New Delhi: State-owned Coal India Limited on Friday announced the commencement of fourth tranche of auction for coal linkages for non-regulated sectors, including sponge iron and cement. “Coal India Limited (CIL) is commencing the tranche IV of auction of coal linkages for non-regulated sector,” the company said in a filing to BSE. CIL accounts for over 80% of domestic coal production. The Cabinet Committee on Economic Affairs had earlier approved allocation of coal linkages for non-regulated sector only through auction. PTI