Over the past decade, numerous countries and researchers have been investigating the potential of 3D cadastre based on the Building Information Model (BIM). In Türkiye, the General Directorate of Land Registry and Cadastre (GDLRC) has been engaged in the “Production of 3D City Models and Creation of 3D Cadastral Bases Project” since 2018. One of the objectives is to develop 3D (physical) digital building models (and databases) through the digitization of floor plans of architectural drawings. In order to ensure the long-term viability of this project, a new regulation was issued in 2021. This regulation mandates the submission of 3D digital building models to the land registry in order to register condominiums. The future goals of the GDLRC include utilizing the 3D digital building models produced to create legal spaces in condominium buildings for the 3D cadastre. However, no research has yet been carried out for this goal. The objective of this research is to identify the legal and BIM data requirements for deriving legal spaces in condominium buildings, in light of the legislative analysis, and to develop a web-based 3D cadastre visualization prototype (showing both legal spaces and physical objects) based on the requirements obtained from the scientific literature. The result of this research demonstrates that well-structured and annotated BIM data can be used to develop a 3D cadastre prototype that meets the legal requirements in the case of Türkiye. Moreover, it is evident that, although the GDLRC has initiated the construction of a robust foundation for a 3D cadastre based on BIM, further enhancements and resolutions must be implemented from a legal and technical standpoint. It is postulated that the identified requirements and the proposed methodology in this research may assist decision-makers in Türkiye and globally in formulating their strategic plans for a 3D cadastre.@en

Spatial planning is a critical element of Land Administration (LA), involving the assessment and management of land use, development, environmental protection, and the optimal utilization of land resources. Recognizing the significance of integrating spatial planning information into the Land Administration Domain Model (LADM) framework, LADM Edition II introduces a dedicated part for spatial plan information -Part 5. This paper delves into the conceptualization and development of the LADM Part 5 – Spatial Plan Information country profile for Greece (GR_SP_LADM). The development of this profile aims to enhance the applicability of LADM Edition II Part 5 and to support better planning, monitoring, and management of spatial data in alignment with Greek regulations.

Spatial planning in Greece operates on multiple levels—national, regional, and local/municipal—each corresponding to different scales of implementation. The national level offers broad spatial guidelines, while the local level focuses on community-specific planning, which may encompass one or more municipalities or even regional or hyper-local areas. Given the complexity of spatial planning processes in Greece, standardization is vital for ensuring interoperability across the different hierarchical levels of government and stakeholders. This paper aims to make the organization of spatial planning-related information in Greece more efficient and transparent, thereby promoting sustainable growth and urban development using consistent spatial data structures and clear legal and administrative procedures.

Therefore, the paper examines the country profiles of LADM Part 5 that have been developed (as in the case of Indonesia, Turkey and others), with a focus on the current state and evolution of spatial planning in Greece. It maps the existing spatial planning framework against the concepts and classes of LADM Part 5, resulting in the development of a tailored country profile for Greece. This profile is illustrated through UML diagrams and at the next step of this research, it will be implemented in a database and validated through instance-level diagrams and practical implementation using 2 case studies. Future work includes the comparison of the country profile for LADM Part 5 for Greece, with the profile developed for Turkey using corresponding use cases.@en

Evaluating the performance of a land administration system (LAS) is a critical task as it can provide input for improving the operational system. Through such an evaluation, the strengths and weaknesses of the existing system can be identified, and actions can be taken to improve it. Efforts have been made to develop frameworks and best practices for the assessment and comparison of the performance of LASs. Amongst the most prominent are the ‘Land Governance Assessment Framework’ (LGAF) of the World Bank and the ‘Global Land Indicators’ proposed by the Global Land Tool Network (GLTN) and the United Nations Human Settlements Programme (UN-Habitat) in its Global Land Indicators Initiative (GLII). The GLII indicators are closely related to the UN-Sustainable Development Goals (SDGs) indicators on land tenure security, namely SDGs 1.4.2 (%adults with secure tenure rights), 5.a.1 (%agricultural population with secure rights over agricultural land), and 5.a.2 (women's equal rights to land ownership).

