Re Mel Bay's copyright of "Twinkle, Twinkle Little Star": Anyone can put a copyright claim on anything. That doesn't mean the claim will stand up in court. It is pretty easy to establish that the "Twinkle, Twinkle" melody was written by Mozart when he was a child. I believe his name for it was "At Your Direction, Mommy" or however one would say that in German.

Mel Bay may in fact own a copyright on a particular arrangement or on its own lyrics, but that copyright would extend only to whatever NEW MATERIAL has been added.

--- Steve