A sound recording copyright is the copyright that protects just the recording of a song.
Anytime you have a sound recording copyright, also known as a "master," you are dealing with two separate copyrights. One is for the underlying composition - the song, and the other one is for the recording of that song.
The copyright for your song itself is represented by a "c" with a circle around it. It looks like this:
And the copyright for your sound recording is represented by a "p" with a circle around it. It looks like this:
The "p" stands for "phonogram."
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