Friends on the Invoice

Public procurement represents an important instrument of financial management for the state and local governments. Given the volume of funds distributed through these processes, it is crucial to ensure their maximum transparency and efficiency. In practice, however, complex schemes often appear, involving intricate networks of individuals and companies. This applies not only to the public sector but also to large corporations with extensive networks of subcontractors. One of the consequences of such non-transparent and complex relationships may be the distortion of fair competition, inflated contract prices, or the risk of conflicts of interest. In some cases, subcontracting structures are deliberately designed to conceal the actual recipients of invoiced payments or to obscure influence over decision-making processes. The motivation of this thesis is to contribute to solving this problem by developing an approach that enables the systematic identification and analysis of suspicious relationships between entities. The proposed tool can serve both the public administration, for example for audit or control purposes and the private sector, where it may support internal due diligence, risk management, or compliance processes.