A registered trademark is a mark registered with the U.S. Patent and Trademark Office. The artist must file a registration application with the office. After evaluating the application and the mark, the office may allow the artist to register the mark. Registration allows the artist to sue any person or business using the mark without permission throughout the United States.
If an artist uses a unique mark publicly with the "TM" symbol, he creates an unregistered trademark. The use of the symbol tells the public the artist is claiming a trademark. However, an unregistered trademark isn't necessarily enforceable throughout the U.S.; instead, the artist's protection may cover only the geographic area where he's using the mark.
Musicians can trademark their artist name and logo. A musician who builds a fan base under a name that's not trademarked may face difficulty later. For example, a band works for years in a region under a specific name and has thousands of followers. Once the band gets a record deal, the members find they can't use their name because another artist has already trademarked that name. Even if the name is the birth name of one of the band members, another party may have trademarked it previously, preventing the band from using the name commercially. Now the band members have to alter the band name name and spread the word to fans about the difference while trying to create their first major album. Additionally, the musician who owns the trademark could sue the band for trademark infringement. Had the band members tried to trademark the name early on in their career, they would have found the name was already in use and adjusted accordingly.
A visual artist, such as a painter or cartoonist, can register his name as a trademark. This prevents other artists from labeling their work with his name. An artist also could create an unregistered trademark through the public display of his artwork and use of his name to promote himself as an artist. In order to register a trademark or create and enforce an unregistered trademark, the mark must be distinct. A generic mark or mark being used by another artist isn't eligible for protection.
If an artist or musician has been using a name that's already trademarked, he may still have the right to use it commercially. He may challenge the validity of the other artist's trademark registration if the trademark's owner isn't using the mark commercially.