The Land Administration Domain Model (LADM), an International Standard (ISO, 2012), can be used to monitor global indicators proposed by various international organizations and to evaluate the performance of LADM-based LASs, as LADM Edition II now provides full support for all land administration (LA) functions including marine georegulation, valuation information and spatial plan information. Interface classes to the LADM are designed to support the generation and management of products and services, such as the monitoring of global performance indicators for LASs.

This paper is a follow-up on Chen et al. (2024), which was focusing on formalizing SDG land related indicator using LADM. The objective of this study is to explore the extent to which LADM can be used to also monitor the indicators of LGAF and GLII. To this end, the indicators are categorized according to their degree of association with LADM (i.e. full computational association, partial computational association, indirect association, association with other standards and non-association), and interface classes are created based on the results. The results show that LADM can be used to monitor a significant portion of the indicators of LGAF and GLII, although most of the indicators are related to a country's national legislation, its implementation and organizational decisions and capability.@en

The decision to refine the existing content and to extend the scope of Edition I of the ISO 19152:2012 Land Administration Domain Model (LADM) is a response to requests from the international Land Administration (LA) community. This response has to be formally organised in accordance with ISO guidelines. This begins with gathering feedback from ISO/TC 211 Member States on the need for updated and enhanced capabilities of the LADM. In addition, several proposals have been made to extend the scope of the LADM Edition I. After analysing the feedback received, it was proposed to develop the LADM Edition II as a multi-part standard: Part 1 — Generic conceptual model, Part 2 — Land registration, Part 3 — Marine georegulation, Part 4 — Valuation information, Part 5 — Spatial plan information and Part 6 — Implementation aspects. In other words, Edition I focuses on land tenure, while the design and development of Edition II is based on the inclusion of rights, restrictions and responsibilities (RRRs) concerning marine georegulation, valuation information, spatial plan information as well as LADM implementation. 3D representations are relevant for all parts.

This paper focuses on the design of the new structure of the second edition of the LADM and on the (operational) capabilities of this new edition in relation to the LA issues in Parts (standards addressing a specific part of the scope) and Packages (groups of conceptually close classes), with a particular attention to the requirements and design related decisions taken in the revision process. The parts 1, 2, 4 and 5 are the parts in which the authors are currently involved. Part 1 will be a high-level umbrella standard; Part 2 is largely based on LADM Edition I and focuses on land registration, with an enhanced support on the surveying functionality, including new subclasses of spatial unit, and extended 3D spatial profiles. Part 3 harmonises the description of RRRs and aligns land concepts with marine aspects from the marine domain based on the International Hydrographic Organisation (IHO) S121 Maritime Limits and Boundaries Product Specification. Part 4 deals with valuation information used and produced in the context of land administration, while Part 5 deals with spatial planning information and includes the planned use of the land (zoning), resulting in RRRs. Lastly, Part 6 is planned to be about implementation of the LADM and will be developed in close collaboration with the Open Geospatial Consortium (OGC).

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The importance of assigning value to unregistered land may play a crucial role for efficient land management, including acquisition, taxation, and transfer processes. This valuation could be central to establishing tenure security and recognizing legitimate land rights, impacting local and regional economics, governance strength, and the functionality of land markets. The New Urban Agenda highlights the need for competent valuation of unregistered land, which involves a transparent and accountable process, often hindered limited professional expertise, and overall data scarcity. Significant research and guidelines from various organizations, including FIG, FAO, GLTN, Namati, and RICS, have contributed to the understanding of the valuation of unregistered lands. These efforts have resulted in publications such as the Valuation of Unregistered Lands: A Policy Guide by UN-Habitat, providing practice-based guidance for valuation related to land-based financing, taxation, and fair compensation assessments. This guide together with the manual developed is universally applicable, offering a comprehensive framework for valuing unregistered land in various contexts and locations. It incorporates established best practices and protocols, detailing key valuation concepts, professional capacity-building, and includes practical tools for valuation professionals. As part of the ongoing revision of the ISO 19152 the Land Administration Domain Model (LADM), which includes a Part 4 focused on valuation, questions arise concerning the adaptability of the Social Tenure Domain Model (STDM) to address the valuation of unregistered land. This paper investigates whether STDM can be extended to accommodate the specific demands of the valuation of unregistered land and explores the necessary modifications required to develop such an extension that is both sophisticated and practically applicable in an informal setting. To effectively extend STDM for valuation purposes, it is crucial to incorporate specific valuation functions capable of capturing land values based on various criteria like location, land use, and potential for development. These functions must be adaptable to different economic conditions and real estate markets to ensure accuracy and relevance also in an informal setting. The model must also enhance its data integration capabilities to manage a range of data sources effectively, including market data, but also not formally recognised supporting documents. Considering the contexts in which STDM is typically used, the model should feature user-friendliness and not too complicated procedures that are intuitive and accessible for individuals without formal training. Simplifying both the input and output processes is crucial to ensure the model's usability and clarity. Furthermore, the model should be scalable to handle various sizes and types of buildings and plots and flexible enough to adapt to diverse local legal and economic environments. Further, and this is crucial to any standard development, interoperability must be ensured so that the data can also be included in any formal system used within the specific country. This paper describes the development of the STDM Valuation of Unregistered Land and how specific aspects and considerations were derived from literature and practical experiences to develop such an extension. With the development of the STDM Valuation of Unregistered Land the aim is to contribute to more equitable and effective land administration practices worldwide.@en

