Abstract
The classification and systematization of the medieval act sourcesis the undeveloped direction in the domestic source studies. The article contains the source study analysis of a special type of act sources, also known in the scientific community as «tarkhanyarlyks». The tarkhanyarlyksare divided into three different subspecies. Moreover, the article provides a lot of scientific facts, that enable the identification of a social group known as «tarkhans». Theirpopulation size, assignment, position and status in the medieval society could be traced in the text of the tarkhanyarlyks. The classification of the tarkhanyarlykson types and subtypes is also of the high importance as it will constitute the expansion of the medieval history sources.