Bullshit! Derivative works are separate works that receive separate protection under the Copyright Act to the extent that they are different from the original work and to the extent that that difference satisfies the requirements for copyright protection. It is, however, infringement to create a derivative work without the permission of the original author. Then you get into a situation where you own the copyright to the derivative work, but cannot exercise any of the rights of a copyright holder without infringing on the rights of the original holder.