There is a need for high quality, reliable and up-to-date database management systems to determine sustainable property management policies in smart cities. The database management systems capable of storing 2D and 3D spatial information can be effectively used in smart city applications related to many data themes such as buildings, cadastre, transport, land use, etc., considering the needs of applications including property valuation. The property valuation process involves an impartial assessment of the various elements that influence the potential value of a property that is not only rights, restrictions, responsibilities (RRRs), condition of real estate, spatial planning status and constraints but also environmental, geographical, location and socio-cultural information. While traditional cadastral systems provide legal information about properties with 2D geometric information, 3D building and dwelling models can provide more meaningful data for GIS analysis that can be used to increase the accuracy of real estate valuations. If a country has an effective National Spatial Data Infrastructure (SDI) with 3D support, it can be used to link different data themes, such as buildings, cadastre, land use, addresses, etc., that are required in valuation processes. However, to meet today's 3D real estate valuation needs, an extension to NSDI may be required for property valuation registers. ISO/DIS 19152-4 Valuation information specifies the characteristics and semantics of valuation registers maintained by public authorities. It covers all administrative valuations and all input and output data within the valuation processes.

The purpose of this study is to extend the NSDI of Türkiye with ISO 19152-4 Valuation information and local value affecting factors to cover all the characteristics required in the 3D real estate valuation, and to implement the developed data model. The developed data model is tested using real 3D dwelling data, and data (value affecting factors) collected through a questionnaire. The scores of each 3D condominium unit are calculated based on the questionnaire answered by the valuation experts.@en

The boundary of real property is the fundamental element for securing rights attached to land. Countries, even with a long-standing cadastral tradition, often face the challenge of interpreting the course of a parcel boundary on the ground based on the available evidence, as data quality is very heterogeneous. Various cadastral principles and procedures have been developed for the determination of parcel boundaries in the field, which may also be associated with resolving boundary disputes. This article documents and compares the principles and procedures applied in the determination of property boundaries in selected civil law countries based on a novel conceptual model developed for that purpose. The notion of ‘boundary determination’ used in this article refers to demarcating and surveying land parcel boundaries during the initial cadastral survey and cadastral update procedures. The selected countries include Denmark and Sweden, which apply Nordic civil law; Slovenia and Turkey, which apply German civil law; and Spain, which applies Napoleonic civil law. The demarcation principles and processes applied in the different cadastral systems, the parties involved, and the evidence taken into consideration in these processes are described and compared. The main aim is to contribute to the documentation of the reasoning applied to the property boundary determination in the selected civil law countries.

