Aboriginal Heritage Laws at work in Boronia Vic, page-4

Traditional owner is a nonsense term for the primitive humans that roamed Australia before Captain Cook arrived. To be a legitimate land owner you would have to produce documentation of your ownership which duly verified that the land that you claimed to posses was acquired by you from the previous owner.
Since there was no previous land owners in Australia the land that the Aborigines claim to own was not able to be claimed and there for Australia was open for colonisation by any body who was able to proceed the colonisation process which began the process of formal land ownership..