None. you wouldn't copyright the copyright symbol, you would trademark it.

The copyright symbol consists of a C in a circle has become a widely recognised symbol. The copyright symbol was first used in section 18 of the 1909 American Copyright Act.

The law has changed and the copyright symbol is no longer needed to insure the protection of the copyright owner. The symbol for copyright is: ©

it means copyright

it's the symbol for copyright

The copyright symbol looks like a lower case c with a circle around it. ©