Licensing Structured Data with Ease

In response to the need of a rights expression language (REL), we have proposed LicenseScript, an REL based on multiset rewriting and Prolog. LicenseScript has advantage over existing RELs, in the sense that it has a well-defined semantics. In fact besides semantics, LicenseScript has a lot of other advantages over other RELs. The mission of this paper is twofold: (1) to put a spotlight on these advantages, (2) at the same time justifying some of our design rationales in LicenseScript. We accomplish this by giving examples of licensing models that are greatly facilitated by the use of Prolog as a component of LicenseScript. At the same time showing how LicenseScript makes these non-trivial models viable, we also make LicenseScript a stronger case than it previously might have occurred to be