A trademark, such as a company's logo, is a design, phrase, or combination of the two that identifies your product to the buying public. Using your trademark in commerce gives you certain rights to use it exclusively, but additional protection is granted by law. Laws exist at the state, federal and international levels to help you protect your exclusive right to use your trademark.
Common law trademark rights to exclusive use of a logo are automatically created when you begin using it. These rights prevent anyone else from using the same logo in the same locations where you use it. Anyone using your logo after you establish common law rights to it is infringing on your trademark right, and you can sue for infringement. The court can grant you an injunction against further use of your mark by the infringing individual; it can also grant money damages. Common law rights are only valid within the area where you use your logo, which means others may use it anywhere else without infringing on your rights.
Federal law protects trademarks under the Lahnam Act. The Act creates a registration system for published works, including company logos, through the United States Patent and Trademark Office (USPTO). Prior to registering your logo with the USPTO you must conduct a search of logos already registered to ensure yours is original and not so similar to another that it could create confusion between the two designs. Registration requirements include an application, fee and copies of your logo in a format approved by the office. Once accepted by the USPTO for registration, your rights date back to the date you submitted your application, and are enforceable against infringement within the United States.
States provide for registration of a company logo, usually through the secretary of state's office. Registration requires an application and fee, and copies of your logo in a state-approved format. Registering your logo within any state where you use it in commerce protects from infringement within those states. States differ somewhat as to the length of time state registration is valid, and what compensation a court may order should you successfully sue for infringement.
International trademark rights are governed by the Madrid Protocol, an international treaty with 88 signatory nations, as of February 2013. To request international registration via the Madrid Protocol, you must first register your logo with the USPTO. Once the USPTO grants registration, it transfers your application to the International Bureau of the World Intellectual Property Organization located in Geneva, Switzerland. Each signatory nation to the Madrid Protocol then decides whether to grant protection of your trademark rights within its borders. This process does not require any further application or fee other than that originally submitted to the USPTO. Protection within each Madrid Protocol jurisdiction is subject to the intellectual property laws of that country.