How do I properly use trademark symbols to give notice of my rights?
It's important to properly use the trademark symbols TM, SM and ® to give notice of your rights. When you do this, it make it harder for a third party to claim it was an "innocent infringer."
To give notice of a registered trademark, you use the ® symbol. Note you may not use this symbol until your mark is registered.
For an unregistered mark used on goods, you use TM, for an unregistered mark used on services you use SM.
An additional attribution statement identifying the mark and the mark owner can be helpful, but is not required.