1) under section 44 of transfer of property act any co owner can sell his share .
2)there is no legal bar on one of the co-owners of an immovable property transferring his share in the property to an outsider
3) purchaser cannot demand particular portion of undivided land . Transfer of Property Act provides that the transferee of a share of a dwelling house, if he/she is not a member of that family, gets no right to joint possession or common enjoyment of the house. Section 44 adequately protects the family members against intrusion by an outsider into the dwelling house. The only manner in which an outsider can get possession is to sue for possession and claim separation of his share.
4) under section 4 of the Partition Act which deals with partition by transferee of share in dwelling house reads as under:-
"4. Partition suit by transferred of share in dwelling house:- (1) Where a share of dwelling-house belonging to an undivided family has been transferred to a person who is not a member of such family and such transferee sues for partition, the court shall, if any member of the family being a shareholder shall undertake to buy the share of such transferee, make a valuation of such share in such manner as it thinks fit and direct the sale of such share to such shareholder, and may give all necessary and property directions in that behalf."
5) file suit for partition