Patent infringement
Unauthorized use of a patented invention without the holder's permission.
Patent infringement is the unauthorized making, using, offering for sale, selling, or importing of a patented invention without permission from the patent holder. When the patent covers a process, infringement includes using, offering for sale, selling, or importing the product obtained by that process. Permission is typically granted through a license, and the definition of infringement may vary by jurisdiction.
- field
- Intellectual property law
- known_for
- Unauthorized exploitation of a patented invention without the patent holder's permission
- legal_basis
- Defined by patent claims; territorial in nature
- common_defenses
- Non-practice, non-infringing territory, expired patent, invalid patent, licensed use
Lore & Background
Patent infringement occurs when a party other than the patentee or licensee manufactures, imports, uses, sells, or offers for sale patented technology without permission during the patent's term and within the country that issued the patent. The scope of protection is defined by the patent's claims, and infringement is determined by whether the accused product or method falls within one or more of those claims. If all elements of a claim are present, the claim 'reads on' the technology; if any element is missing, literal infringement generally does not occur unless the doctrine of equivalents applies. In response to allegations, an accused infringer may assert that it was not practicing the patented invention, that no infringing act occurred in the patent's territory, that the patent has expired, that the patent is invalid, or that a license has been obtained. Parties may also settle disputes through licensing agreements, though private settlements may not always serve the public interest because litigating disputes to completion can clarify patent limits or encourage wider use of the innovation. Certain jurisdictions recognize indirect infringement, which can occur when a device is claimed in a patent and a third party supplies a product that can only reasonably be used to make the claimed device. Clearance searches, also called freedom-to-operate searches, are performed on issued patents or pending applications to determine if a product or process infringes any claims, and may include expired art in the public domain. Clearance opinions and validity opinions are legal analyses provided by patent attorneys, often sought before litigation.
Reader's Guide
Patent infringement is a central concept in patent law, defining the boundary between the exclusive rights of a patent holder and the freedom of others to operate. Its significance lies in enforcing the territorial and claim-based nature of patents: infringement is only possible in a country where a patent is in force, and the claims of the patent inform the public of what is prohibited without permission. The doctrine of equivalents and indirect infringement expand liability beyond literal claim reading, while defenses such as invalidity or expiration provide checks on overreach. Clearance searches and opinions help innovators avoid infringement, but the costs of such analyses can be substantial. The existence of patent infringement insurance reflects the financial risks involved, though studies have noted that voluntary insurance schemes may be inadequate. Overall, patent infringement law balances the incentive to innovate against the need for clarity and public access to technology.
Did You Know?
- Patent infringement is only possible in a country where a patent is in force; patents are territorial.
- A clearance search, also called a freedom-to-operate search, may include expired art that acts as a 'safe harbor'.
- Indirect infringement can occur when a third party supplies a product that can only reasonably be used to make a claimed device.
Frequently Asked Questions
What is patent infringement?
It refers to exploiting a patented invention—by making, using, selling, offering for sale, or importing it—without obtaining authorization from the patent owner. The core idea is that someone is benefiting from a protected invention outside the scope of a valid license.
What specific actions constitute patent infringement?
Beyond simply manufacturing a patented product, the act extends to using it, putting it up for sale, actually selling it, or bringing it into a country. If the patent protects a manufacturing process, handling the resulting product can also trigger infringement.
What are the most common defenses raised against a patent infringement allegation?
Defendants often argue the patent has expired, that it was never valid to begin with, or that they held a proper license. They may also point to non-practice of the patent or show the activity occurred outside the patent's territorial reach.
On what legal basis is patent infringement determined?
The scope of protection is anchored in the specific claims written into the patent document, and the right is strictly territorial—meaning it only applies within the jurisdiction that granted the patent. Different countries can therefore reach different conclusions about whether the same act is infringing.
Why does patent infringement matter in civil law and remedies?
It sits at the heart of intellectual property enforcement, giving patent holders a civil cause of action to stop unauthorized exploitation and seek damages. Understanding the boundaries of infringement and available defenses is essential for both rights holders and potential accused infringers navigating disputes.
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