Talk Abstract: One of the most influential proposals for explaining the occurrence of null arguments in Mandarin object positions is the True Empty Category (TEC) approach, which suggests the existence of a last-resort D head that carries only a case feature and derives its content through LF copying. I present challenges to this approach both at the generalization level and at the theoretical level, and I argue that the empirical evidence supporting TEC can be accounted for by the existing ellipsis mechanisms in Mandarin.