A patent is a right granted by the federal government to exclude others from making, using, selling, offering for sale, or importing the subject of the patent for a limited period of time, whether it be an invention, process, composition of material, or other patentable article, without the permission of the patent owner. Conduct that interferes with the right of exclusion is called infringement.

Patents are issued by the United States Patent and Trademark Office. However, once a patent is issued, the Patent and Trademark Office has no jurisdiction over the patent or any dispute that may arise because of the patent. Lawsuits to enforce a patent may be brought by the patent owner in the appropriate federal district court. Lawsuits may also be brought in federal district court to challenge a patent issued by the Patent and Trademark Office on the ground that it is not valid. Appeals from federal district court decisions in patent cases are heard by the United States Court of Appeals for the Federal Circuit.


Patent infringement can be found on the basis of a wide variety of conduct, including direct infringement; inducing another to infringe a patent; contributing to the infringement of a patent; making, using, or selling a product made in a foreign country by using a patented process; or making or selling parts of a patented invention to be assembled in a foreign country.

In order to determine whether an item or process infringes a patent, it is necessary to evaluate the patent's claims. A patent claim is one aspect of an invention that is to receive patent protection; thus, every patent must have at least one claim, and many patents have more than one claim. Together, the claims define the boundaries of the protection that the patent provides. If an item has an element or elements that are the same as one or more of a patent's claims, the item is said to come within the claim or claims and thus infringes the patent. If the allegedly infringing item is exactly the same as the patent claim, there is said to be literal infringement. If an item or element of an item is not exactly the same as a patent claim, but differs only slightly from the patent claim, infringement may be found on the basis of the doctrine of equivalents, which simply holds that an infringing item need only be substantially the same as a patent claim and not exactly the same.

If a patent is found to be infringed, the patent owner may obtain an injunction, which is an order from a court that will prevent the infringer from continuing the infringing conduct. A patent owner may also obtain monetary damages for economic losses caused by the infringement. If the infringement is found to be willful, a patent owner may receive an amount three times greater than the actual economic losses that were sustained. Depending upon the circumstances, a patent owner may also be awarded attorney's fees and court costs.

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