The issue of copyrights in the age of digital copies and networking technologies has been a thorny one. Copyright holders have developed literally hundreds of different mechanisms by which to prevent unauthorized copying and use of their property, and consumers and users have continued to find ways around these mechanisms both to protect their fair use rights and, in some cases, to abuse these rights. Accordingly, the technology associated with Digital Rights Management (DRM) is in a state of almost constant flux. Even more, because so many different attempts have been made to address this issue, very few DRM technologies can interoperate. An interesting problem, and one that must be addressed if copyright holders can ever hope to effectively protect their rights using DRM.
In the long run, it is not at all clear to me that there is *any* feasible way to use DRM to fully protect the rights of copyright holders in all cases. It may be that fundamental changes in trademark and copyright law are required to take into account the changes in technological infrastructure that have occurred.