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This paper examines the requirements based design of the LADM Edition II. The requirements are the starting point for the Abstract Test Suite (ATS, Annex A in an ISO standard). The requirements/ATS can be used to assess if a given LADM country profile with a specific application schema is conformant with the LADM standard. The requirements are a new aspect of ISO standards and this offers several benefits: 1. requirements express explicitly the needs from experts in the domain, 2. requirements are a very concise manner to describe the content of the standard, 3. requirements are used to introduce of the actual standard content (in the case of LADM, part of the UML class diagram), and as mentioned above, 4. requirements form the basis of the ATS. This paper describes the new structure of the second edition of the standard and the capabilities of this new edition, which is organized in multiple Parts (standards addressing a specific part of the scope) and Packages (groups of conceptually closely related classes, i.e. with relative high number of associations between the classes from one package compared to the number of cross package associations), with a particular attention to the requirements and design related decisions taken in the revision process.@en

In February 2019 the OGC White Paper on Land Administration is published. This White Paper provides an overview of the land administration domain and relevant developments. It also proposes necessary actions for the design and development of an implementation standards. The document includes an overview of needs and requirements as earlier discussed during the various LADM Workshops. During the closing session of the 2021 LADM/3D workshop (embedded in the FIG e-Working Week 2021) FIG expressed its commitment to collaborate with ISO and OGC regarding the implementation of LADM as an integral component of the standardisation efforts in land administration. Currently, the LADM revision is ongoing and includes land registration, marine space geo-regulation, valuation information, spatial plan information. Further, enhanced support in cadastral surveying is proposed to be provided, through a comprehensive survey model. The new edition is multipart, part 6 is on a standard for LADM implementation. The development of this can be strategically aligned with the developments of the other parts of LADM edition II. This paper serves as an initial step towards fostering a dialogue to promote the implementation of LADM. It emphasis the creation of a Land Administration Domain Model Standards Working Group Charter within the OGC. A draft charter is currently available for reference, along with insights from the 2019 White Paper. It is imperative to engage stakeholders from industry/business, government and academia in this development to ensure its success and relevance.@en

The first edition of the Land Administration Domain Model (LADM) has been available as a formal International Standard since the 1st of December 2012, published as ISO 19152:2012. It is based on / makes use of a number of standards, in particular those published by ISO/TC 211 and, of course, other committees. In addition, non-ISO standards and international guidelines related to land administration have been used as much as possible in the development of LADM Edition I. The systematic review of LADM Edition I has been officially launched and the process of developing LADM Edition II is now underway. The new edition not only refines the content of LADM Edition I, but also expands the scope to include marine georegulation, valuation information, spatial plan information and implementation. As a result, LADM Edition II is based on more standards, not only because of its expanded scope, but also because of the standards published after LADM Edition I and the principle of reusing existing standards wherever possible. Since the publication of LADM Edition I, it has been widely recognised by the international community and implemented by several countries. It is also applicable to the implementation of relevant parts of international standards, guidelines and frameworks, as well as the Sustainable Development Goals (SDGs). LADM Edition II has somewhat more links to international standards, guidelines and frameworks, as its scope is broader than Edition I. The purpose of this paper is to document which standards LADM Edition II is based on and associated with, which guidelines and frameworks are in some way related to LADM.@en

The timely and effective dissemination of property values is an essential part of a transparent and efficient property valuation system. Over the last decade, web-based data-sharing systems have been increasingly used for the dissemination of assessed property values. 3D valuation units (e.g., condominium) and groups (aggregation of valuation units, e.g., a building floor in a multi-occupied building, a multi-occupied building, street, district or valuation zone) may be required to better communicate with users and to support a more effective and efficient dissemination. However, none of these systems share valuation information associated with 3D representation of the valuation units and groups. In this paper, a prototype of a web-based system is developed utilising the proposed Valuation Information part of the Edition II of the ISO 19152 Land Administration Domain Model compliant dataset for not only disseminating the spatial, physical, thematic and temporal characteristics of 3D valuation units, but also for sharing the valuation statistics at each designated level and with level-specific attributes. It is expected that the outcomes of this work may contribute to the development of local or national valuation systems and systems for geo-based data visualisation for effective and efficient sharing of valuation information. As such, it is anticipated that the study's outcomes will not only increase the level of communication with the public, but also support politicians and planners in their decision-making processes and help them to better analyse and understand the property market. With the proposed system, confidence in valuation results can be further increased due to the high level of transparency.

