## 1 Introduction
These tools enable investigators to sift through financial data efficiently and identify patterns indicative of asset concealment. In this context, the fundamental challenge is to enable a consistent integration of the data associated with this type of fraud to enhance the use of related investigative tools and techniques. This is because data are commonly dispersed across various databases, from different departments, employing different models, and often stored in diverse formats [3]. Removing these data silos through internal data integration remains a significant challenge. The data integration problem becomes even more complex due to the transnational nature of this type of fraud, as fraudsters often conceal assets beyond the borders of their home country. If integrating data within a single organization or between organizations in the same country is already complex, achieving effective integration across national borders introduces even greater complexity. To address the aforementioned issues, this paper proposes the construction of an ontology designed to map and organize the body of knowledge related to asset concealment since, to the best of our knowledge, no public ontologies in this area were found. Ontologies are essential in data integration because they enable a common understanding of the data across various systems and domains by establishing a shared vocabulary and set of concepts. This ensures that data related to asset concealment investigations from disparate sources can be effectively integrated, queried, and analyzed. During the ontology construction, an extensive survey of data related to asset concealment across different countries was conducted to develop an integration model with a cross-organizational and transnational scope. The concepts and relationships mappedduring this work embody the knowledge acquired from experts and detail the entities and processes used by fraudsters to conceal assets. Beyond aiding in data integration, this ontology can potentially assist governments and organizations with limited expertise in better understanding this complex field of knowledge. Various ontology construction processes were analyzed to support the build of the proposed ontology. In all the processes analyzed, a gap was identified in essential aspects of ontology construction in complex domains, such as the need for transnational integration among different entities. Within these points, issues such as the absence of activities that enable the partial reuse of concepts from related ontologies or the incorporation of knowledge and data relevant to the problem but originating from outside the boundaries of the organization, which is modeling the ontology, stand out. For this reason, and to address these gaps, this work also proposes a process for domain ontology construction. The proposed process enables the incorporation of different elements in an ontology that extend an organization's internal concepts at a global level. Moreover, an additional step of the proposed process includes integrating existing up-level and domain ontologies with the newly proposed ontology. It addresses the gap presented by introducing a technique known as reference ontology alignment, which provides a structured approach to integrating and harmonizing ontologies. The main contributions of this paper are as follows:  
* Construction of an ontology to support the data integration in the domain of asset concealment fraud and map flows and entities related to this fraudulent activity. * Validation of the transnational nature of the concepts and relationships mapped in the ontology through an extensive survey of existing data from some major countries. * Validation of the ontology through its instantiation with a sample of real, restricted-access data from multiple data sources of different Brazilian government agencies. * Proposal of a new ontology construction process emphasizing the partial alignment of related ontologies and a comprehensive method for defining concepts and relationships.