Glencore takes a £4bn hit
It relates to business in Nigeria, the Democratic Republic of Congo and Venezuela from 2007.
Glencore runs huge copper and cobalt mines in Congo, and trades in Nigeria and Venezuela.
It has more than a quarter of the world’s cobalt output, most of it from Congo.
Glencore, run by billionaire Ivan Glasenberg, was founded in 1974. With its headquarters in Baar, Switzerland, it operates in 50 countries.