These affiliations cover the monastic ordination lineages of the prātimokṣa precepts (སོ་སོར་ཐར་པའི་སྡོམ་པ།) that were introduced in Tibet. Note that, in the case of individuals assigned here to a vinaya lineage, this always relates to their full ordination lineage བསྙེན་རྫོགས་མཁན་བརྒྱུད།).
For sources on early vinaya sites, see under "Y74: early phyi dar community":https://sakyaresearch.org/place_types/74.