The qilin ransomware group listed Tohlen Building Technology Group on its data leak site on 2024-05-03. Country: DE Sector: Professional Services Claim as published on the leak site: We are a medium-sized building technology company and currently employ around 140 people. These are increasingly active in the Aachen, Cologne, Bonn, Düsseldorf, Duisburg and Essen areas. Of course, also beyond these limits.