It will be interesting to see how the court will determine if its one work or two separate works, and if they will look at other copyrighted media. There is already a rather established model for music video, where even if you have rights to distribute a particular song, you need additional rights to adapt the music to moving images.  On the other side of the argument, there is cases that has addressed compatibility. There were for example gaming consoles that had unlicensed third-party modules that courts deemed to be non-infringing.<p>A key argument I was missing in the article here was the question about market impact. In every court case I have read that talked about derivative works, they always considered the impact that the claimed infringement has on the original work. Court seems to have a historical viewed that copyright is there to protect the authors, and thus leans towards decision that minimize harm. In the case of VMware, it would be interesting to see such arguments from both parties.