Industry giant Sika of Switzerland is one of the suspected companies. Sika's shares fell 3.1 percent to their lowest level in several months after the announcement.
Companies such as Chryso, Mapei, Master Builders Solutions, MC-Bauchemie Müller, TAM, Liesen and Remei are also suspected of being involved in the cartel.
The companies risk fines of 10 percent of annual revenue if the investigation shows that they are guilty of price collusion.
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