I don't know for certain. Most of what we do now is copying works that were written when digital rights weren't even contemplated. Most of what we produce now are reproductions of printed materials, textbooks--primary sources.
It's my understanding that the publishing industries are including digital rights and distribution rights as they enter into new contracts with their authors. It remains to be seen how that unfolds in a mobile consumption environment.
We have distributed a number of products that are royalty-free. They were created under Creative Commons licences and so on, and we see those used across the different forms of devices. How the publishers will safeguard those--DRM, digital rights management, and the digital rights, and the measures they put on them to control them--is a function of the publishers' manufacturing, if you will, of those products.