Patent Infringement Lawsuits

By Attorney

Once a patent is granted, the owner may enforce it by bringing a patent infringement action (lawsuit) against anyone who makes, uses, or sells the invention without the patent owner’s permission.

Infringement and Invalidity

Normally, when a patent infringement action is filed, the alleged infringer counters by attacking the validity of the patent. Patents may be held invalid on a number of grounds. The most common are if an alleged infringer can show that the invention really wasn’t novel or nonobvious or that the patent examiner simply made a mistake in issuing the patent.

If the defendant is unsuccessful and the patent is not invalidated, the court will take one of two approaches. It may issue a court order (injunction) preventing the infringer from any further use or sale of the infringing device and award damages to the patent owner. Alternatively, the court may work with the parties to hammer out an agreement under which the infringing party will pay the patent owner royalties in exchange for permission to use the infringing device.

Utility Patent Infringement

Infringement of a utility patent occurs when someone makes, uses, or sells an item covered by the claims of an in-force patent without the patent owner’s permission. If a court finds that infringement occurred, a patent infringer can be ordered by a court to stop all infringing activity. Any of the infringers who profited from the infringement may also be found liable for money damages. Only an infringer who had reason to know that a patent was being infringed can be held liable for treble damages as a willful infringer.

Design Patent Infringement

Infringement of a design patent occurs when two distinct standards are met: (1) The Ordinary Observer Test: The court first compares the allegedly infringing device with design patent drawings under the ordinary observer test to determine whether the allegedly infringing design is substantially the same as the patented design; and (2) The Point Of Novelty Test: The court compares the patented design with the prior art to determine the novelty of the patented design. Then, the court determines whether the allegedly infringing design appropriates the novelty. (Lawman Armor Corp. v. Winner Intl)

Infringement Lawsuits

In a patent infringement lawsuit the patent owner alleges that one or more parties (defendants) have, without permission, made, used, or sold an invention protected under a patent owned by the party bringing the lawsuit (plaintiff). Patent infringement actions must be filed in the U.S. District Court within a maximum of six years after the date the infringement occurred—or sooner, if a delay in filing would obviously cause undue hardship to the defendant.

Although it is possible to have a jury trial in a patent infringement case, the judge alone is responsible for interpreting the patent claims. (Markman v. Westview Instruments, Inc.) The judge or jury then examines the plaintiff’s patent and compares the elements recited in its claims with those of the accused infringer’s device or process. On this basis, the judge or jury decides whether the plaintiff’s claims, as interpreted by the judge, cover the defendant’s device or process — that is, fully describe the elements contained in the device or process. If the plaintiff’s claims cover (“read on”) the device or process, infringement is found. If the claims do not cover the defendant’s device or process, then no infringement has occurred.

Even if the claims don’t literally read on the infringing device, the judge or jury could find infringement by applying the doctrine of equivalents: The two devices are sufficiently equivalent in what they do and how they do it to warrant a finding of infringement. Also possible, but extremely rare, is the converse: finding no infringement because the two devices are sufficiently dissimilar in what they accomplish or how they work, even though the claims are the same (in patent speak, the negative doctrine of equivalents).

If infringement is found to exist, the judge may:

  • issue an injunction (court order) preventing further infringement
  • award the patent owner damages for loss of income or for profits resulting from the infringement from the time the invention was properly marked (when the word “patent” and the patent number were affixed to the invention) or from when the infringer was first put on actual notice of the infringement, whichever occurred first, and
  • in the event the infringement was willful or flagrant (it continued without a reasonable defense after notification by the patent owner, or infringement occurred through a direct copying without any ground to believe the plaintiff’s patent was invalid), the court may award the plaintiff three times the actual damages established in court plus reasonable attorney fees.

The Supreme Court has determined that court should not automatically issue an injunction based on a finding of patent infringement. (Alternatively, an injunction should not be denied simply on the basis that the plaintiff does not make, sell, or use the patented invention.) Instead, a federal court must still weigh the four factors traditionally used to determine if an injunction should be granted. (eBay Inc v. MercExchange, L.L.C. 126 S.Ct. 1837 (2006).)

When Defendants Attack

Patent infringement lawsuits are risky for the patent owner, because the defendant will almost always attack the underlying validity of the patent on such grounds as:

  • The invention was obvious or lacked novelty when the patent issued. The defendant proves this by introducing relevant prior art references not picked up by the U.S. Patent and Trademark Office (USPTO) in the course of examining the patent application.
  • The patent application failed to fully disclose the best mode of the invention, as is required by the patent laws.
  • The patent applicant failed to disclose relevant prior art known to the applicant (fraud on the USPTO).

Until the late 1980s, courts ruled against the validity of the patent in over half of all patent infringement cases. Lately, however, under the leadership of the U.S. Court of Appeals for the Federal Circuit, the courts are upholding significantly more patents than they strike down.