“Philips Shavers”

the creator of the adaptation cannot derive any rights from the copyrighted features or elements that he took over from the original work;

the copyright owned by the creator of the adaptation is limited to those elements that he adds to the original and that pass the work test.

If the adaptation passes the test and also contains sufficient copyrighted traits or elements of the original work, it is both an independent work, copyright in which lies with the creator of the adaptation, and a reproduction of the original work, copyright in which lies with the creator of the original work.

If copyright in the original work and copyright in the adaptation are both in the same hands, that copyright owner may assert both copyrights against a third party that infringes them. However, such cumulative ownership does not mean that copyright in the adaptation also includes copyright in the original work.