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- 1). Check to see if the business name is registered with the United States Patent and Trademark Office. This office maintains an online, searchable database of all registered trademarks. A trademark that appears there is either federally registered or has a pending federal registration. However, if the name is not listed by the U.S. office, it does not necessarily mean the name is not trademarked.
- 2). Search to see if the trademark is a common law trademark. A common law trademark is one being used by a business or other entity, However, it has not been registered, or has only been registered locally. This is harder to determine because there is no single registry of common law trademarks. Check the trademark registry for your state, then check the registries for neighboring states. Since a trademark does not have to be registered to be valid, a business name may still be valid even if it does not appear in any registries.
- 3). Look at how the business name is being used by the company. If the name is followed by the unregistered trademark symbol--the letters TM written in superscript immediately after the business name--it is being used as a trademark. If the "TM" letter do not follow the business name, and it does not show up in any registries, you can safely assume that it is not trademarked.
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