This paper proposes a more detailed classification of the legal part of the LADM, ISO 19152, (i.e. interests in land) than possible in the current standard (ISO, 2012) today and is an attempt to raise awareness of the possibilities to further develop the LADMs ‘right’, ‘restriction’ and ‘responsibility’ classes (RRR). The term ‘land’ is here used for land, water and air. The LADM does, in principle, already facilitate the modelling of e.g. informal and customary rights. However, there has, to the authors’ knowledge, not yet been any approach that incorporates non-formal social tenure relationships, such as informal occupation, tenancy based on non-formal and informal rights and customary rights into the LADM. This paper uses the non-formal rights descriptions in the Social Tenure Domain Model (STDM) as an input to further develop the LADM. In this paper the authors base their research on an extended classification of the LADMs RRR classes presented at the FIG Working Week in Nigeria (Paasch et al., 2013). The extension is based on the newly developed Legal Cadastral Domain Model, LCDM (Paasch, 2012a), as a conceptual basis for adding an additional level to the LADM classification. The LCDM states that interests in land can be classified according to whether they are limiting or beneficial to real property ownership. The extended classification is further based on the paradigm that there are two major types of interest in land, privately agreed interests and regulations imposed by a public agency to further the interests of society. This paper contains a discussion on how the legal part of the LADM can be expanded. Furthermore, the “code list” issue addressed in the FIG 2013 Working Week paper is further researched in this paper, e.g. how to develop the code lists for refined LCDM classes (based on specialisations), that could/should be used. The incorporation of a specialized description of non-formal rights in the LADM may be of future value when (if) more detailed information on social tenure land use has to be stored in national or international land administration registers. The LADM allows national specializations to be added to the standard, however, such specializations may be useful when used within a nation, but are of rather limited value when more detailed data of interests in land has to be exchanged internationally. This would require international maintenance of code tables.