What Is Patent Infringement?

Patent infringement occurs when a third party makes, uses, sells, offers to sell, or imports a patented invention in the United States without authorization from the patent holder. Infringement can also include inducing others to infringe or contributing to an infringement.

Both intentional and unintentional conduct can give rise to liability. Even if a party does not have actual knowledge of the patent, they may still be found liable if they acted with “willful blindness”—knowing a patent may exist but deliberately avoiding confirmation.

For patent owners, infringement may require litigation to protect valuable rights. For accused parties, defending against infringement allegations is equally critical. Patent disputes are often complex, resource-intensive, and strategically important to the businesses involved.

Patent Infringement Litigation Process

A patent infringement lawsuit begins with the filing of a complaint in U.S. District Court, typically where the defendant resides or conducts business. The defendant must respond to the complaint or risk default judgment. The case then proceeds to discovery, where each party requests and exchanges documents, testimony, and admissions relevant to the dispute.

One of the key stages of litigation is a Markman hearing, in which the court determines the legal meaning of specific terms in the asserted patent claims. This ruling significantly influences the outcome of the case. From there, the litigation continues through expert discovery, settlement conferences, pretrial proceedings, and trial.

If the trial does not resolve the dispute, either party may appeal to the U.S. Court of Appeals for the Federal Circuit. From start to finish, a patent infringement case may take several years absent settlement.

Standard of Proof

To prevail, a patent holder must demonstrate infringement by a preponderance of the evidence, meaning it is more likely than not that infringement occurred.

• Literal Infringement: Established when every element of a patent claim is found in the accused product or process.
• Doctrine of Equivalents: Even if not identical, infringement may exist if an element in the accused product performs substantially the same function in substantially the same way to achieve the same result as the patented claim.

Given the technical and legal nuances, patent litigation often requires attorneys who are well-versed in both complex technologies and patent law.

Defenses to Patent Infringement

Not every infringement claim is valid. Defendants may assert a variety of defenses, including:

• Non-Infringement – The accused product or process does not meet the elements of the asserted claims.
• Prior Art – The patent is invalid because the claimed invention was already disclosed to the public before filing.
• Invalidity – The asserted patent fails to satisfy statutory requirements (e.g., lack of novelty, obviousness, or non-patentable subject matter).
• Inequitable Conduct – The patent is unenforceable because of misconduct before the USPTO, such as withholding known prior art or making material misrepresentations.
• Licensing – The accused party may have rights under a valid license.

Defendants may also pursue resolution through arbitration, mediation, or settlement negotiations to avoid prolonged litigation.

Damages and Remedies

If infringement is proven, the court may award:

• Compensatory Damages – Measured by lost profits or a reasonable royalty for unauthorized use of the invention.
• Enhanced Damages – Up to three times compensatory damages in cases of willful or egregious infringement.
• Injunctive Relief – Court orders prohibiting continued infringement and reinforcing the patent holder’s exclusive rights.

Importantly, unless there is egregious personal misconduct, directors and executives of a company are not typically held personally liable for patent infringement damages.

How Loza & Loza LLP Can Help

Patent litigation is among the most technical and high-stakes areas of intellectual property law. Our firm takes a pragmatic, business-focused approach: seeking efficient resolutions where possible while preparing every case for trial. We represent both patent owners seeking to enforce their rights and companies defending against allegations of infringement.

Our team combines litigation experience with deep patent prosecution knowledge, enabling us to understand not just the legal standards, but also the underlying technologies. Whether protecting your innovations or defending your business, we are equipped to safeguard your interests in every stage of a patent dispute.