Copyright holders of sheet music are the ones who wrote out the notes. So if I listen to a recording and write the notations on paper or on my computer as MIDI data (that's what they do nowadays anyway) and print it out using some program designed to do just that, the edition belongs to me. Of course the music itself doesn't "belong" to me, but the laid out score and it's copyrights do. Probably if you, mound, bought the sheet music for this, you paid for the material to the publisher and/or for the work of constructing the layout to the editor/creator of the sheet.