Infringement analysis determines whether a product or a process directly reads on a claim in a patent. A patent attorney performs the infringement analysis of a product or a process on a patent. Patents are confined to the country of grant; therefore infringement is possible only in the country where the patent is in force.
There are different types of patent infringement. They are direct or literal patent infringement, indirect patent infringement, doctrine of equivalents. Direct or literal patent infringement refers to an infringement when a person makes, uses, sells or offers to sell a patented product or a process without prior permission from the patentee. In case of direct or literal patent infringement the product or the process directly reads on the claim in the patent being infringed. Indirect patent infringement is classified into inducement and contributory infringement. In case of infringement by inducement, a person who induces another person to infringe on a patent will be considered an infringer. In case of contributory infringement whoever supplies a component of a patented product or process, knowing that it may be used to infringe a patent will be considered an infringer.
Even though one avoids direct or literal patent infringement, he/she may still infringe the patent under the "doctrine of equivalents." Under the doctrine of equivalents if an accused product or process obtains substantially the same result, performs substantially the same function in substantially the same way as disclosed in the claims of the patented product or process then the accused product or process infringes on the patented product or process under the doctrine of equivalents.