Art trade during the Nazi era was characterized by secrecy, corruption, violence and injustice. The Nazis took advantage of the art market as it proved to be a convenient source of income to finance military operations. Modern works were demonized and destroyed with the aim of creating authentic German art, but those with commercial potential were used. The Nazis collected the valuables that the exiled Jews left behind in order to resell them through market centers in Switzerland, Paris and London. The functioning of the art trade during the Nazi era has been intensively researched by authors Jonathan Petropoulos, Meike Hoffmann, Lynn H. Nicholas and Catherine Hickley. Art dealers played a key role for the Nazis. Thanks to their international contacts, they sold the stolen art all over Europe. Considering the huge number of participants in this carefully coordinated robbery, Hildebrand Gurlitt, Bruno Lohse and Karl Haberstock are singled out in this paper. They were chosen because of the great popularity they had on the market and among the Nazis. The data on their movements and actions are therefore extremely valuable for understanding the art trade under the Nazis. The specificity of H. Gurlitt, B. Lohse and K. Haberstock is also in the prominent status they had within the hierarchy and the large amount of available biographical data. The subject will be approached with a biographical comparative method where the role and functioning of an individual dealer will come to the fore. Each had their own network connection in which there are many intersections indicating their distinct connection. The goal is to present the structure of the art trade during the Nazi era through the work of H. Gurlitt, B. Lohse and K. Haberstock, and to highlight some aspects of this issue that continue even in modern times. The art market, for example, was shrouded in secrecy, which greatly improved the efficiency of illegal transactions. In the modern age, privacy is still an essential principle of auction houses, although it complicates cases of restitution. Today's approaches to restitution are more meaningful. Thanks to open information systems, it is known that the responsibility of the Nazi dealers is greater than what was initially assumed after the Second World War.