Securing provenance has recently become an important research topic, resulting in a number of models for protecting access to provenance. Existing work has focused on graph transformation mechanisms that supply a user with a provenance view that satisfies both access control policies and validity constraints of provenance. However, it is not always possible to satisfy both of them simultaneously, because these two conditions are often inconsistent which require sophisticated conflict resolution strategies to be put in place. In this paper we develop a new access control model tailored for provenance. In particular, we explicitly take into account validity constraints of provenance when specifying certain parts of provenance to which access ...