Sir, my father was allotted a site in Bengaluru in 1958 by CITB. He transferred it to his father in

Sir, my father was allotted a site in Bengaluru in 1958 by CITB. He transferred it to his father in law within 4 months through a note written and signed by the chief executive engineer of CITB. The transferee never got the property registered to his name in any sub registrar office. The process of registration does not appear in the EC. The transferee willed the property to his son, without giving anything to either of his daughters. One daughter is my mother. (will not registered) before passing away in 2002. The son (my mother's brother and my uncle) got the site registered to his name in 2009 without the consent of my father who was the original allottee. (my parents and uncle are no more) My question is, do we the children of the original allottee have any rights over the property, as my grandfather never got it registered to his name? Can we claim it back saying that the property never belonged to my grandpa and so he couldn't will it.