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Among the topics that are introduced and/ or being refined in the context of the revision of the LADM 19152:2012, the legal Land Administration-related aspects are being investigated. With the knowledge and the experience from the developments of the LADM so far, and the ongoing discussion between the parties involved in the standardisation process, the need to clarify certain legal land-related aspects and to examine the alternatives for further refinement is highlighted. Therefore, this paper presents prior work on LADM-related legal aspects since the vote of LADM as ISO standard (2012), till the time of the preparation of this paper (2021) to report the necessary background for this research. This concerns the developments related to the various legal refinements that have been proposed during this time period and specifically the refinement of the legal profiles, the LADM functional support to representation of both statutory and customary tenure and the work regarding the explicit definition of restrictions that arise from Public Law. Moreover, this paper focuses on documenting the proposals on a refined legal model for the LADM Edition II. These include the following: (a) more detailed classification of RRRs, based on the two major types of interests in land: privately agreed interests as well as regulations imposed by a public agency and Public Law restrictions. The paper also includes (b) a discussion on the extent that LADM Edition I provides efficient support for the title and deed registration systems (as others e.g. in socialist environment), as well as (c) a discussion on how restrictions and responsibilities can be modelled as rights’ relationships between an owning and a benefitting Party. @en

The interest in using 3D data in property valuation has been increasing during the last decade. The usage of 3D data models in valuation can be basically grouped in two main categories: (a) supporting mathematical models with variables produced through 3D analyses (e.g. view) in order to better estimate the values of properties and (b) consuming 3D data models to visualise valuation units in 3D and disseminate values of properties associated with the visualised units (legal or physical space). The current paper focuses on the latter category in particular. The main purpose of this paper is to develop a prototype system utilising the proposed Valuation Information Model extension of ISO 19152 Land Administration Domain Model (LADM_VM) compliant dataset in order to create web-based, thematic valuation maps for 3D valuation units (e.g. condominium) and groups (e.g. multi-occupied building). In the first part of the paper, it is attempted to justify why an extension to the core LADM is required to represent valuation information. It is noted that LADM_VM enables to record 3D spaces of valuation units, and input and output data of 3D analyses. Therefore, LADM_VM can be used as basis for developing 3D visualisation and dissemination prototype. In the second part of the paper, special attention will be given to the 3D visualisation and dissemination of spatial, thematic and temporal characteristics of valuation information and a prototype is developed using the open datasets of the Netherlands. It is expected that the outputs of this paper will contribute to the development of local or national prototype systems for sharing valuation information effectively and efficiently. Therefore, it may be considered that the outputs of the paper not supports in increasing the communication level with public, but also supports politicians and planners in decision-making processes and helping them to understand the property market better. With the proposed system (prototype) the trust in the valuation is expected to further increase due to the high level of transparency. @en

Τhe built environment has a vast and ever-growing number of complex and multi-layered buildings and other structures. The number of those is growing because of the increasing pressure on the limited space in cities. It is important to note that different professional sectors are involved in the realization of a new building. These sectors are mainly the Architecture, Engineering, Construction, and Owner Operator (AECOO), and land administration, which covers the cadastral registration, spatial or zoning plans, as well as property valuation. Noteworthy to mention at this point is, that today the subdivision plans regarding apartment rights in buildings are to be provided on the floor plans as submitted with the building/construction permit request. These plans show the apartment boundaries as twodimensional (2D) representations, which are insufficient to clearly and completely describe the ownership rights in multi-storey buildings. What is more, the building parts obtained from 2D representations are also inadequate to estimate the valuation of these apartments in both taxation and selling/buying processes. Considering that digitalization and consequently digital data are becoming more and more the norm in the AECOO industry, including the building permit requests, there is an opportunity to exploit Building Information Model (BIM), specifically Industry Foundation Classes (IFC), in the registration of apartment rights in three-dimensional (3D) representations. To investigate the opportunity, this study will further analyze the cases of the Netherlands, Saudi Arabia, and Turkey by revealing the similarities and discrepancies with respect to the registration of apartment rights in terms of legislative basis and current practice and extrapolating the current 2D practices into fully 3D representations. In earlier work, ISO19152 LADM-based models for the 3D building legal spaces have been developed and are related to BIM/IFC. The main objective of the study is to highlight the possibility of providing an internationally standardized modeling specification for 3D registration of legal rights within buildings, based on the earlier detected information model overlaps. What is more, it is expected to increase the awareness in other sectors than land administration with regards to legal spaces in the buildings. Finally, this study endeavors to provide concrete guidelines for the other sectors, most specifically the Architects, regarding the type of information that BIM/IFC models should have, in order to facilitate the 3D registration of apartment rights. @en

