It is narrated from Sa'id bin al-Musayyib (may Allah have mercy on him) that the Messenger of Allah (peace and blessings be upon him) ruled on pre-emption in houses and lands: "As long as they have not been divided. Once they have been divided and the boundaries in them have been separated, there is no pre-emption in them."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الشفعة / 11562