Patent infringement attorneys deal with people who steal legally protected patented inventions. Examples of patent infringement include using someone else's patented medical formula to create your own cheaper cold medicine, or copying someone's patented software program so that you can build your own. If you have filed a patent and feel that someone is using your invention in an improper way, you need the services of a patent infringement attorney. Patent infringement attorneys know which options and procedures will get the desired outcome for your case (whether it's destroying the competing product, stopping the continued misuse of your invention, or compensation for the improper use of your patented invention). Patent infringement attorneys can also defend your use of materials if someone claims you have infringed on their patented invention.