ZURICH (Reuters) - Activist investors seeking to block specialty chemical maker Clariant's $20 billion merger with Huntsman Corp have boosted their stake in the Swiss group above 20 percent, triggering an official disclosure filing, a source familiar with the matter said.
The White Tale consortium has repeatedly declined to respond to Reuters enquiries about its plans. The activists had told a Swiss newspaper this month they had "significantly more" than 15 percent of Clariant shares and wanted to increase their stake.