audiokid, post: 354227 wrote: If you were doing older remixes in a demo, would you send those songs to the same publishing company that handled the particular song or do you think this matters?

The music publishing company owns the right of the song not the recording. So if you are mixing the same song (remixing the old song to create new mix), it is still considered the same song although in different recording. The music publisher still owns the right of the songs you have remixed. So they have the right to licensed it to anyone planning to use the songs (such as a recording label).

However, the owner of the sound recording (the one you have just remixed); is not the music publisher but the persons financing the recording , most likely the recording label. In most cases, the recording label will ask the music publisher for permission to create a cover song; then if permission granted (along with licensing fees like mechanical licensing costs), the re-recording/remixing commenced.

After it is done, the finished recording(new version) will be owned by the recording label and they can sell it in record stores or as a digital download.

Summary:
Owner of remixes/sound recording : recording label
Owner of the song: music publisher/songwriter

How they earn money:
Recording label: recording album, single and download sales.
Music publisher/songwriter: mechanical, performance and synchronization licensing fees (mechanical licensing fees comes from the recording label)

Recommendation: If you have remixed, better contact either the recording producer (assigned by the label) or the music publisher as to how to move forward with the project.

Additional note: In US Copyright, copyrighting a song is different from copyrighting a recording.

Copyrighting a song: The owner (music publisher or songwriter) owns the lyrics and melodies of the song.
Copyrighting a sound recording: The owner (recording label or producer) owns the underlying recording and a specific recorded/mixed version of the song.

What this imply: A specific song, for example "Yesterday" by Beatles is owned by a single publisher/writer-Lennon McCartney, but since there are hundreds of covers for this song, it means there are hundreds of copyrighted sound recording for the song "Yesterday" done by different artist other than the Beatles.

Thank you!