New Delhi, June 21 -- The ministry of corporate affairs has begun a crackdown on companies that failed to file their geo-tag details by the middle of this month. It had asked every company to file information, including photographs of its office, directors and key officials, to help identify shell companies that exist only on paper for such dubious purposes as money laundering. After demonetization, dummy firms came into handy for people to shunt black money around. There are also suspicions that terrorists could use them to route funds. The scale of the problem is evident from the fact that only about 60% of the nearly 1.9 million companies registered in India on 1 April were active. Why do the rest even exist?...