http://spinrdf.org/spl#UnionTemplate
Class 'spl:Union template'

rdfs:Class

This type can be used for templates that serve as the union (or "collector") of other templates. Union templates differ from other templates in that all spl:Arguments are optional. This means that union templates can be declared as subclasses of multiple other templates, yet when instantiated, only some of the arguments defined by the superclasses need to be filled in.

Union template

spin:Template