Confirmation that Trafigura has secured $4bn of new credit facilities while clearly scouting for shipping tonnage puts the spotlight onto an increasingly important micro-sector.

The rise and rise of the privately held but mega-scale commodity traders, which also include Cargill, Vitol and previously Glencore — now public — has been an astonishing phenomenon of the last 10 years.

The fact that businesses have to disclose very little about their affairs makes it hard to assess with pinpoint accuracy their exact scale, ambition or impact, but it also partly explains their success.

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