“Acquisitive prescription” should be denied as a rule of international law governing the acquisition of territorial sovereignty. It is useless in practice and confusing in theory. Replacing it should be the concepts of “historical title” and “tacit agreement”, which would thus expand the traditional five modes for legally acquiring territory to six. This rearrangement would be useful for us to get a clear and correct understanding of this part of international law, and would thus enable international law to play a positive role in dealing with territorial disputes. It would also prevent, hopefully, an exacerbation of the Diaoyu Islands dispute between China and Japan as caused by a misunderstanding of this part of international law.