To discover if a company or brand name has already been trademarked, you'll need to conduct a search of federal and state data banks that list registered marks. You also have to use online search engines to discover any common-law trademarks that aren't registered but are still protected under trademark law.
Search for Exact and Similar Matches
Trademark guards against a company or person using the same or a similar name to identify a line of products and services. When you search for any potential conflict with your planned name, also look for slight misspellings or phonetic spellings. A similar name can still be trademark infringement. The U.S. Patent and Trademark Office examiners can rule in such a case that there’s a “likelihood of confusion” between your preferred name and an existing trademark. If you find a match, examine the trademark's record to determine what type of products or services it protects. If your plan is to use the name to identify the brand of a different type of product or service, it may not be infringement.
Checking Federal Trademarks
The first place you should check for possible conflicts between existing trademarks and your planned company or brand name is with USPTO’s Trademark Electronic Search System. The online search can turn up exact matches and similar terms to the ones you entered that are registered marks or are marks in pending and abandoned applications. If you find a trademark that matches or is similar to your intended name, you can bring up the registration certificate that shows the mark’s ownership, the date first used in commerce, and the mark's purpose. This search also shows the mark's status. You may still be able to use your intended mark if a similar one is abandoned.
Search State Trademarks
Trademarks can also be filed at the state level and, in most cases, with the secretary of state. A company may register a trademark in a single state if its use in commerce is solely within a state. Again, look for trademarks that are the same or similar to the name you intend to use, and identify products or services of the same type that you intend to offer.
Common Law Trademarks
U.S. law does not require trademarks to be registered before they are enforceable. In fact, the law requires trademarks to be used in commerce before they can be registered, though an application can still be filed ahead of time. Because there is no central registry for common law trademarks, it can be difficult to discover possible conflicts. Using common Internet search engines can uncover exact matches, but also check for different spellings of the name, including phonetic spellings, to uncover possible conflicts.
The USPTO cannot do preliminary clearance searches for you, but you may hire an experienced trademark lawyer to conduct the search for you. If you anticipate hiring a lawyer to guide your trademark application through its long and sometimes difficult process, bringing in a lawyer early to do your search can be a reasonable and even economical option in the long run.
Your Search Isn't The Final Say
Your preliminary clearance search will only uncover the likelihood of your company or brand name infringing on an existing trademark. If you apply to register your name as a federal trademark, USPTO examining attorneys conduct their own searches of federal and state trademark databases, and for any common law trademarks. While there’s no guarantee that your preliminary search will lead to approval of your trademark, it does improve your chances and can save you hundreds of dollars in non-refundable application fees and months of waiting if you find a likely conflict.