The stock tumbled 43 per cent to Rs 50.70 -- its 52-week low -- at the BSE.
On NSE, it plummeted 39.98 per cent to Rs 53.50.
In the previous session, the stock crashed almost 31 per cent.
".... Contracts for new expiry months for Amtek Auto shall not be available for trading in equity derivatives segment on expiry of existing contract months," the BSE said in a notice yesterday.
However, the existing unexpired contracts of expiry months August, September and October 2015, would continue to be available for trading till their respective expiry and new strikes would also be introduced in the existing contract months, it said.