented item or process
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Using it in business operations
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Selling or offering it for sale
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Importing it into a region where the patent is valid
If you do any of these without a license or authorization, you may be infringing — even if you didn’t know the patent existed.
Example:
A skincare brand in Italy designs unique temperature-controlled packaging for serums. If a similar design has already been patented by another company, producing and selling the new packaging could lead to infringement claims — even if the brand created it independently.
The Two Main Forms of Infringement
Patent law generally recognizes two main types:
1. Direct Infringement
This happens when a person or business performs an act that falls squarely within the scope of the patent’s protection — for example, manufacturing or selling a patented device.
A key point: ignorance is not a defence. Even if a company didn’t realize it was using a patented process, it can still be held liable.
2. Indirect (or Secondary) Infringement
This occurs when someone contributes to infringement by supplying tools, parts, or materials specifically made to be used in a patented invention.
Example:
A factory supplies electronic chips that can only function inside a patented smart home system. Even if the factory doesn’t build the full system, it might still be held responsible for enabling others to infringe.
The Central Role of Patent “Claims”
When a court examines an alleged infringement, it starts with the claims section of the patent.
Think of the claims as the blueprint of ownership — they outline exactly what the inventor protects.
Everything described within the claims is protected; everything outside them is open for others to use.
Example:
If a patent claims “a smartphone case made entirely of recycled materials,” a case made from metal likely doesn’t infringe.
But if the claim says “a smartphone case with an environmentally sustainable composition,” then the definition is broader — and a product made from other eco-friendly materials could still fall under protection, depending on how the court interprets it.
That’s why in patent disputes, a single adjective, verb, or phrase can mean the difference between winning and losing millions.
How Courts Interpret Patent Claims
Courts interpret patents from the perspective of a person skilled in the art — a notional expert who understands the technical field.
This process isn’t limited to reading the words on paper. Judges consider:
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The exact wording of the claims
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The supporting description and technical drawings
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The general knowledge of professionals in that field
This approach is called purposive construction — it means the court interprets a patent by looking at what the inventor intended to protect, not merely the literal language used.
However, this gives rise to a delicate balance:
Should inventors be given broad protection to prevent disguised copying?
Or should patents be interpreted narrowly to give competitors clear boundaries?
This tension defines most modern patent disputes — and over time, courts around the world have evolved from rigid literalism to a more functional, intention-based approach.
Global Context — A Move Toward Balance
Across international patent systems, the trend has been toward finding fairness between two sides:
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Inventors, who need solid protection for their ideas
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Competitors, who need legal certainty to innovate without fear
Modern law recognizes that two inventions don’t need to be identical for infringement to occur. What matters is whether the new product or process performs substantially the same function and achieves substantially the same result.
This global shift has made patent protection more flexible and realistic — especially in industries like biotechnology, electronics, and software, where small technical changes can mask real imitation.
From Literal Words to Practical Meaning
For many years, courts approached patents like contracts: every word mattered, and meaning depended strictly on language.
But as industries evolved — especially in technology, engineering, and pharmaceuticals — it became clear that this literal approach could be unfair. Small changes in wording or design could allow competitors to bypass a patent while still copying the core idea.
Modern law began to recognize this problem and introduced a new concept: “equivalents.”
This approach focuses less on exact wording and more on substance — on whether two products or processes work in essentially the same way to achieve the same result.
The Principle of Equivalents — A Global Shift
The principle of equivalents asks a simple but powerful question:
“Even if the accused product or process is not identical to the patented one, does it achieve substantially the same effect in substantially the same way?”
If the answer is yes, the new product might still infringe — even if it falls outside the literal language of the patent claims.
This principle was adopted to prevent companies from making small, cosmetic alterations to avoid liability while still benefiting from someone else’s invention.
Example:
Suppose a company patents a water filter that uses a ceramic membrane to remove bacteria. Another business releases a filter using a glass membrane that performs the same function in the same way, producing identical results.
Even though the materials are different, the second filter could still be considered an equivalent and therefore infringe the patent.
The “Intention” Behind the Invention
When interpreting claims today, courts aim to understand what the inventor intended to protect.
It’s not about catching competitors for innovation — it’s about stopping imitation disguised as innovation.
The focus is on function, result, and purpose, rather than on the exact materials, shapes, or words used.
This means a business can’t escape liability simply by replacing one component with another if the overall mechanism and outcome are the same.
Example:
Imagine a patented eco-friendly packaging design that uses bamboo layers to preserve temperature.
If another brand creates packaging using compressed palm leaves that function in the same insulating way, the change of material alone may not be enough to avoid infringement.
Balancing Protection and Fair Competition
The principle of equivalents changed the entire philosophy of patent protection.
Instead of treating patents as frozen in words, it recognizes that technology evolves and that imitation can take subtle forms.
However, this flexibility also raises concerns for businesses:
Courts therefore aim to strike a middle path — granting inventors fair protection while ensuring third parties can still innovate responsibly.
In short:
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The patent owner deserves protection for their genuine invention, not just for the literal wording.
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The public deserves clarity about what is and isn’t patented.
The International Context of “Equivalents”
In many countries, international patent frameworks encourage this balanced approach.
The goal is to ensure that patent rights are interpreted consistently across regions, giving global businesses a more predictable legal environment.
The key idea is:
“Patent protection should be fair to the inventor and predictable for everyone else.”
So while no two jurisdictions interpret “equivalents” in exactly the same way, the underlying spirit is the same — protecting real innovation, not just clever wording.
What This Means for Businesses
For entrepreneurs, startups, and established companies alike, this shift means that due diligence is more important than ever.
Before launching a new product, companies should not only check for literal overlap with existing patents, but also consider functional similarity.
Even if your design or process looks different, if it achieves the same purpose in the same way, you could still face infringement risk.
Practical Takeaways:
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Always review patents in detail, not just by keywords or visuals.
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Seek legal advice before using a similar process or component.
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When filing your own patents, draft claims broadly enough to cover possible equivalents.
Q1: Which of the following actions can constitute patent infringement?
Manufacturing, using, selling, or importing a patented invention without permission Using an invention for personal research only, without selling or distributing it Only if the product looks identical to the patented invention
Q2: What is the “principle of equivalents” in patent law?
Even if a product is not identical, it infringes if it performs substantially the same function in substantially the same way to achieve the same result Only applies if the product uses the exact materials listed in the patent claims Means a competitor can freely copy an invention if they change a single word in the patent claims
Q3: How do courts determine if a product infringes a patent?
By examining the patent claims through the perspective of a skilled person, considering function, result, and purpose Only by comparing the exact wording of the patent claims with the product’s description By checking if the product looks exactly like the patent drawings
