Primitive Ovoids in O+8(q)

Kleidman (1988) has classified the 2-transitive ovoids in finite polar spaces. We show that any ovoid O in O+8(q) for which Aut(O) permutes the points of O primitively, is either the Cooperstein ovoid in O+8(5), or is 2-transitive (and so appears in Kleidmanʹs list).