UPDATE 1-Activist investor ups stake in Thyssen, boosting shares
September 25, 2013 at 03:53 AM EDT
FRANKFURT, Sept 25 (Reuters) - Activist investor Cevian has raised its stake in ThyssenKrupp to 5.2 percent and said it could buy more, in a move that was welcomed by the German steelmaker's CEO who is struggling to push the firm into new higher-margin businesses.