Putting a song that is not your own up for download is okay as long as you add a disclaimer.
I see this constantly, and I can't help but wonder if these people actually believe that adding these disclaimers will shield them from liability. They look something like this:
These disclaimers are completely ineffective. They do nothing. It's like when someone says, "No offense, but...." Are you any less offended because a disclaimer was added? No. Same here. Placing a disclaimer somewhere on a pirated music blog or near any shared work not owned by the poster doesn't make the behavior any less infringing.
In fact, adding a disclaimer could actually harm any legal arguments you may have should you be sued. Damages may be reduced if the offender is found to be an "innocent infringer," but these kinds of disclaimers imply that the poster knew what he or she was doing was wrong.
In short: just don't post copyrighted content online that isn't yours without permission. There is no magical set of words that will keep you from being successfully sued for copyright infringement.
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