Service mark symbol
The service mark symbol, designated by ℠ (the letters SM written in superscript style), is a symbol commonly used in the United States to provide notice that the preceding mark is a service mark.
This symbol has some legal force, and is typically used for service marks not yet registered with the U.S. Patent and Trademark Office; registered service marks are instead marked with the same symbol used for registered trademarks, the registered trademark symbol ®. The proper manner to display the symbol is immediately following the mark in superscript style.
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