Usha Martin has received shareholder approval to issue 3.428 crore warrants (at a maximum price of ₹35 a warrant) to its promoters, promoter group and their relatives and associates on preferential basis, the company informed the exchanges on Wednesday. Shareholders have also approved ₹400-crore non-convertible debentures issue on private placement. The NCDs will be issued to individuals or institutional investors including FIIs, venture capital funds and insurance firms.