A code list in Unified Modeling Language (UML), a simple list of values without any structure, can be employed as a simple data type to further capture the semantics of a domain. The code list values as used in international standards (e.g. ISO and OGC) are generally presented without definition, reference to the source of a definition, multi-lingual alternative term support and semantic relationships (e.g. hierarchical, associative). Moreover, managing, implementing, and maintaining UML code lists can be considered as a difficult task since they generally do not provide structured and semantically enriched values. This is also true in the case of ISO 19152:2012 Land Administration Domain Model (LADM), which is currently under systematic review and adding more content, meaning and structure to code list values could be considered an improvement. In last decade, there is a growing interest in representing terms as well as code list values using Semantic Web technologies (e.g. RDF, OWL, SKOS, SPARQL) and making them available on a registry (e.g. ISO/TC211 Geolexica, OGC Definitions Server, INSPIRE code list register, BARTOC), including land administration domain (e.g. CaLAThe, LandVoc). However, there is no joint understanding in structuring, extending and maintaining code list values, which may be achieved through an agreed metamodel. Such a metamodel should also provide insight into content, localisation (multi-lingual support), versioning and implementation. The aim of this study is to propose a framework (basically a metamodel) for structuring, extending, maintaining and implementing semantically enriched code lists, and to discuss the application of the proposed framework to be included in the revision of LADM. To achieve this aim, the requirements for refined code list values are firstly collected considering existing thesauri, vocabularies and standards. Subsequently, a metamodel is proposed for the refined code list. The proposed metamodel is applied to a code list of LADM as well as a part of a selected country profile.@en

Spatial data in a Land Administration (LA) establish a fundamental geospatial data theme (see UN GGIM, 2018) and the integrated geospatial information framework for any Spatial Data Infrastructure (SDI). Domain-specific standards, an integral component of the SDI, play an essential role to represent the semantics of domains, specify links between distributed registries and databases, and stimulate the development and implementation for Land Administration Systems (LAS). As an international descriptive standard providing an abstract conceptual schema, the ISO 19152:2012 Land Administration Domain Model (LADM) has been used and is being used as a reference for the implementation of LAS. Various approaches have been used for the LADM implementation that includes elaborating (via a country profile) and realizing a technical model suitable for the implementation (van Oosterom and Lemmen, 2015). LADM focuses on a specific function of LA that is interested in Rights, Responsibilities and Restrictions (RRR) affecting land, and the geometrical components thereof. The land value function of LA is considered outside the scope in the first edition. Recently, for extending the flexible and modular basis of the LADM, a valuation information model is developed for the specification of valuation information maintained by public authorities. It identifies the links between property valuation and the other LA registries and databases (e.g., cadastre, land registry, building and dwelling registries) that may enable interoperability across systems. The conceptual schema of the model provides a common basis to direct the development of local and national valuation databases and information technology products and services, following an approach similar to the LADM implementation. The proposed LADM Valuation Information Model is on the agenda of the development of the second edition of LADM within ISO/TC211. The operability of the newly proposed conceptual model needs to be evaluated through technical implementation. This paper describes the development of a prototype for the implementation of the LADM Valuation Information Model and assesses its operability through a case study for Turkey. The primary aim of the paper is to test the capabilities of the LADM Valuation Information Model using the required and produced data in recurrent valuation processes, but not to build a specific information management system for Turkey. As the implementation of a LADM compliant prototype initially requires the development of a country profile at conceptual level, methodologies applied for LADM profile development are examined and then a Turkish LADM Valuation Information Model country profile is proposed using the Conceptual Schema Languages (CSL) of the Unified Modelling Language (UML) and INTERLIS. INTERLIS is a formal language as well as a set of software tools that support LADM implementations. Subsequently, approaches and tools used in the LADM implementation are investigated and utilized for the automated transformations from the country profile to several technical models. In this context, the article presents the experiences gained during the implementations. Moreover, strategies for implementing and managing property valuation information more efficiently (e.g. bi-temporal aspects of valuation information management) are also studied and applied to the implementation. The generated technical models are then populated with sample datasets related to recurrent property valuation including the geometries of valuation units, as well as valuation information covering several years. The developed prototype is then tested through a number of queries to assess whether the LADM Valuation Information Model fulfils information management needs of recurrent valuations. The main contribution of this paper is to provide a holistic approach on how to develop an LADM conformant prototype for managing property valuation information.

