(=> (Activity-Owner ?Actor) (Exists (?Activity-Ownership) (And (Activity-Ownership ?Activity-Ownership) (Owning-Actor ?Activity-Ownership ?Actor)))) (=> (Owner ?Owner) (Exists (?Ownership) (Owning-Actor ?Ownership ?Owner)))
(<=> (Activity-Owner ?Actor) (And (Actor ?Actor) (Exists (?Activity-Ownership) (And (Activity-Ownership ?Activity-Ownership) (Owning-Actor ?Activity-Ownership ?Actor))))) (<=> (Owner ?Owner) (And (Actor ?Owner) (Exists (?Ownership) (Owning-Actor ?Ownership ?Owner))))