TM stands for trademark. SM stands for service mark. And the “®” symbol means that the trademark is federally registered with the United States Patent and Trademark Office.

There is no registration requirement to use the TM or SM designations. They are used by trademark owners to give notice to others that the owner lays claim to the trademark. Use of the ® symbol however requires that the trademark is registered with the PTO. If you have an application before the PTO, you cannot use the ® symbol. Also, if your trademark is registered with a state secretary of state, but not the PTO, you cannot use the ® symbol.