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The timely and effective dissemination of property values is an essential part of a transparent and efficient property valuation system as property values are required in several land administration processes, such as land acquisition, taxation, transaction, consolidation, readjustment and transformation. In the last decade, a web-based data-sharing system has been increasingly used for dissemination of property values. The 3D visualization of valuation units may be required in order to better communicate with users and provide more effective and efficient dissemination, however, none of those systems share valuation information associated with 3D representation (legal or physical) of property (valuation) units. The objective of this paper is to reveal the requirements, opportunities and challenges for web-based 3D visualization and dissemination of property valuation information. To deliver this objective, the requirements for U(ser), D(ata), and V(isualization) are investigated. The general public/property owners and professionals are determined as main user groups in this research. For each of the groups specific data and 3D visualization requirements are discussed and a number of suggestions are provided for developing an effective dissemination of property valuation information. These requirements includes the visualization of multi-part properties (e.g. condominium unit, storage unit, car parking), thematic mapping of valuation information, and aggregation of valuation units into valuation units groups. Furthermore, the capabilities of the LADM Valuation Information Model as a schema for storage, and the features and functionalities of 3D visualization platforms (geoweb viewers) in terms of better value dissemination (e.g. altering visual variables, solution for occlusion, visualizing below surface properties) are briefly investigated. Lastly, an initial prototype is developed and presented.@en

A new edition of the Land Administration Domain Model (LADM) is under further development in ISO/TC 211 on Geographic Information. The Committee is developing this new edition of the LADM – as multipart – working titles are as follows: Part 1 – Fundamentals Part 2 – Land Registration Part 3 – Marine Space Georegulation Part 4 – Valuation Information Part 5 – Spatial Plan Information Part 6 – Implementations The decision to publish LADM Edition II as multipart had as a consequence that a New Work Item Proposal (NWIP) and a Working Draft (WD) have to be formulated for each Part. In 2020, the NWIP/WD have been submitted to ISO/TC 211 for Part 1 by Standards Australia (SA) with input from the author team on behalf of the FIG. The result of the voting was positive. Comments have been submitted, which will be processed and used in the next stage of the standard: the Committee Draft. It is planned that FIG will submit the NWIP for Part 2 before summer 2021. And it is expected that the same will happen this year for Parts 4 and 5. Those submissions are expected to be in close cooperation with other international professional organisations (i.e. IHO, RICS, OGC, etc.).@en

Condominium is a special and relatively new type of property right emerged in the last century to be a remedy for the management problems in multi-unit buildings. There are many types of condominium regimes, as described in EUI (2005), UNECE (2005) and van der Merwe (2016). The common elements include: (a) Individual right to an apartment, (b) co-ownership (joint ownership) of the common property or the whole property, and (c) membership of an incorporated or unincorporated owners' association (van der Merwe, 2015, p. 5). The ownership shares in the common property are here referred to as co-ownership shares; yet, alternative terms include ownership fraction, condominium share, participation quota, share value, and unit entitlement. Generally, these shares will determine the proportional contribution to the common expenses and the share of common profits, as well as the voting power of each condominium unit owner in the administration of the condominium. The most common approaches to the determination of the co-ownership shares are based on equality, relative size or relative value of each condominium unit, or a combination of such (van der Merwe, 1994, p. 57–58). The literature presents detailed descriptions and comparative analysis related to condominium systems in different jurisdictions (e.g. van der Merwe, 2015; 2016; Paulsson, 2007; EUI, 2005; UNECE, 2005); however, the procedural aspects related to the allotment of co-ownership shares still need to be further investigated. This article aims to describe condominium systems in the Netherlands, Sweden and Turkey, and compare legal provisions and procedures related to the allotment of co-ownership shares in these jurisdictions. The main purpose is to clarify the methodologies behind the determination of the co-ownership shares in national systems to bring new insights to countries, which are trying to revise their national provisions.

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