An investigation conducted by Monitor magazine found that the industrial Knauf group and WKB Systems provided materials for reconstruction of Mariupol that had been almost entirely destroyed during the first months of the Russian full-scale invasion of Ukraine.

The authors of the investigation analysed images from construction sites and found materials with Knauf's logo, while WKB Systems was claimed to be one of the main contractors in Mariupol.

Business & Human Rights Resource Centre invited both companies to respond. Knauf provided a response which can be found below. WKB Systems did not.