Service mark

A service mark or servicemark, is used in some countries as a trademark to identify a service rather than a product. 
When a service mark is federally registered, the standard registration symbol ® or "Reg U.S. Pat &amp; TM Off" may be used (the same symbol is used to mark registered trademarks). Before it is registered, it is common practice (with some legal standing) to use the service mark symbol ℠ (a superscript SM).