Thyssenkrupp's non-executive board will be led by a labour representative until a permanent successor is found for outgoing Chairman Ulrich Lehner, the German technology group said on Tuesday.
Lehner recently announced he would quit the conglomerate at the end of July. His departure came only days after chief executive Heinrich Hiesinger resigned amid calls by activist investors Cevian and Elliott to deepen restructuring efforts.
Markus Grolms of trade union IG Metall, who currently serves as Thyssen's deputy chairman, will head the supervisory board from Wednesday for the time being, a company spokesman said.
German corporate rules require half of the directors of a German listed company's non-executive supervisory board - including the deputy chairman - to be labour representatives.