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How to perform a trademark search
Conduct an informal search.
Trademarks may either be registered or unregistered. It is usually best to register a valuable trademark, but registration is not required in order to have legal rights over a trademark.
In conducting an informal search on the internet, you are looking to see if the mark you wish to use is already in use as an unregistered mark in your field. It is important to remember that you may be held liable for trademark infringement if you use a mark that another entity is already using, even if that entity has not registered the mark.