 Nasution and Lubis are the biggest groups in Mandailing clan.While other groups, such as Pulungan, Harahap, Matondang, Rangkuti, and others are the smaller groups of Luat Mandailing.Harahap and Siregar dwell almost in Luat Angkola, which now belongs to South Tapanuli Regency, situated between Regency and North Tapanuli Regency.