Neither the Native Title Act 1993 (Cth) nor the various State and Territory real property Acts adequately address the effect upon native title of the administrative act of registering an instrument creating or affecting ordinary (non-native title) interests in land under the Torrens system of land registration. The possibility that native title qualifies the concept of indefeasibility of title in two situations is examined in this paper. The first possible qualification relates to whether or not registration of a statutory grant of land made pursuant to land rights legislation attracts the indefeasibility provisions of the Torrens statutes vis a vis native title. The second possible qualification stems from the Federal Court decision in Hayes v Northern Territory. It relates to whether or not registration of an invalid 'previous exclusive possession act', which is relied upon to confirm the extinguishment of native title, confers an indefeasible title on the registered proprietor in relation to native title. The practical legal implications of classifying native title as an exception to indefeasibility and as a ground for invoking the deferred indefeasibility theory are considered. Two theoretical rationales underlying a native title exception to indefeasibility are also suggested.