A patent attorney is a lawyer that is licensed to practice in front of the United States Patent and Trademark Office (USPTO). In order to sit for the patent bar exam, an attorney must have a technical background approved by the USPTO, for example, an engineering degree. The requirements for registering for the patent bar examcan be found on the USPTO website.
I am a registered U.S. patent attorney living and working in Chicago, IL. Although my law office is in Chicago, my clients are located around the world.