China Cosco Shipping raising its stake in the stock-listed Port of Qingdao has opened up new revelations about the state-controlled companies that make up the shipping sector of China Inc.

New disclosures show that by 2019, the state shipowner could be spending almost $100m per year on port services at Qingdao alone, where it sits on both sides of the table, having recently raised a previous 2% shareholding to 20%.