Ever get an email like that after posting your own music? I get them all of the time. When I first saw this, I was all confused… I knew this was my original work! How can someone else have a copyright claim on my music?!
Generally, it is not something to worry about. If, like a lot of indie musicians out there, you are using CDBaby to distribute your music, you most likely then signed up for Sync Licensing when you distributed your music there. The link there to Sync Licensing will take you to this page under your artist account, which explains more on how it works:
In fact, if you scoll down to the bottom of that page, you will see this important notice:
Important note for YouTube users: If you log into your YouTube account and see a copyright notice next to your videos, don’t worry! CD Baby will collect money for the usage of your music in videos (this includes videos you upload). This notice means the content ID system identified your song and it’s now setup to generate revenue for that video. You don’t need to take action. CD Baby is not claiming ownership of your song.
See? all should be just fine. This confused me when I first saw it… so hopefully this post helps another artist along the way.