Copying is not theft, but copying is not sharing or barter, either.
Copying (Kopieren)
X: A / Y: B --> X: A & B / Y: A & B
Theft (Diebstahl)
X: A / Y: B --> X: 0 / Y: A & B
Sharing (Teilen)
X: A / Y: B --> X: 0,5A & 0,5B / Y: 0,5A & 0,5B
Barter (Tausch)
X: A / Y: B --> X: B / Y: A