Any property acquired by the Hindu great grand father, which then passes undivided down the next three generations up to the present generation of great grand son/daughter.
1. This property should be four generation old.
2. It should not have been divided by the users in the joint Hindu family as once a division of the property takes place, the share or portion which each Coparcener gets after the division becomes his or her self acquired property.
3. The right to a share in ancestral or coparcenary property accrues by birth itself, unlike other forms of inheritance, where inheritance opens only on the death of the owner.
4. The rights in ancestral property are determined per stripes and not per capita. Share of each generation is first determined and the successive generations in turn sub divide what has been inherited by their respective predecessor.
5. Properties inherited from mother, grandmother, uncle and even brother is not ancestral property. Property inherited by will and gift are not ancestral properties.
More over:
Self acquired property can become ancestral property if it is thrown into the pool of ancestral properties and enjoyed in common.
Corollary:
Property gifted by a father to his son could not become ancestral property in the hands of the son simply by reason of the fact that he got it from his father.