The familiar symbol of the capital letter "R" in a circle -- ® -- is primarily used to indicate that a brand name or logo is a trademark registered with the U.S. Patent and Trademark Office. Some foreign countries also use the symbol to indicate trademark registration in that country. It is a violation of federal trademark law to use the symbol in commerce without a valid federal trademark registration.

Federally Registered Trademark

Trademark rights are established by actually using the trademark in commerce, not by registering it formally; however, trademark rights can be significantly enhanced by federal registration. In addition to giving the trademark owner the right to use the symbol ®, federal registration also gives the trademark owner the right to sue an infringer of the trademark in federal court; the right to a legal presumption in any infringement case that the owner of the trademark has the right to use it nationwide; the right to record the trademark with the U.S. registration with the U.S. Customs and Border Protection Service to the importation foreign goods that infringe on the trademark; and the right to use federal registration as a basis for trademark registration in a foreign country.

Claiming Trademark Rights

For trademarks that are not federally registered, the ™ symbol can be used to give notice to the public and business competitors that trademark rights are claimed in a brand name or logo. No filing is required with any state or governmental agency to use the ™ symbol; however, the symbol can be used when a trademark is registered with a state agency, but not federally registered.

Using Trademark Symbols

Federal law does not specify how the ® symbol is to be used in terms of placing it on a brand name or logo. It can be placed in either a superscript or a subscript position near the name of logo. In general, trademark owners place the ® symbol in a superscript manner immediately following the name or logo. The ™ symbol is also placed with the name and logo in the same manner. Either symbol must be readily noticeable with name or logo.

Protecting Trademark Rights

Using the ® symbol will not protect a trademark owner against trademark infringement by a competitor. The symbol simply puts the competitor on notice that the name or logo with the symbol is federally registered. To protect trademark rights, the owner will have to take action to confront infringing activity, such as sending a cease-and-desist letter or suing the infringing competitor in federal court.