Elder brother trying to get share from father's self made property

My grandfather during his life time has equally distributed his self acquired property to his 3 sons. Their names were mutated in revenue records in 1980. My Grandfather died in 1988. Subsequent to his death my grand-mother died in 1993. In evidence to that partition all the brothers of my father got executed a Registered Partition deed dated 12/12/1993. So far as the brothers are concerned there is no dispute. Subsequently, my father acquired huge properties by doing different business. He never took the income derived from the lands given by his father.(Grand Father) My elder brother born in 1980. I was born in 1986. Now, my elder brother has filed suit for partition contending that the property is the joint family property. This is Hindu property. My question: 1. What is the nature of the property, which is in the hands of my father? 2. Will my elder brother have a right to ask for partition of the property during the life time of my father? Thank you, Suresh