Indian Energy Exchange (IEX) stock hit a two-year low of Rs 116 on BSE due to downgrades by brokerages after the power ministry announced the introduction of a market coupling method for spot power trading. The market coupling may damage IEX's "moat" and allow other exchanges to cut into its market share over time, leading to volume growth threat. Nuvama and Antique Stock Broking downgraded the stock to sell.