MUMBAI: Lanco Infratech , the power and roads builder, became the first company to face bankruptcy proceedings among the dozen identified by the regulator as IDBI Bank has decided to recover its dues by taking the resolution to insolvency courts, said a person familiar with the matter.The bank has fund based exposure of Rs 7,799 crore and non-fund based exposure of Rs 3,349 crore as on March 2016, while the overall dues from the company are more than Rs 17,000 crore even as the company's market capitalisation is just a fraction of it.Lanco Infratech, Amtek Auto Alok Industries and Bhushan Steel , which were trading like penny stocks, tumbled further as investors are factoring in no equity value in the dozen companies identified by the Reserve Bank of India to be taken to bankruptcy courts.Power and road producer Lanco Infra tumbled to limit, or 20 per cent, and Amtek Auto which is not in the current list but is hanging precariously, also crashed 20 per cent to Rs 1.80 and Rs 23.45, respectively, a share as investors fret that after reorganising debt and new equity investments, the current value of shares may be nothing.Banks led by IDBI Bank has initiated insolvency proceeding against Lanco Infratech, the first among the 12 stressed accounts that were identified by the RBI after they were empowered to direct banks to take action against defaulting borrowers.The company controlled by a former Congress party Parliamentarian owes banks Rs 18,000 crore and its market value is at Rs 613 crore. Alok which owes Rs 13,000 crore is valued at Rs 325 crore and its promoter holdings has fallen to 29 per cent from 33 per cent two quarters ago, BSE filings show."For the next six months, lenders and the promoters will be on their toes to arrive at an amicable resolution," said a bank official from SBI who did not want to be named."The joint lenders forum will be meeting regularly to arrive at consensus among lenders before approaching the NCLT," he added.Investors who have been trading in these stocks for years hoping that there could be a restructuring of loans and existing shareholders would benefit are losing hope.With the RBI mandating bankruptcy proceedings, many believe that new set of investors would have to invest equity and existing ones will be wiped out even if promoters managed to hang on by bringing in more funds.Meanwhile, shares of Jyoti Structures, which is one of the 12 accounts identified by RBI, hit the upper circuit as it rose 20 per cent to Rs 11.76 a share. Among others, Alok Industries was down 10 per cent while Monnet Ispat was down 13 per cent.