How do you prove that the digital music you own has been legally obtained? How does one establish the proof of purchase for songs bought online?
For music bought from a store like iTunes, you could possibly log in and the account would show past purchases. But what happens when the store shuts down? This is very likely to happen to some of the players in this market anytime now. In such a situation, depending on the DRM technology employed to ‘protect’ the songs:
The songs would continue to work using the credentials already established in the file and verified locally by software/device.
All songs that you purchased from the store would stop working. Or they would stop working the next time you upgrade your PC and/or music player.
If the former is the case, then what if you wrap some music in a forged DRM container that points to a dead vendor? There’s no one around to prove that the DRM container has not been created by said vendor and hence there’s no way to falsify your claim that the music was obtained legally from the vendor who, unfortunately, ceased operations.
In the latter case, your only recourse would be to rip the Audio CDs that you (hopefully) created from the purchased music. If keeping ripped music in such a scenario is acceptable, then you can just as well obtain music from file sharing networks and then claim that your music vendor went belly up.