What is Indivision ?
It is the fact that several owners own a property together. The purchase by two cohabitants is found in joint ownership whose share, equal or not, is defined by the contribution.
But this is often the case in an estate where the heirs end up in possession of the patrimony of the deceased until the definitive sale of the property, at which time they will share the fruits of these sales.
An undivided shareholder may want to go out of the joint ownership by selling his shares but must inform the other undivided shareholders by virtue of their right of preemption.