If the proeprty is not registered on your name, instead if the same has been registered on your father's name, then it becomes your father's own and absolute property.
On the basis of the evidences in your possession you can claim the title to the proeprty by filing a suit for declaration and possession of the property or to direct the other shareholders to refund your invested money with interest till this date.
This is the legal step if you want to approach court of law for partition and distribution of the assets left behind by your parents on their intestate death.
If your parents are alive then they can make a family settlement/arrangement based on the investment made by each towards the purchase of this property.
Alternately you people can discuss the issues on this and decide amicably without involving a lawyer or any other outsider and distribute the property or the sale consideration amount as agreed by all.
If you are looking for a legal solution then you may have to approach court and have to wait for years for the dispute to be settled by court.