An article from Reuters reports on how China is attempting to wrest pricing power away from iron ore miners:

China will refuse to grant new licences to iron ore importers unless they participate in a domestic trading platform, in a fresh move by the world’s biggest iron ore consumer to wrestle pricing power away from global miners. … Under new rules, traders and steel mills seeking a new licence to import will now have to trade at least 500,000 tonnes of iron ore on the platform set up by the China Beijing International Mining Exchange (CBMX), a document on the regulations showed. Only Chinese firms are eligible for import licences.

More details at the article: China seeks to lock iron ore importers into trading platform