On Dependent Ergative Case (in Shipibo) and Its Derivation by Phase

Focusing on the Shipibo language, I defend a simple ''dependent case'' theory of ergative case marking, where ergative case is assigned to the higher of two NPs in a clausal domain. I show how apparent failures of this rule can be explained assuming that VP is a Spell-Out domain distinct from the clause, and that this bleeds ergative case assignment for c-command relationships that already exist in VP and are unchanged in CP. This accounts for the apparent underapplication of ergative case marking with ditransitives, reciprocals, and dyadic experiencer verbs, as opposed to the applicatives of unaccusative verbs, which do have ergative subjects. Finally, I show how case assignment interacts with restructuring to explain constructions in which ergative case appears to be optional.