The Batin or Batin Sembilan are a sub-group of Malay people that inhabits the interior parts of Jambi province.
There are approximately 72,000 Batin living in the interior of south-central Sumatra. They speak a dialect of the Jambi variant of Malay,Ethnologue report for "Malay, Jambi" but the accent is similar to Minangkabau language.
The Batin are Muslim, but have a matrilineal kinship system, which is similar to Minangkabau than to Jambi Malays.
References
Further reading Nuh, M. Imran (2000) Budaya masyarakat suku bangsa Batin di Kabupaten Bungo Tebo, Propinsi Jambi Proyek Pengkajian dan Pembinaan Nilai-Nilai Budaya Daerah, Direktorat Sejarah dan Nilai Tradisional, Direktorat Jenderal Kebudayaan, Jakarta;